# Thread: New VS Old Geometry

1. I have always done my own maintenance and always think it's a little weird when people take their bike to the shop for simple little things.

2. Originally Posted by smilinsteve
Picture your bike as a see saw, with your center of gravity sitting on top of it. Your bike takes hits from below, from the front or rear tire contact patch. If your center of gravity is roughly in the center of the bike, the bike will rotate around your COG more, and lift you less. If your weight is directly over the rear axle, force from the ground is directly lifting you rather than rotating the bike around you.

That's why in theory, super short chainstays will make you feel the hits to the rear wheel more, will lift you more, and will therefore be less stable.
Any hit you take while seated that's enough to noticeably lift you up is a mistake, because you're seated when you should know you shouldn't be, and an inch difference over 40-something inches in wheelbase isn't going to move the pivot point drastically enough to make a huge difference. Besides, the slacker head angle makes any theoretical pitch forward far, far, less dramatic. Short chainstays make the bike more maneuverable, that's why they've gotten shorter.

Originally Posted by smilinsteve
That's just theory of course. Lots of downhill bikes have short chainstays, but they normally aren't as short as they could be.
Ultimately, chainstay length in FS bikes is limited by packaging limitations, as in having room for the wheel to go as the suspension moves. But in practice, chainstay lengths were too long, because like HTA, people thought you needed road bike -like measurements to go fast.

Originally Posted by smilinsteve
From my experience, long slack bikes do NOT handle tight switchbacks as well as shorter, steeper geometry.
Unless you're talking about DH bikes, that's just not true. Like I said, the difference between absolute minimum turn diameter would be a couple of inches, at best. Anything that requires such a tight turning radius (that isn't in a parking lot) would be a chancy proposition regardless of what bike you're on.

I haven't come up on anything on my 6" bike that I can't maneuver around, and you don't hear about anyone who has. Yes, theoretically, it's possible...but realistically, it doesn't happen. Even if it did, those situations are so rare that the advantages of slacker, longer, geometry far outweigh any possible negatives.

This isn't some great conspiracy, trends change because the old ones weren't working as well as they could have been.

Why are all old vs. new arguments the same? Nobody is saying you can't ride your old bike, and if new bikes didn't get better through the passage of time (like everything else) people would be pretty pissed off.

3. Originally Posted by smilinsteve
Almost anything I do on my new bike I could do on any of my previous bikes. Put dropper posts on 90's bikes and that would really close the gap!

If a bike is steeper and more endo prone, you ride steep rocky downhills differently. That doesn't make it bad. It could make it extra exciting, actually. If you race or care about going as fast as possible, this stuff matters more I guess.

Riders get on the bike and figure out how to make it work. Equipment nerds get on the bike and ride down while thinking about the new parts or new bike they need so they can be more agro.

It's not the bike that excels at downhills, inspires confidence or "allows you" to clean more gnar, its the rider that makes it happen.
Not true, at all. I got on a slightly newer, slightly more long and slack bike at Interbike, on my local trails, and immediately set PR's. The geometry inspires confidence, which allows you to ride better. Mountain bike technology is ALL about making it easier and instilling confidence. Suspension, disk brakes, geometry, wheels size, all of it.

If you just want to tip-toe around the trails and make it as difficult as possible, go grab a vintage Stumpy, throw some skinnier tires on it, and make it a single speed. Strangely enough, people don't want to do that.

4. Originally Posted by goodmojo
Doesnt have to be. My friend rides about 5 days a week, maybe 80-100 miles/week mtb, won cat 2 last year. He does very little of his own maint, doesnt know anything about slack/steep, chainstays etc. He also only switches bikes every 5 years where most in his group switch every 2 years.

He knows that most of the gain is from riding. He doesnt really train, doesnt measure heart rates or anything like that.

He rides and wants to spend all his time riding, not reading forums, not debating tech etc.

I think it is a good way to be.
I think its a good way to be too.

5. Originally Posted by richde
Like I said, the difference between absolute minimum turn diameter would be a couple of inches, at best. Anything that requires such a tight turning radius (that isn't in a parking lot) would be a chancy proposition regardless of what bike you're on.
Curious, if you are climbing a trail with lots of chunk, would a steeper bike allow you to move slower and thus make it easier to maneuver around obstacles to find a good line? Do you have to maintain a bit more speed as the head angle slackens. Thanks

6. Originally Posted by Travis Bickle
I have always done my own maintenance and always think it's a little weird when people take their bike to the shop for simple little things.
I think so too. You can't be a true equipment nerd if you don't also like to fiddle around with adjusting and rebuilding your stuff.
My brother is the opposite of me. Every time I ride with him, I find his bike is shifting like crap, his rotors are rubbing, his fork is packing up, etc. Drives me nuts!

7. Originally Posted by richde
i've climbed about 100,000ft so far this year on my almost 30lb 6" bike. Htfu.
6"? Htfu

8. Originally Posted by bob_m
Curious, if you are climbing a trail with lots of chunk, would a steeper bike allow you to move slower and thus make it easier to maneuver around obstacles to find a good line? Do you have to maintain a bit more speed as the head angle slackens. Thanks
IME, no. One of my favourite bikes is my old 98 Explosif. That thing could climb and so can my Warden. The Warden is a better tech climber because of the suspension, but they are both maneuverable. Explosif is now my SS Townie bike.

9. Originally Posted by Travis Bickle
I have always done my own maintenance and always think it's a little weird when people take their bike to the shop for simple little things.
I'm guilty of this when I want to commute to work on my bike, but I don't have time to research how to do maintenance that I'm not familiar with. Then when I pick it up I'll ask questions as to how they did it.

10. Originally Posted by evasive
You're imagining this. Firstly, XC bikes aren't seeing any longer travel. Second, I know plenty of modern AM bikes built below 30 lbs.
That's not what I'm saying. People are doing XC type riding on non XC bikes. XC bikes are not that common anymore. I don't even think Santa Cruz, for instance, makes an XC bike. An AM bike that weighs under 30 lbs probably has a carbon frame and costs \$5000+

11. Originally Posted by richde
A short rear end doesn't make a bike unstable, that's a function of HTA and wheelbase
There's no way for this making sense - having less rear chainstay means less the ability to place weight before, past, and above the rear wheel. So, such the design can be found unstable. Not everyone rides seated.
Originally Posted by richde
...and what's more stable?
Riding style will dictate how stability is maintained.
Originally Posted by richde
A slacker HTA, and when you ride it right, it turns just as well, probably better than a steeper bike.
Again, this makes no sense. Taken to the extremes of steering input and feedback, each has their own rewards.

Alot of designs from the past 5 years would be better having more Reach w/o the standover height increased. That's about it.

12. Originally Posted by smilinsteve
Almost anything I do on my new bike I could do on any of my previous bikes. Put dropper posts on 90's bikes and that would really close the gap!

If a bike is steeper and more endo prone, you ride steep rocky downhills differently. That doesn't make it bad. It could make it extra exciting, actually. If you race or care about going as fast as possible, this stuff matters more I guess.

Riders get on the bike and figure out how to make it work. Equipment nerds get on the bike and ride down while thinking about the new parts or new bike they need so they can be more agro.

It's not the bike that excels at downhills, inspires confidence or "allows you" to clean more gnar, its the rider that makes it happen.

When I ride my older bikes I think of them as being different, not worse. It's a different kind of fun.
Super true. You can't be thinking about equipment changes while on a ride. That part of your brain needs to be turned off, to fully hear the mind that likes to crush.

I have been messing with the cockpit height and length on my new gravel bike almost every couple rides. There is a form to be found in almost every position. Can't think about changes, gotta be on the bike your on.

13. Originally Posted by richde
If you just want to tip-toe around the trails and make it as difficult as possible, go grab a vintage Stumpy, throw some skinnier tires on it, and make it a single speed.
Vintage stumpy's are awesome! 68 hta, fun in the sun. F the skinny tires and ss though, I'll take the original 15 speed friction shift and official Stumpjumper tires please.

14. Originally Posted by smilinsteve
What I'm saying is that I could ride my same trails on any of my old bikes and have just as much fun on any of them. I'm not saying the rides would be the same or take the same time.
You are so full of it. We all know you crashed and nearly died that one time you tried to ride NORBA geo on a trail. How could you not? We've all almost died because of those stupid steep HTA short top tube death machines, the dumber of us over and over again. And everyone knows, if they had shaved a half inch off those gargantuan chain stays, massive air and endless manuals would be effortless.

For shame. And I was starting to trust you.

15. Originally Posted by richde
I haven't come up on anything on my 6" bike that I can't maneuver around, and you don't hear about anyone who has. Yes, theoretically, it's possible...but realistically, it doesn't happen. Even if it did, those situations are so rare that the advantages of slacker, longer, geometry far outweigh any possible negatives.
I've stated that on some of the trails I ride, slacker, longer bikes are much more difficult to ride than the older geometry. You can, but you have to slow down more to make the turns. One of us is lying...

Also, a skilled rider can ride "old" geometry on just about every trail just fine. They probably won't be setting any PR's or KOM's, but why would so ebody waste their time keeping track of that, anyway?

16. What exactly is new geometry? I get longer top tube, slacker head angle, maybe lower bottom bracket and steeper seat tube angle. What else?

17. Originally Posted by MikeDee
What exactly is new geometry? I get longer top tube, slacker head angle, maybe lower bottom bracket and steeper seat tube angle. What else?
Short CS. Short enough ST to run a 6" dropper. Longer reach. Lower stack.

18. Seems new school geo is about having the BB and grips further behind and as low as possible in relation to the front axle without making the wheelbase too long, and also more standover. It's touted as being more confidence inspiring and stable--I can't argue that less endo risk and more testicle clearance can lead to those feels. Less endo risk can mean more front brake usage and, when used to address the common mistake of entering corners with too much speed, can improve cornering ability greatly. With a rearward weight bias around 65:35 (rear:front weight distro) and a short stem, you can hang even more weight off the back before you hit the end of your rope.

19. Satire aside, if people were really interested in performance, they'd be considering how angular momentum plays in all these figures, and that requires looking at the mass attached to each axle, the distance from the axles to the different points where mass is centered (rider contact points like saddle, BB, grips, head tube). They'd also consider other factors like where the rubber hits the ground in relation to the steering axis (mechanical trail), and figures like the BB drop.

Just to prime people up on how to see angular momentum, look at everyone's fav measurement, the chainstay length. The shorter it is, the less force it takes to rotate it. It's flickable in a lateral rotational axis, but it also moves easily in a vertical rotational axis, forcing you to pump the terrain, else take strong feedback, which typically is force going into your lower back, even if you have rear suspension. Putting a 1000+g Minion DHF or Trail King, 500+g larger diameter rim, CK or Onyx hub, thru-axle, big pie plate 10/11 spd cassette, heavy chain, and heavy brake on the rear wheel, results in a lot of inertia to get moving, so vertical forces move it up less when hitting obstacles, but it's also harder for you to whip it. This is why some DHers say bikes can be too light. Same goes with the front, the further away the front is from the rider, the more force it takes to deflect it at odd angles, and the less you would be compelled to pump it (less effective as well), though you would probably want to keep it in check in case it wants to float with less weight on it, as a tire in the air isn't giving you traction and control.

It's no wonder people seem to prefer a fatter heavier tire up front and a lighter one in the rear (though, a heavy one on the back for regularly plowing rough sections is acceptable) on these new school bikes, while people riding easy-riding bikes like the SB95, Sultan, the other 100-125mm 29er FS bikes with 445+mm CS are perfectly fine with similarly lightweight tires front and back. These easy-rider bikes don't really ride any worse on the DHs than the new school ones, more often being called bad because they make it too easy--too often I find myself hitting the brakes on my old 29er in order to not rear ending someone on a new school geo bike, and far out-lasting them as well.

I wonder how people saying they want new school geo, actually just want old school 26" ride handling feel with updated tech that isn't considered to be dying... those sub 24-lbs 26" 5-6" travel FS bikes were, and still are, crazy fun, esp with dialed susp and good tires. IMO, old school 26" + "old school" 29er quiver. 17.5" CS is not bad (see Ripley, SB6c, etc.). I think it's sad to see brands like Trek go short CS across the board. I wonder what their marathon and comfort seekers will go for. The old HTs and the Remedy 29 are the only MTBs left with CS longer than 17.3" for 2016, from what I can tell from a glance.

I'm not anti-new school, I'm pro-choice and anti-misinformation. Find myself ranting more and more because I'm not happy with all the misinformation fueling this popularity contest. Please don't trade in your long CS bikes for this new trend if you like regularly doing 2.5+ hr exploration rides in comfort.

20. Originally Posted by Varaxis
Seems new school geo is about having the BB and grips further behind and as low as possible in relation to the front axle without making the wheelbase too long, and also more standover. It's touted as being more confidence inspiring and stable--I can't argue that less endo risk and more testicle clearance can lead to those feels. Less endo risk can mean more front brake usage and, when used to address the common mistake of entering corners with too much speed, can improve cornering ability greatly. With a rearward weight bias around 65:35 (rear:front weight distro) and a short stem, you can hang even more weight off the back before you hit the end of your rope.
Hanging off the back of this style of bike will put you on the ground, especially in corners. That takes too much weight off the front wheel, leading to washouts. My first experience with this kind of geometry was on a Yelli Screamy, which is kind of an extreme example, at least 4 years ago. It was obvious right from the start that I needed to change some of the ways I'd gotten used to riding a bike.

You're absolutely right about letting you safely use more front brake, and I think that's a good thing. But the front brake won't have a lot of effect until you start driving that front wheel. What this kind of frame does is let you really get forward and drive the front wheel without putting yourself in an endo-prone position. It has to be really steep for me to get too far behind the saddle anymore- a couple of the famous rollers at Bartlett's Wash, for example. Even on a 35-40% fall line we ride a lot, I'm not really that far back (on a Prime). Gotta keep that wheel biting.

I'm not generally a RC fan and I disagree with a lot of his positions, but a few years ago he wrote a discussion piece on PB in relation to WC DH, comparing the off the back style of Sam Hill to the more forward style of Aaron Gwin, and how each related to frame geometry and pedal types. At that point (pre-Specialized) it seemed like Hill was the past and Gwin was the future, but it was still an interesting read.

21. While I'm all for balance in everything, and that quote was me being tongue-in-cheek, being behind the saddle to not go over the bars when braking was what I was getting at, as being in such a position when entering the turn leads to those washouts you speak of, but being rearward on a steep downslope actually gets you more centered. I remember writing about how long CS actually helps keep you better centered on steep climbs than short CS. I figure I can use the same pic to sort of show how the relationship between the axles and contact points works.

Put the steering on the other side, with the bars under where his ass currently is, then flip his ass to the other side of the green line (green line shows contact point of lower wheel, along same axis as gravity, to show the relation of rider CoG to it) and extend his arms, and you got an exaggeration of new school geo with long slack front and short rear.

I will look for that RC article, as want to see what kind of controversy it stirs up. Edit: was this it? The End of Flat Pedals at World Cup Downhills? - Pinkbike

Found a pic to show how it's nice to have the lower wheel way out there on steeps, going the other way, and have your body's CoG somewhere between the axles, in relation to the pull gravity:

22. Originally Posted by evasive
Hanging off the back of this style of bike will put you on the ground, especially in corners. That takes too much weight off the front wheel, leading to washouts. My first experience with this kind of geometry was on a Yelli Screamy, which is kind of an extreme example, at least 4 years ago. It was obvious right from the start that I needed to change some of the ways I'd gotten used to riding a bike.

You're absolutely right about letting you safely use more front brake, and I think that's a good thing. But the front brake won't have a lot of effect until you start driving that front wheel. What this kind of frame does is let you really get forward and drive the front wheel without putting yourself in an endo-prone position. It has to be really steep for me to get too far behind the saddle anymore- a couple of the famous rollers at Bartlett's Wash, for example. Even on a 35-40% fall line we ride a lot, I'm not really that far back (on a Prime). Gotta keep that wheel biting.

I'm not generally a RC fan and I disagree with a lot of his positions, but a few years ago he wrote a discussion piece on PB in relation to WC DH, comparing the off the back style of Sam Hill to the more forward style of Aaron Gwin, and how each related to frame geometry and pedal types. At that point (pre-Specialized) it seemed like Hill was the past and Gwin was the future, but it was still an interesting read.

Regarding weighting the front wheel...

Steep STAs, long TTs, and slack HTAs- combined, they put the front wheel way out there. Makes it hard to weight without a lot of body English. Still not ideal in the tight and twisties, IMO.

23. I built a 2015 Norco Range Carbon 7.2. I'd say it is textbook new geo - 800 mm bar, 50 mm stem, slack 160 mm fork (66 degree HA I believe), super short chain stays, etc.

It took me a while to finally get used to it and I have only recently concluded that it is the cause of my massively screwed up shoulder (MRI in a week). Climbing, it's great. Downs standing on the pedals, great. But flats where I pedal seated with my dropper fully extended, result in a HUGE amount of weight on my hands. I was out tonight and actually started wondering if maybe my core strength could be a little sketch (not holding my torso more upright with less weight on my hands). I am going to start blasting crunches and planks tomorrow, but really, I'm in great shape and I have never previously had this problem with a bike or otherwise. I am thinking it's a combo of the wiiiiiiiide bar, looooooong top tube and super low front end (even though it's a 160mm fork, it rides really low in the front).

Maybe I am wrong on all this, but I don't think so.

24. I am confused, does the new geo put the rider in a more stretch out or upright position on the bike? I am thinking TT gets longer, but stems get shorter? Thanks

25. Originally Posted by bob_m
I am confused, does the new geo put the rider in a more stretch out or upright position on the bike? I am thinking TT gets longer, but stems get shorter? Thanks
Depends a little bit, but generally more upright. Depending on the seat tube, the cockpit could be smaller, rather than longer. When I went from a WFO to a Prime, my ETT shortened by 12mm (~1/2") but the reach actually lengthened by 5mm. It's because of the steeper STA. If the bike has a slacker STA, then the ETT may very well be longer and have a more stretched out fit when in the saddle.

mtnbkrmike- I think you're right. I feel the same thing with my Prime, although not to the point of causing discomfort. I love the geometry for an AM bike. For a XC bike that I'd spend more time riding on rolling trails, I would want a more stretched out cockpit, and a slacker STA. So now I tend to ride with my saddle a little lower to alleviate that when I'm on the level. If you're watching the TdF, though, you'll notice that road saddles have come down a bit in the last few years, interestingly. A couple years ago I was talking to a mechanic in a booth at Outerbike and he mentioned pro road saddles has dropped an average of 2cm in the last few years. Sounded like a guesstimate, but that's what it looks like on the TV.

26. Originally Posted by mountainbiker24
I've stated that on some of the trails I ride, slacker, longer bikes are much more difficult to ride than the older geometry. You can, but you have to slow down more to make the turns. One of us is lying...

Also, a skilled rider can ride "old" geometry on just about every trail just fine. They probably won't be setting any PR's or KOM's, but why would so ebody waste their time keeping track of that, anyway?
The majority of riding isn't super tight and twisty though, once you're actually rolling instead of doing parking lot tricks, that's where the new geo shines.

Your argument is similar to the idea that 29'ers are slower because of the increase in the mass of the wheels. They both may be true, in equally limited circumstances, but the advantages far outweigh the negatives.

Just fine doesn't mean just as well either, which is the point of this conversation.

27. Originally Posted by mtnbkrmike
I built a 2015 Norco Range Carbon 7.2. I'd say it is textbook new geo - 800 mm bar, 50 mm stem, slack 160 mm fork (66 degree HA I believe), super short chain stays, etc.

It took me a while to finally get used to it and I have only recently concluded that it is the cause of my massively screwed up shoulder (MRI in a week). Climbing, it's great. Downs standing on the pedals, great. But flats where I pedal seated with my dropper fully extended, result in a HUGE amount of weight on my hands. I was out tonight and actually started wondering if maybe my core strength could be a little sketch (not holding my torso more upright with less weight on my hands). I am going to start blasting crunches and planks tomorrow, but really, I'm in great shape and I have never previously had this problem with a bike or otherwise. I am thinking it's a combo of the wiiiiiiiide bar, looooooong top tube and super low front end (even though it's a 160mm fork, it rides really low in the front).

Maybe I am wrong on all this, but I don't think so.
Sounds like a bar/seat height relationship issue.

Short stems should be cancelled out by wider bars, leaving your upper body in pretty much the same position. Your hands are just further out instead of further forward. Wider bars do make leaning the bike to turn feel more natural though.

28. Originally Posted by richde
Sounds like a bar/seat height relationship issue.
Which can be caused by the intersection of short stack / steep STA.

29. Originally Posted by evasive
When I went from a WFO to a Prime, my ETT shortened by 12mm (~1/2") but the reach actually lengthened by 5mm. It's because of the steeper STA.
I can see how the ETT (E in pic) would change as the angle of the seat tube changes but it seems reach (M in pic) would remain the same? Thanks

30. What does ETT matter if you can slide the seat where you need it for optimal power and chain stays remain the same?

My position has been pretty much KOP for 30 years independent of the bike. I pedal for power delivery for the majority of the time I pedal, not for special cases like climbing or descending, which we do a lot here on the left coast. Special case demands are much less statistically frequent. Why would one set up a bike for that?

My weight is distributed to hands, feet, butt. Yet the main balance and control is at the balls of my feet (the primary athletic demand for just about any sport but swimming) which reduces arm and butt fatigue. When I need to "handle" the machine for specific sorts of challenges I slide forward or back, use the inside of my thighs, get out of the saddle, get weight low and behind the bars, get weight off-center, lean forward; all for placing the center of gravity where needed.

I notice that so many riders simply plant their can on the saddle and it's job done. Their biggest fear is going OTB but the most frequent problem I see in riders is when they get out of the saddle for handling that situation they get above their saddle, not back; recipe for OTB. As such, modern bikes put hands higher and further back behind the front axle. Longer travel and short stems abound.

Old school set-ups, born of road, rigid, and HT, demanded very high levels of skill to command in challenging situations. Maybe modern geo has gone where it has to bring performance more within reach for a larger number of people. That, in turn, has brought riders out into more challenging types of terrain where failure is more costly for a larger number of riders and other trail users.

That is not to say that the evolution of bikes has not made riding better. I love my carbon dually but its geometry is not the thing that makes it sing.

31. Originally Posted by Berkeley Mike
Old school set-ups, born of road, rigid, and HT, demanded very high levels of skill to command in challenging situations. Maybe modern geo has gone where it has to bring performance more within reach for a larger number of people. That, in turn, has brought riders out into more challenging types of terrain where failure is more costly for a larger number of riders and other trail users.
The idea that it only benefits beginners is where the conversation goes completely off the tracks.

More confidence helps every rider, whether it's due to tires, brakes, suspension, geometry or accessories like dropper posts. They all allow you to be more confident and push the limits of what you're capable of. Yes, you can do the same things with an old bike, but it's slower, harder and downright terrifying at times. That's why people at the top of the sport use all those things.

Oh look, another step towards slacker HTAs, longer reach and short chainstays: http://www.redbull.com/en/bike/stori...=1331730540730

But what do those guys know.

32. I've mentioned this in other threads, but there's a limit to how much you can adjust your saddle position. In my case, it's not very far. First of all, I have a dropper post. Offset isn't an option. Secondly, as a 200+ lb rider, my saddle is centered on the rails. Otherwise they bend.

33. I honestly think alot of it comes down to what new frames are designed to do, vs what old school was.

Marketing a big bike shredding downhill is a lot easier and more profitable than promoting a rigid pushing on some dirt.

For me and a lot of people, a rigid is what makes sense for what is out the front door, and a rigid can be had and maintained on the cheap. Big bikes with big suspension push up the price tag, because the tech is more complex and proprietary, and because the cost of maintenance is higher. Every node of the mtb industry makes more off big bikes. The new geo is just the evolution of full suspension bike designs, which are young compared to modern bicycles in general.

I am not ashamed that I mash up fire roads, gravel, country roads and some non-gnar. I do it on 2 bikes with 71+ head angles. It is a different type of challenge to stand and mash on loose gravel and push it on the dirt road for a couple hours at sunset. That is what riding is in my area. I used to have a couple trail systems within 5 - 7 miles, but have moved, so my bikes and riding have changed, gone back in time if you will.

I feel like new mountain biking is getting closer to skiing, where you put your specialized gear in your car and drive somewhere to use it. Doesn't make alot of sense to me, when the option to ride something out the door is there for most folks.

34. Why is the reach measurement so important, you would think ETT would affect the sitting rider more? In other words, what can you learn from Reach that you can't learn from ETT? Thanks

35. Originally Posted by bob_m
Why is the reach measurement so important, you would think ETT would affect the sitting rider more? In other words, what can you learn from Reach that you can't learn from ETT? Thanks
Reach and stack will tell you how the bike fits while standing.

36. Originally Posted by Berkeley Mike
...As such, modern bikes put hands higher and further back behind the front axle. Longer travel and short stems abound...
I need to solve the problem I have with way too much weight on my hands with my dropper fully extended. From the recent posts I have read (including yours), I assume this is not a product of the "new geo" design, but something peculiar with my bike. That said, I would have thought that my 2015 Norco Range was a textbook example of the new geo design, exhibiting every single aspect of the whole "modern geo" thing.

37. Originally Posted by richde
The idea that it only benefits beginners is where the conversation goes completely off the tracks.

More confidence helps every rider, whether it's due to tires, brakes, suspension, geometry or accessories like dropper posts. They all allow you to be more confident and push the limits of what you're capable of. Yes, you can do the same things with an old bike, but it's slower, harder and downright terrifying at times. That's why people at the top of the sport use all those things.

Oh look, another step towards slacker HTAs, longer reach and short chainstays: Marco Fontana's Cannondale F-Si Carbon race bike

But what do those guys know.
Those guys? As in Redbull? Next to nothing, apparently.

The article messed up a couple of major points. First, the HTA is not 67.5 degrees.

Second, the geometry of that bike is hardly unique amongst XC frames. Superfly, Scale, etc. share very similar ACTUAL (non-fabricated by Redbull) dimensions.

Last, the best bike handler in the (XC) world uses a non-stock, custom 71 degree HTA on his Scale and Spark 700 frames.

38. Originally Posted by richde
The idea that it only benefits beginners is where the conversation goes completely off the tracks.

More confidence helps every rider, whether it's due to tires, brakes, suspension, geometry or accessories like dropper posts. They all allow you to be more confident and push the limits of what you're capable of. Yes, you can do the same things with an old bike, but it's slower, harder and downright terrifying at times. That's why people at the top of the sport use all those things.

Oh look, another step towards slacker HTAs, longer reach and short chainstays: Marco Fontana's Cannondale F-Si Carbon race bike

But what do those guys know.
I wonder if that's the reason their results have slipped. Slacker HTA is ok in my book, esp if you can adjust the trail to tame the stronger wheel flop and auto-centering effects. I'm okay with a bit longer reach combined with short stem, but it seems to be getting too extreme for short folks, but welcomed by tall folks. Short CS is way overhyped, propped up on top of a mountain of misinformation.

The main reason I like slack HTA is how it lowers the front end and increases front center, without really affecting fit negatively. Extending a fork to get slacker HTA is something I wouldn't really do, since that affects the rest of the bike in not totally positive ways. It's something I'd consider to raise a low BB a bit though. There's some misinformation out there that makes people think slack HTA corner better when leaned, but that's a misconception. Anything that spins forward will turn towards the direction it's leaned (ex. spiral coin wishing well), but in the case of slackening out a HTA, I'd say it makes it harder to turn as the auto-centering effect of the wheel trailing behind the steering axis too much actually resists turning, wanting to straighten out. If fork manufacturers were more willing to adjust offset, we would see even slacker HTAs and lower stack heights for longer travel bikes for riding both up and down the mtn.

Short CS is actually anti-beginner, IMO. Longer is more forgiving, both up front and rear. The shorter it is, the more input the rider needs to give to keep things smooth and under control. They would need to implement more advanced skills that actively weight and unweight the rear to experience a smooth and controlled ride, while a rider on longer CS can focus on pedaling. Short CS is cool and all for advanced riders that actually don't want an easier ride, and want to pump everything. Sorry to those that read this and now can't unread it, but all that pumping works your "woman on top (of man) in bed" leg and hip muscles and skills really well.

Old Norba XC geo had short CS too. Their making things as light as possible was a big driving factor behind the designs, as shorter stays and a shorter top+downtube vs a long stem netting a lighter overall bike. The lightness of the bike, plus the super short wheelbase made them way more flickable than anything today. It also made them buck wildly in the bumps too. The rougher courses of today demand longer geo not only in front, but in the rear too. You really had to be a good rider back then to handle these bikes. The old pros say that the changes in bikes these days make things way too easy in comparison. "New school" geo back then was marketed as "Genesis" geo, which pushed the front center out more, which was a very welcome change, IMO.

New school now is just old shit all over again, with the attempts at modern geo becoming bad-mouthed being called old school geo for some reason... rather than new school, we need a whole new generation of geo, one that doesn't merely have one basic design for a middle rider size, that then spawns other sizes with minor changes between sizes to fit short and tall, based on ~1" more TT length and 1.5" - 2" more seat height, and 1/2" - 1" more head tube height. Need someone to unlock that fork offset figure, to really open up this path though. I wonder if some futuristic design will have the front lean independently of the bike, maybe needing 2 smaller wheels up front, but I digress...

39. I've asked about this all the time, but the fact is, to do that would require some serious capital to have all the varying length toptubes, chainstay and seatstays for the various heights.
It's why despite everyone loving on the super short CS lengths, I am quite happy with my 17.3" on my Phantom as I'm 6'2" and almost ontop of the rear axle already, can't imagine how it would be with a 16.5" stay length.

Only thing I would like to change on my current bike is to have the STA slacked out by 1.5-2 degrees so I can get the saddle where I want, relatve to the BB without having to resort to serious setback posts and sadddles back as far as they should go, would make running a dropper a lot easier.

Originally Posted by Varaxis
......New school now is just old shit all over again, with the attempts at modern geo becoming bad-mouthed being called old school geo for some reason... rather than new school, we need a whole new generation of geo, one that doesn't merely have one basic design for a middle rider size, that then spawns other sizes with minor changes between sizes to fit short and tall, based on ~1" more TT length and 1.5" - 2" more seat height, and 1/2" - 1" more head tube height. Need some unlock that fork offset figure, to really open up this path though. I wonder if some futuristic design will have the front lean independently of the bike, maybe needing 2 smaller wheels up front, but I digress...

40. Originally Posted by bob_m
Why is the reach measurement so important, you would think ETT would affect the sitting rider more? In other words, what can you learn from Reach that you can't learn from ETT? Thanks
A lot of bikes have bent seat tubes and seat tubes that don't intersect the BB. To use technical terms this makes ETT measurements "whacked". The ETT is measured at a certain height and when buying another hardtail with a standard 73 degree STA where your saddle ends up is predictable. Once that seat tube is bent or doesn't intersect the BB that throws off the ST angle above and below the point the manufacturer picked. This makes your top tube measurement probably quite different than an old straight seat tube hardtail. You can get your saddle where you want it on a lot of frames, but not everyone on all frames. Reach and stack don't depend on some funky seat tube angle.

41. Originally Posted by knutso
I honestly think alot of it comes down to what new frames are designed to do, vs what old school was.

Marketing a big bike shredding downhill is a lot easier and more profitable than promoting a rigid pushing on some dirt.

For me and a lot of people, a rigid is what makes sense for what is out the front door, and a rigid can be had and maintained on the cheap. Big bikes with big suspension push up the price tag, because the tech is more complex and proprietary, and because the cost of maintenance is higher. Every node of the mtb industry makes more off big bikes. The new geo is just the evolution of full suspension bike designs, which are young compared to modern bicycles in general.

I am not ashamed that I mash up fire roads, gravel, country roads and some non-gnar. I do it on 2 bikes with 71+ head angles. It is a different type of challenge to stand and mash on loose gravel and push it on the dirt road for a couple hours at sunset. That is what riding is in my area. I used to have a couple trail systems within 5 - 7 miles, but have moved, so my bikes and riding have changed, gone back in time if you will.

I feel like new mountain biking is getting closer to skiing, where you put your specialized gear in your car and drive somewhere to use it. Doesn't make alot of sense to me, when the option to ride something out the door is there for most folks.
I moved to a mtb Mecca when I retired and have a vast trail network right out my door. For me a Knolly Warden is my daily driver as it makes the most sense for the trails we have. That includes full on DH trails to a bit of milder XC. The riding is demanding and very rewarding. Previous places I've lived I resorted to a SS and even fixed MTB to make it interesting. There is more riding opportunities in more places than ever and it just keeps getting better. What has changed a lot is the proliferation of mtb specific trails as opposed to hiking trails. This has made riding more fun than ever. Also gravel grinding has become it's own niche now, so what you're doing is the latest fad.

42. Originally Posted by Travis Bickle
I moved to a mtb Mecca when I retired and have a vast trail network right out my door. For me a Knolly Warden is my daily driver as it makes the most sense for the trails we have. That includes full on DH trails to a bit of milder XC. The riding is demanding and very rewarding. Previous places I've lived I resorted to a SS and even fixed MTB to make it interesting. There is more riding opportunities in more places than ever and it just keeps getting better. What has changed a lot is the proliferation of mtb specific trails as opposed to hiking trails. This has made riding more fun than ever. Also gravel grinding has become it's own niche now, so what you're doing is the latest fad.

Got any pics/videos of your part of the Pac NW/BC, showing the purpose built mtb trails and all the things you can pump? I need some inspiration for the trails down here.

43. Originally Posted by knutso
I honestly think alot of it comes down to what new frames are designed to do, vs what old school was.

Marketing a big bike shredding downhill is a lot easier and more profitable than promoting a rigid pushing on some dirt.

For me and a lot of people, a rigid is what makes sense for what is out the front door, and a rigid can be had and maintained on the cheap. Big bikes with big suspension push up the price tag, because the tech is more complex and proprietary, and because the cost of maintenance is higher. Every node of the mtb industry makes more off big bikes. The new geo is just the evolution of full suspension bike designs, which are young compared to modern bicycles in general.

I am not ashamed that I mash up fire roads, gravel, country roads and some non-gnar. I do it on 2 bikes with 71+ head angles. It is a different type of challenge to stand and mash on loose gravel and push it on the dirt road for a couple hours at sunset. That is what riding is in my area. I used to have a couple trail systems within 5 - 7 miles, but have moved, so my bikes and riding have changed, gone back in time if you will.

I feel like new mountain biking is getting closer to skiing, where you put your specialized gear in your car and drive somewhere to use it. Doesn't make alot of sense to me, when the option to ride something out the door is there for most folks.
Its come back around to what I've always thought...

The trail dictates what is the "best" bike. Use the right tool for the job. I'm not buying that the "new geo" is better for all riding - but rather it is getting to the far end of the spectrum that favors fast, open, descent oriented trails - not slower, pedally tight, twisty, tech. But the new geo is a good thing because for too many years mountain bikes were subjected to road biking standards. We are now swinging the pendulum away from roadie standards/geo.

44. Originally Posted by Travis Bickle
I moved to a mtb Mecca when I retired and have a vast trail network right out my door. For me a Knolly Warden is my daily driver as it makes the most sense for the trails we have. That includes full on DH trails to a bit of milder XC. The riding is demanding and very rewarding. Previous places I've lived I resorted to a SS and even fixed MTB to make it interesting. There is more riding opportunities in more places than ever and it just keeps getting better. What has changed a lot is the proliferation of mtb specific trails as opposed to hiking trails. This has made riding more fun than ever. Also gravel grinding has become it's own niche now, so what you're doing is the latest fad.
Right on!! Nice move!!

Not sure they can call gravel roads a fad ! It's the definition of old school

45. Originally Posted by richde
The idea that it only benefits beginners is where the conversation goes completely off the tracks.
I see your point but I'm not talking about beginners. What highly skilled riders/racers do it another issue altogether. Putting those bikes on an average rider makes a whole 'nother set of thing possible.

The point was specificity. Slack head tube angles are for a specific kind of riding, not a panacea for every type of riding. Used by a a modest rider it is like riding a bumper car. Even my high zoot bike adds that quality to my own ride; giving me the ability to do things I might not do on my steel HT racer. I bought it for that reason. More travel (a screaming 100mm), more damping, more sophisticated suspension system, better brakes, lighter weight, less stress/fatigue, more fun.

But it is the same XC geometry I have been riding for years.

Funny, we've had this discussion many times with the shop guys that support our advocacy group. Everyone wants to be ready for Mammoth or Downieville or Whistler. Yet our surveys show that 85% of riding is done in local parks ridable on an HT or rigid. The other riding is easily duoable on your basic XC geo dually. So why buy a bike for 5 rides a year? What need the "new geo."

46. Originally Posted by knutso
Not sure they can call gravel roads a fad ! It's the definition of old school
They call the caveman diet a fad, despite it being as old as it gets.

Only needs a bunch of people crazy about sharing their experience about it, and making a big deal about it as if it made a huge positive impact on their lives, to make into a fad. For example, "Short cs are the bomb! I was skeptical, but now that I've drank the Kool-Aid, I gotta say it's a game changer! Just look at how Aaron Gwin is dominating on them. Who wants a ground hugging limo that makes even the gnarliest rock gardens and brake scorching descents on my trails as boring as a trip on bike path at the park, which get stuck trying to get around switchbacks? Ever since I got my new Bagweale BaM-X 160 Duo-Link (patent pend.) bike, I'm cranking whips, drifting and roosting, floating over rock gardens, and manualing over nothing just to show off to others, since riding with wheels sliding or off the ground is rad, spelled with a F, U, and N. If 16.9" is this good, imagine 15" like on some of them DJ bikes! Check out my latest bike build pic and ride footage vid, yo~. P.S. that those rock gardens and descents are gnarlier and steeper in RL than they look in the vid."

47. All I can say is I can ride one of my newer bikes almost all day and feel fine but if I spend 1 hour on my GT from the 90's it feels like cruel and unusual punishment and leaves me in pain for hours.

48. I hear you but what does that have to do with geometry?

49. F*ck marketing.

50. I just got a huge lump in my throat.

51. Originally Posted by Berkeley Mike
I see your point but I'm not talking about beginners. What highly skilled riders/racers do it another issue altogether. Putting those bikes on an average rider makes a whole 'nother set of thing possible.
Not true, someone with no preconceived notion of what is "right" or "wrong" will just ride it, and it will become part of the learning process. It's the people who are unable (slow learners) or unwilling (the way I do it is right, damn what everybody else says) to change that have problems.

Originally Posted by Berkeley Mike
The point was specificity. Slack head tube angles are for a specific kind of riding, not a panacea for every type of riding. Used by a a modest rider it is like riding a bumper car. Even my high zoot bike adds that quality to my own ride; giving me the ability to do things I might not do on my steel HT racer. I bought it for that reason. More travel (a screaming 100mm), more damping, more sophisticated suspension system, better brakes, lighter weight, less stress/fatigue, more fun.
Nope, bikes have gotten slacker, chainstays have gotten shorter because the people who actually design bikes have discovered that it simply works better. Maybe if you know better, you can make a killing in the bike business by making that people "actually" want. But, for the time being, I'll put my faith in people who do this sort of thing for a living.

Originally Posted by Berkeley Mike
But it is the same XC geometry I have been riding for years.

Funny, we've had this discussion many times with the shop guys that support our advocacy group. Everyone wants to be ready for Mammoth or Downieville or Whistler. Yet our surveys show that 85% of riding is done in local parks ridable on an HT or rigid. The other riding is easily duoable on your basic XC geo dually. So why buy a bike for 5 rides a year? What need the "new geo."

"Ridable" does not mean that you're using the right tool for the job. If a certain geo has no negative effects, not "ridable" in comparison, but no effects in one situation and is significantly better in others, the choice is pretty clear.

I have a friend that is big into off-road unicycling, but I'm never, ever, going to suggest that since something is "ridable" on a unicycle, that it's "good enough" or even a realistic suggestion. Lots of trails have been ridden for 20 years or more, but it doesn't mean that the original bikes that could be ridden on those trails is the better choice.

Also, nobody gives a damn about your "surveys." The people I know with slacker, longer travel bikes use them where it works, and if people can only afford one bike, they should always buy the bike that works in the situation where they want it to work the most. Just because you can't get to a more DH-orientated trail more than a few times a year, it doesn't mean that you should just buy an XC bike because that's what you're stuck riding the majority of the time.

Sounds like some of you people would be happy in the 26" forum with everybody else who knows better than the professionals (designers and racers).

52. Originally Posted by richde
Not true, someone with no preconceived notion of what is "right" or "wrong" will just ride it, and it will become part of the learning process. It's the people who are unable (slow learners) or unwilling (the way I do it is right, damn what everybody else says) to change that have problems.

Nope, bikes have gotten slacker, chainstays have gotten shorter because the people who actually design bikes have discovered that it simply works better. Maybe if you know better, you can make a killing in the bike business by making that people "actually" want. But, for the time being, I'll put my faith in people who do this sort of thing for a living.

"Ridable" does not mean that you're using the right tool for the job. If a certain geo has no negative effects, not "ridable" in comparison, but no effects in one situation and is significantly better in others, the choice is pretty clear.

I have a friend that is big into off-road unicycling, but I'm never, ever, going to suggest that since something is "ridable" on a unicycle, that it's "good enough" or even a realistic suggestion. Lots of trails have been ridden for 20 years or more, but it doesn't mean that the original bikes that could be ridden on those trails is the better choice.

Also, nobody gives a damn about your "surveys." The people I know with slacker, longer travel bikes use them where it works, and if people can only afford one bike, they should always buy the bike that works in the situation where they want it to work the most. Just because you can't get to a more DH-orientated trail more than a few times a year, it doesn't mean that you should just buy an XC bike because that's what you're stuck riding the majority of the time.

Sounds like some of you people would be happy in the 26" forum with everybody else who knows better than the professionals (designers and racers).
Great, thoughtful responses. We just come from a different place. I've been training riders and leading rides for a long time and this is how I see things. My surveys are purposed for use in advocacy for informing land managers about usage and how we support local riders most effectively. My resources in the industry have been really helpful, too. That is real-time experience I have learned to trust.

As far as what's ridable. I hold my own.

Ride well.

53. Originally Posted by Travis Bickle
However stem length effects handling and ones ability to shift weight to where it's needed. If you have to go long just for fit then maybe the frame is too short.
In general, does a longer stem slow steering, is that why you can use wider bars with a short stem and break even. If true, what is the real advantage of a short stem and wider bars over the former?

Very interesting thread, trying to absorb it all,

Thanks

54. Originally Posted by bob_m
In general, does a longer stem slow steering, is that why you can use wider bars with a short stem and break even. If true, what is the real advantage of a short stem and wider bars over the former?

Very interesting thread, trying to absorb it all,

Thanks
Wide bars give you more leverage, which equals more stability.

55. Originally Posted by Varaxis
...imagine 15" like on some of them DJ bikes!
15" is for beginners.

Real men ride 14.3.

Apparently tireless is the new tubeless.

But getting back on topic, if only fractionally more serious, a 'new geo' bike arrived in my garage today. 443mm reach, 445 seat tube, 64.5 HTA, 438/422 chainstays (flip chip). Opinions arriving Sunday after I have a chance to ride it a while. Maybe even up some hills.

NS Bikes - Soda Evo Air - Freeride / Bike park / Mini DH

56. Originally Posted by jazzanova
Wide bars give you more leverage, which equals more stability.
But would it (shorter stem) also shift your weight a bit more to the center of the bike?

57. Originally Posted by bob_m
But would it (shorter stem) also shift your weight a bit more to the center of the bike?
Depends whether you're talking about the customer or the designer...

If "shorter stem" means putting a shorter stem on the same frame, then yes.

If "shorter stem" means making a frame with a correspondingly longer reach, then no.

58. Originally Posted by bob_m
But would it (shorter stem) also shift your weight a bit more to the center of the bike?
Wider bars will negate the effect.
1cm difference in stem length = 2cm difference in bar
In other words, if you use 1cm shorter stem, you should use 2cm wider bars in order to maintain the same position over the front.

59. Originally Posted by bob_m
But would it (shorter stem) also shift your weight a bit more to the center of the bike?
More to the back, esp if you're not tucked forward aggressively. Your weight is already rearward naturally on the bike, so to shift it more to the center, you would need to get more weight up front, which means lower and longer stem with bars that put grips further away from shoulder width length apart (either super narrow or super wide), and/or with less rise (or more drop) to pull you even more forward.

60. Whoah, this thread restores my faith in forums.

61. ## New VS Old Geometry

Originally Posted by jazzanova
Wider bars will negate the effect.
1cm difference in stem length = 2cm difference in bar
In other words, if you use 1cm shorter stem, you should use 2cm wider bars in order to maintain the same position over the front.
Is that really true? My new wider bars have a 9 degree sweep vs. the older, shorter ones having 5 degree. Although my hands are farther apart, they are also further back.

Is there a calculator for this (similar to stem calculators)?

62. Originally Posted by MikeDee
Is that really true? My new wider bars have a 9 degree sweep vs. the older, shorter ones having 5 degree. Although my hands are farther apart, they are also further back.

Is there a calculator for this (similar to stem calculators)?
Handlebar sweep is not a tool for fitting a bike to size. It is best suited to enhancing the static state of the bike to the rider; more back sweep to promote quicker turn in, less to promote greater on-center maneuverability. Then - each can be summed by simply being comfortable, but they know. They know...

63. There is NO hard/fast rule about bar and stem dimensions. Via trial and error - go with what is most comfortable with you. I got lucky, with running a 730mm bar @5 deg sweep and 70mm, 7deg stem, the first time out. YMMV....

64. This seems to be on topic.

Jon from What Mountain Bike built a downhill-slack hardtail so long he could only reach the bars by bolting them right to the top of the steerer. It looks awesome, but how does it ride?

65. You may have heard of Kirk Pacenti, the Godfather of the modern 650b mountain bike wheel. Here is his view on geometry and the thinking behind his PDent stem and bars.

PDent

66. I'm glad that flat bars are offered in similar dimensions and similar ergonomics to some of the popular risers, as I don't need the bars any higher on bigger wheeled bikes. Glad to see stack heights dropping more and more, back down to 600mm and less for someone 5'7". I think that was another reason for not liking the ROS9 and E29, since their stack is around 635mm or so, preferring the fit of my Med SJ FSR Evo 26" more (592mm). Glad to see more and more going for integrated or ZS style headsets, getting the front end lower for smaller folk. I think it's the shorter folks getting screwed here, considering how someone over 6' can really like a Santa Cruz with stack that's 1" higher or less than what's on medium size and small size (see Nomad and V10).

Forks length and HA seems to be a big one in regards to stack height. With steep HA related to XC geo, the stack height gets out of control. I'd rather ride a shorter rigid fork, than a 100mm susp fork if it means I can get the bars lower. Or just space the suspension fork down to 80. But why give up suspension when you can slack out the head tube and give the fork more offset to keep the snappy steering, giving you suspension, a longer front center, and a front end which isn't too high. The only issue is the wheelbase increase, which has both ups and downs (only down that bothers me is widening a turning radius). With susp fork axle to crown lengths having some needless length trimmed for the same amount of travel, longer travel forks become more viable, and categories associated with shorter travel susp begin to adopt 10-20mm more travel.

Shorter stems, more fork geo options, sizing axioms being questioned, shortening crank lengths and lowering BBs, longer front center, reducing wheel dish (offset dropouts, assym spoke hole drilling, etc.), shorter seat tubes for lower slammed posts, low and centered mass... what else should be looked at for new geo? Even wider Q-factor options? Thinner pedal axles? Different way to attach pedals to the crankarm, such as bearings either side of the crank arm, instead of inside the pedal body? I know I'm about to stick on pedal extenders and BikeFit ITS wedges to address how my knee wobbles inward at the top of my pedal stroke, due to how narrow my feet are spaced by the pedals. I wouldn't be against 83mm 157mm, just sticking a 1x chainring on the outside of a triple, and gaining a wider foot stance that way. I'm running a 650b Pike on my 26" and only think of the extra offset as a bonus for how I ride the bike (more XC than DH).

67. Originally Posted by Travis Bickle
You may have heard of Kirk Pacenti, the Godfather of the modern 650b mountain bike wheel. Here is his view on geometry and the thinking behind his PDent stem and bars.

PDent
In my opinion, this guys opinion on stem length effects is grossly exaggerated. Also, the 650B wheel size is a disappointment because it's only 1" in diameter greater than a 26" wheel; not 27.5" like it should be. I'm sticking to 29" wheels.

68. Originally Posted by MikeDee
In my opinion, this guys opinion on stem length effects is grossly exaggerated. Also, the 650B wheel size is a disappointment because it's only 1" in diameter greater than a 26" wheel; not 27.5" like it should be. I'm sticking to 29" wheels.
Just FYI, 26" bikes with 2.25" tires are about 26.5" and +1" gets you 27.5". Also, some tires are undersized based on their claimed widths in inches. The ETRTO measurement (ex. 59-559) can sometimes show how big a tire really is. For example, a DHF 26x2.5 EXO isn't really that much bigger than a 26x2.3 TR DHF, according to the ETRTO measurements (55/59-559 vs 58-559. The NeoMoto and earlier 650b tires were undersized, since there were no true 650b frames/forks then and they had to fit in ones designed for 26", so they were a little under 27.5". Some 26" 2.4-2.7 tires actually measure a good amount over 27".

What arguments do you have against his statements about stem length specifically? I must have missed something when I read, since I didn't find it disagreeable, though I did find it funny that he talked about getting things lower, yet showed a picture of PDent riser bar.

69. Originally Posted by MikeDee
In my opinion, this guys opinion on stem length effects is grossly exaggerated. Also, the 650B wheel size is a disappointment because it's only 1" in diameter greater than a 26" wheel; not 27.5" like it should be. I'm sticking to 29" wheels.
What setups have you tried?

70. I bought a medium Warden and one of the things I love it the low 587mm stack with a 160mm fork. Even the XL has 597mm, which may be too low for XL, but you can always get higher rise bars. You can only offset too much stack so much.

71. Originally Posted by Travis Bickle
I bought a medium Warden and one of the things I love it the low 587mm stack with a 160mm fork. Even the XL has 597mm, which may be too low for XL, but you can always get higher rise bars. You can only offset too much stack so much.
Word. I bought a medium SC TB LTC with the intention of riding it with a 140mm Pike.

After getting a rolling chassis together (frame, HS, fork, stem, bars, wheels, seat and post, cranks, pedals) I determined it was/is WAY, WAY too tall for me.

In comparison, I had the chance to demo a medium Yeti ASR-C with a 130mm Fox (yes, lower A-C), and it was significantly shorter on the front end. Most of which was made up entirely by the HT (tiny) and internal headset.

It may seem trivial, but that 46mm (8mm + 12mm stack vs. IS, 100mm vs. 90mm HTs, A-C difference (6mm?), 10mm travel difference) or so of total stack height makes a pretty profound difference. That was just sitting there.

The medium SC has a shorter TT, longer HT, and same HTA as my 100mm carbon hard tail race bike. The Yeti is a bit longer in the TT, but the bars are much closer to the position of the hardtail than they were to the SC, despite having a 30mm longer fork on it.

72. Stack is often overlooked but is a very important measurement when shopping for a bike, especially a long travel bike. Enduro 29er is supposed to be amazing but there is no way I could get those bars where I want them.

73. Originally Posted by Travis Bickle
What setups have you tried?
I've varied stem length a cm or two and couldn't tell the difference.

74. Today I swapped my 50mm for my 35 and there was a marked difference in steering quickness and descendability. Over the years I've had stems from 35mm to 135mm and bars from 560 to 780mm. Love short and wide.

75. Has anyone gone from 17.5" CS to <17" CS notice that they've gotten way more rear flats, rim strikes, and other rear wheel-related problems (inc. burps, tire malfunctions, spokes popping, tacoed rims, etc.)?

76. Anyone remember this?

77. Originally Posted by Varaxis
Anyone remember this?

April Fools - 2013

78. Originally Posted by Haint
April Fools - 2013
2015 - NS Bikes Introduces Radical New Geometry for Mountain Bikes by ns-bikes - Pinkbike

I like how they photoshopped the rear wheel being impossibly crammed in there for truly short CS.

16.9" isn't that short anyways, unless you're talking about a long 46+" wheelbase park/DH bike that is only made to be ridden for short ~5 minute runs with long rests in between. It's more like on the cusp of being long for a compact wheelbase bike like the 26" wheeled ASR5 or Blur TR, able to be ridden long distance, but more for those short shredding rides. The longer you make the stays, the more of an epic slayer it becomes, like the 17.9" CS Tallboy LT, or ultimate cushy cruiser like the 18.2" CS Turner Sultan. The sit and spin, mileage eaters types out there that don't mind actually having gears up front are probably getting confused by all the marketing showcasing these mini-DH-bikes with long fronts and short rears. Hopefully Yeti proves to some how CS length should be proportionate to find a balanced-feeling trail bike.

79. Originally Posted by Varaxis
2015 - NS Bikes Introduces Radical New Geometry for Mountain Bikes by ns-bikes - Pinkbike

I like how they photoshopped the rear wheel being impossibly crammed in there for truly short CS.

16.9" isn't that short anyways, unless you're talking about a long 46+" wheelbase park/DH bike that is only made to be ridden for short ~5 minute runs with long rests in between. It's more like on the cusp of being long for a compact wheelbase bike like the 26" wheeled ASR5 or Blur TR, able to be ridden long distance, but more for those short shredding rides. The longer you make the stays, the more of an epic slayer it becomes, like the 17.9" CS Tallboy LT, or ultimate cushy cruiser like the 18.2" CS Turner Sultan. The sit and spin, mileage eaters types out there that don't mind actually having gears up front are probably getting confused by all the marketing showcasing these mini-DH-bikes with long fronts and short rears. Hopefully Yeti proves to some how CS length should be proportionate to find a balanced-feeling trail bike.
I am not a fan of ultra-short rear stays. There's no true reward from riding a bike who's powder is kept wet, it loses appeal IMO. I think my bike has something like 17.1" stays, plenty short to loft the front end at speed, carves a stable line at speed at the same time.
Front center though, could be longer... lol.

80. The BB drop has more to do with how easy the front is to lift, than the CS. Too much BB drop makes it hard to lift. The short rear just forces you to get out of the saddle and pump the terrain with your hips/legs, else the bumps just pound your lower back and try to buck you. Short CS tends to work better with ultra active suspension (if your legs aren't active enough for a hardtail), like horst link with lower anti-squat and chain growth (ex. Knolly). If you're just going off of a drop, having room to throw your hips back is enough to keep the front up, but the further back your weight is from the front axle, the less weight is on it to be accelerated downwards, and the slower it rotates/falls downward. If you're intent at keeping the wheels on tracking on the ground for traction and control, more BB drop is actually desirable--it's a large part of what's behind that in the bike feel, that keeps you from feeling like you can be bucked off over the front or the back.

81. It certainly allows more aggressive riding as more comfort/control.

82. I have a question regarding this paragraph from single track:
"Mondraker has made a name for itself recently by pioneering the concept of Forward Geometry – the principal of keeping contact points on the bike the same, but shortening the stem and lengthening the top tube. The results, Mondraker maintains, are a more stable ride, better control on steep descents and a more ‘loaded’ front wheel that increases traction and grip in corners. You may by now have picked up a theme here: Mondraker is squarely in the business of downhill and enduro bikes. It is the latter that the new 2016 Dune model is aimed at."

They mention a "more loaded front and increased traction and grips in corners" as a result of the forward geometry.
But doesn't it need more power to keep the front down? With a slacker HA, ultra short stem and longer reach the wheel is way up there in the front and I would assume more prone to wash outs.
If one gets lazy or tired and doesn't weight the front enough...

So does the grip in this case come from the necessity to ride it from the front in order not to wash out or does the geo itself helps the grip?

83. I found that I have had to change my riding style to a more centered weight distribution. I lean down low over the stem and the bike just rips. The only time I get more rearward now is on a few ultra steep sections, or hard braking. Normal descending and especially cornering requires more weight on the front. I really want to pick up a Mondraker Vantage Frame as a 2nd bike to try the extreme reach end of the spectrum.

84. Originally Posted by jazzanova
I have a question regarding this paragraph from single track:
"Mondraker has made a name for itself recently by pioneering the concept of Forward Geometry – the principal of keeping contact points on the bike the same, but shortening the stem and lengthening the top tube. The results, Mondraker maintains, are a more stable ride, better control on steep descents and a more ‘loaded’ front wheel that increases traction and grip in corners. You may by now have picked up a theme here: Mondraker is squarely in the business of downhill and enduro bikes. It is the latter that the new 2016 Dune model is aimed at."

They mention a "more loaded front and increased traction and grips in corners" as a result of the forward geometry.
But doesn't it need more power to keep the front down? With a slacker HA, ultra short stem and longer reach the wheel is way up there in the front and I would assume more prone to wash outs.
If one gets lazy or tired and doesn't weight the front enough...

So does the grip in this case come from the necessity to ride it from the front in order not to wash out or does the geo itself helps the grip?
They are spewing the Mondraker marketing line. It is not exactly a scientific article. Your thinking is on the right track.

85. Late 80's I got something called all terrain bike, I liked how stable it was, I could twist my upper body and bike kept it's direction, it had 26" tires.

2014 I got my current 26" Trek, I like it how I can look back and bike continues straight, but with this one I can take very tight soft sand corners at speeds my brain tells me being completely impossible and with all the upgrades to bike and geometry (stem) I have made, it is now even more so, but even less scary than before.

I think that it is now bit closer to this new geometry in a way, but there is not so huge difference to late 80's bike either in my opinion, braking is about the same, except in wet it is lot better, handling is quite close, except at slow speed where it is lot better.

Surely higher level mtb might show more difference, but good is good.

I do find need to go behind the saddle on some descents though, soft fine grain sand on rather steep descent and lot of 'rails' rocks etc. in the sand, I tend to go slow and to keep speed slow I need to brake a lot, then it is needed to go behind the saddle.
With more advanced bike and better rider such might be situation where they just pedal more speed, so again different equipment and way to ride changes experience.

But I feel that differences might be rather subtle, it is not that huge change.

Nothing compared to first ride with that all terrain bike, when I was used to riding Torpedo 3 speed traditional bicycle and all of sudden I could ride on soft sand and down the hill faster than ever while having solid control (which there never was with traditional bicycle), that was big difference.

86. I too wonder what they mean about more grip in corners. The longer front center keeps the wheel on the ground more, which obviously grants greater traction over wheels in the air. Is it because the suspension is made more sensitive and front wheel's air pressure can be lowered, with less weight on it? More likely it has more traction, than less, with all things considered.

87. Really there does not keep the indicators of each measurement on full-suspension frames with me, dunno if this is a good thing or overly simplistic. There are a few rigid numbers which will provide some insight into proportions and rider weight-distribution but once the suspension comes into it's work load, the bike is all over the map. The equivalent of not-too-distant automotive new car MPG estimates being stated at 55MPH, while the national speed limit was 65.

75 in Florida.

88. Originally Posted by Varaxis
I too wonder what they mean about more grip in corners. The longer front center keeps the wheel on the ground more, which obviously grants greater traction over wheels in the air. Is it because the suspension is made more sensitive and front wheel's air pressure can be lowered, with less weight on it? More likely it has more traction, than less, with all things considered.
I'd say the main difference is in the forgiveness of the bike and how much it lets you get away with. I own a mid 90s hardtail with 20 year old geometry and have ridden its modern equivalent which is a fair bit longer & slacker. On a smooth sweeping turn they'll both get through at the same speed (within the margin of error of my bike computer) without sliding off the trail, but they do it very differently. The old bike has to be ridden with perfect weight balance or else the front end will either want to slide out or knife into the ground and high side the bike. And once either end starts sliding, you need to catch it fast or you're going down. With the new bike, it's a lot easier to get to the traction limit. The front wheel doesn't knife into the ground and high side the bike, and when the wheels do start sliding it's much easier to control the drift and ride it out.

On actual real world trails which have bumps, ruts, and all that other fun stuff, it means that I can ride much closer to the traction limits on the new bike than my old one. On the old bike, I have to leave a fair bit of margin when cornering in case I whack something I didn't see, hit a loose patch, etc. so that I can correct the line/balance and ride it out. Or sometimes the terrain is so bad that I can't get my weight set properly to carve a turn. With the new one I don't need as much margin since the bike wants to stay upright and isn't as affected by trail obstacles, a loose patch that washes out the old bike merely results in a fun drift on the new bike. And since it handles rough terrain better, it's easier to stay balanced, weight the bike properly, and drive it through the turns.

89. Originally Posted by grumpy old biker
Late 80's I got something called all terrain bike, I liked how stable it was, I could twist my upper body and bike kept it's direction, it had 26" tires.

2014 I got my current 26" Trek, I like it how I can look back and bike continues straight, but with this one I can take very tight soft sand corners at speeds my brain tells me being completely impossible and with all the upgrades to bike and geometry (stem) I have made, it is now even more so, but even less scary than before.

I think that it is now bit closer to this new geometry in a way, but there is not so huge difference to late 80's bike either in my opinion, braking is about the same, except in wet it is lot better, handling is quite close, except at slow speed where it is lot better.

Surely higher level mtb might show more difference, but good is good.

I do find need to go behind the saddle on some descents though, soft fine grain sand on rather steep descent and lot of 'rails' rocks etc. in the sand, I tend to go slow and to keep speed slow I need to brake a lot, then it is needed to go behind the saddle.
With more advanced bike and better rider such might be situation where they just pedal more speed, so again different equipment and way to ride changes experience.

But I feel that differences might be rather subtle, it is not that huge change.

Nothing compared to first ride with that all terrain bike, when I was used to riding Torpedo 3 speed traditional bicycle and all of sudden I could ride on soft sand and down the hill faster than ever while having solid control (which there never was with traditional bicycle), that was big difference.
Dude, 24 years of riding might have something to do with this success.

90. Originally Posted by aerius
I'd say the main difference is in the forgiveness of the bike and how much it lets you get away with. I own a mid 90s hardtail with 20 year old geometry and have ridden its modern equivalent which is a fair bit longer & slacker. On a smooth sweeping turn they'll both get through at the same speed (within the margin of error of my bike computer) without sliding off the trail, but they do it very differently. The old bike has to be ridden with perfect weight balance or else the front end will either want to slide out or knife into the ground and high side the bike. And once either end starts sliding, you need to catch it fast or you're going down. With the new bike, it's a lot easier to get to the traction limit. The front wheel doesn't knife into the ground and high side the bike, and when the wheels do start sliding it's much easier to control the drift and ride it out.

On actual real world trails which have bumps, ruts, and all that other fun stuff, it means that I can ride much closer to the traction limits on the new bike than my old one. On the old bike, I have to leave a fair bit of margin when cornering in case I whack something I didn't see, hit a loose patch, etc. so that I can correct the line/balance and ride it out. Or sometimes the terrain is so bad that I can't get my weight set properly to carve a turn. With the new one I don't need as much margin since the bike wants to stay upright and isn't as affected by trail obstacles, a loose patch that washes out the old bike merely results in a fun drift on the new bike. And since it handles rough terrain better, it's easier to stay balanced, weight the bike properly, and drive it through the turns.
Can you attribute the ease to a better front shock at a all? My '95 Judy and my current Fox are night and day. Same with V-brakes vs hydraulics. Wheel base is within 3/4 inch and angles within 1 degree. Stem is 20mm shorter but I am 63 not 43 anymore, too.

91. Originally Posted by Berkeley Mike
Can you attribute the ease to a better front shock at a all? My '95 Judy and my current Fox are night and day. Same with V-brakes vs hydraulics. Wheel base is within 3/4 inch and angles within 1 degree. Stem is 20mm shorter but I am 63 not 43 anymore, too.
Aerius explained it like I would've. That forgiveness is an attribute of the longer front center, wheelbase, rear center (RC/chainstay). Compact short wheelbase bikes aren't very forgiving, which is what the old Norba style XC bikes were back in the day. You had to be so skilled and experienced to handle them well. I did mention that big names from back then have mentioned that bikes these days dumb down the challenge a lot. Riding is boring without challenge, hence why some still prefer short and compact bikes, particular those with significant mtb riding experience, notably short travel bikes with short rear ends and smaller wheels. Might be faster and smoother with longer geo, but is it fun? This is why 29ers were slandered. Short CS bikes supposedly address that issue of 29ers being La-Z-boys for trails, but to me they don't make it any more challenging, it just transmits spikes of trail feedback continuously and forces me to get out of the saddle to absorb them with my legs, being less efficient and shortening my ride, making it feel more intense, but not really any faster. If I wanted my bike compact, I'd rather have it balanced, like the Ripley.

Speaking of compact vs long geo, wait for the Ripley LS reviews to come out to confirm all this. The LS will be more confidence inspiring, easier to ride at speed and through the rough that also does better than the original in the really steep downs (and ups), basically more like a mini DH bike, losing its quickness in tighter and slower trails, more contoured rolling terrain, and pumpy/flowy trails. While the LS might actually climb techy and loose stuff with less effort, it probably would pedal strike a lot more too, esp climbing up on ledges, even if its BB weren't lower (due to long front end)

92. Originally Posted by Berkeley Mike
Can you attribute the ease to a better front shock at a all? My '95 Judy and my current Fox are night and day. Same with V-brakes vs hydraulics. Wheel base is within 3/4 inch and angles within 1 degree. Stem is 20mm shorter but I am 63 not 43 anymore, too.
Forks were fairly similar, Manitou Minute MRD on my RM Blizzard vs. a RS Revelation on a 2015 Kona Explosif, if anything the old bike has the advantage here. Wheels & tires were also close enough, Conti MKII on Blizzard vs. Maxxis Ardents on the Explosif, both on WTB rims. Other than the drivetrain & frame there's barely any difference between the bikes. I swapped parts around on my bikes to make it as even as possible.

Originally Posted by Varaxis
Speaking of compact vs long geo, wait for the Ripley LS reviews to come out to confirm all this. The LS will be more confidence inspiring, easier to ride at speed and through the rough that also does better than the original in the really steep downs (and ups), basically more like a mini DH bike, losing its quickness in tighter and slower trails, more contoured rolling terrain, and pumpy/flowy trails. While the LS might actually climb techy and loose stuff with less effort, it probably would pedal strike a lot more too, esp climbing up on ledges, even if its BB weren't lower (due to long front end)
This, I think is the closest we'll get to a perfect comparison. I did test ride the Ripley last year and thought it was a fairly XC-ish fit & handling, much more so than the Mojo HD I test rode on the same day. Since I'm now older and my reflexes are slower than they used to be, and I no longer have Jedi like balance & reactions, I now prefer a more forgiving bike so that I can continue to ride fast and have fun.

93. Originally Posted by Berkeley Mike
Dude, 24 years of riding might have something to do with this success.
I don't know, I did ride that late 80's bike last time at 2005 (it was stolen then) and then didn't really ride much at all until 2013, during that time I had cheap supermarket bicycle that was not MTB and I did not like it at all, never managed to ride straight line with it and almost felt over if I took one arm off from the handle bar.

Since 2014 I have been riding Trek and first ride reminded me of that old bike.

Also what Aerius wrote seem to sound familiar, yes, front wheel does not escape so easily, it was not bad with late 80's bike either, but with Trek it is very rarely happening, I have been riding quite fast front wheel trying to slide from under me, but somehow it just stays upright, tens of feet slide and then regaining grip, on snow of course.

After moving my riding position more forward, lowering handle bar and shorter stem, I can now balance better weight to front and climbs as well as very tight corners at insane speeds seem easier.

Also it is easier to move weight around, that is perhaps what late 80's bike sucked a bit compared to my current setup in Trek, now I have possibility to move my body so much that there is really big change in weight percentage, I can put more weight to front or rear wheel, maybe one could say adjustability of weight balance is greater thus I'm getting more from my rides?

94. For me it has always been about finding the heart of the bike; where my weight was best placed to deliver power, get grip where I needed it, and flick the bike around. From there I moved my weight around as needed.

New ways of conceptualizing geo through new language explains how things work for many. I am limited by an adherence to XC geometry and how it fulfills my needs. Anything more slack or longer is not useful for me. As such, technological improvements like shocks, frame material, brakes, carbon wheels, and the like get my attention.

95. So the Scotts, GF Treks et al with the <69* HTA aren't XC then?

Originally Posted by Berkeley Mike
.......New ways of conceptualizing geo through new language explains how things work for many. I am limited by an adherence to XC geometry and how it fulfills my needs. Anything more slack or longer is not useful for me. As such, technological improvements like shocks, frame material, brakes, carbon wheels, and the like get my attention.

96. Do you guys, who are on these new geo long reach bikes with short (30mm and shorter) stems find it more difficult to weight the front?
I am talking slow speed descending and turning.
I would assume it should be easier with longer stems.
I am asking because I am fairly light at 140lbs / 5'8.5" and it might cause a difficultty and wash outs...

I am also wondering how this would be effected on, let's say 2 bikes with the exactly same geometry but the Reach/TT and HA would be different.
2 bikes with the same WB, one with 65degree HA and shorter reach, while the other ones HA around 67 degrees and longer reach.
I am curious, because most of the new long reach/WB bikes don't have the ultra slack 65 HA...

97. Originally Posted by aerius
I'd say the main difference is in the forgiveness of the bike and how much it lets you get away with. I own a mid 90s hardtail with 20 year old geometry and have ridden its modern equivalent which is a fair bit longer & slacker. On a smooth sweeping turn they'll both get through at the same speed (within the margin of error of my bike computer) without sliding off the trail, but they do it very differently. The old bike has to be ridden with perfect weight balance or else the front end will either want to slide out or knife into the ground and high side the bike. And once either end starts sliding, you need to catch it fast or you're going down. With the new bike, it's a lot easier to get to the traction limit. The front wheel doesn't knife into the ground and high side the bike, and when the wheels do start sliding it's much easier to control the drift and ride it out.

On actual real world trails which have bumps, ruts, and all that other fun stuff, it means that I can ride much closer to the traction limits on the new bike than my old one. On the old bike, I have to leave a fair bit of margin when cornering in case I whack something I didn't see, hit a loose patch, etc. so that I can correct the line/balance and ride it out. Or sometimes the terrain is so bad that I can't get my weight set properly to carve a turn. With the new one I don't need as much margin since the bike wants to stay upright and isn't as affected by trail obstacles, a loose patch that washes out the old bike merely results in a fun drift on the new bike. And since it handles rough terrain better, it's easier to stay balanced, weight the bike properly, and drive it through the turns.
Which means that with equal rider skill, the new bike will be faster...faster being an indication of better, and isn't that what this thread is all about?

98. Safer as well as faster. Amazing the mistakes my bike will eat up.

99. Originally Posted by jazzanova
Do you guys, who are on these new geo long reach bikes with short (30mm and shorter) stems find it more difficult to weight the front?
I am talking slow speed descending and turning.
I would assume it should be easier with longer stems.
I am asking because I am fairly light at 140lbs / 5'8.5" and it might cause a difficultty and wash outs...

I am also wondering how this would be effected on, let's say 2 bikes with the exactly same geometry but the Reach/TT and HA would be different.
2 bikes with the same WB, one with 65degree HA and shorter reach, while the other ones HA around 67 degrees and longer reach.
I am curious, because most of the new long reach/WB bikes don't have the ultra slack 65 HA...
On some of my bikes, it's as if the *range* of weight that the front likes for familiar turns at familiar speeds is narrower (less forgiving, requiring more focus and accuracy). It's on my slacker long travel bikes ('13 SJ FSR Evo), rather than my XC bikes (ex. '10 Superfly 100), that I feel the extra demand from. Pretty much forced to learn advanced cornering skills on the longer travel bike. Oddly enough, it became easier when I stuck a 650b Pike on it, replacing the old 26 fork (which I discovered in the 150-160 travel range, had less than normal offset at 37mm, vs 42 on the new fork), so offset/trail likely something to do with it. Probably why people say you have to lean on the slack bikes, when both works well on the XC style bike. I see Zokes have 44mm on their 26" forks--I've heard a lot of talk about how more accurately they steer compared to the competition.

100. Originally Posted by LyNx
So the Scotts, GF Treks et al with the <69* HTA aren't XC then?

I consider 69º a fuzzy edge of XC. I recall riding the Santa Cruz 5010 at 68º and it felt outside the XC range I liked, as if I was constantly pushing a front wheel. With that the wheelbase got 1" longer. The Bronson, Yeti SB75, Spot One, we also in that class but 2-3 inches longer in wheelbase. The Flux and Liteville 301 were past that. When it cam time for tight corners i felt like I was driving the family station wagon.

Keep in mind that my '95 Bontrager Racelite, very light steel, had a headtube angle of 71º and a wheelbase of 1054, 4.5 inches shorter than the Bronson. Add to that some short chain stays. You want quick? Think mountain goat uphill, jack rabbit out of turns, and flickable.

I liked the Stumpy FSR Carbon (29), Tallboy (29) and the Anthem Advance (27.5) at 69, 70.2, and 69.5 respectively. I didn't like the floppiness of the 29er wheels.

So I went with the Anthem, a 2.5" increase in wheelbase, 1.5º more slack, and 90mm stem and flat swept bars. Some of the benefit was simply less weight due to Carbon frame. It took me about 2 weeks to find the heart of the bike. Adding carbon hoops and I had a quick, flickable machine.

My hands and feet are in the same place they have always been within a few mms. Wheelbase is bigger but most of that is in the wheel size, some in the slacker head.

Maybe that is the "new" geometry folks are talking about here. I would have no trouble with shorter top tube and a longer stem, though.

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