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  1. #1
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    Dialing in Riding Position

    I know there are a lot of accomplished XC riders on here...much more than me....and I would like to tap into your thoughts on best riding position. Most don't become good riders by accident and they are vigilant about fit and set up. I also know...this is highly subjective and really a choice more than a formula. I would like to focus on XC and higher speed riding position if possible recognizing that DH is many times more upright. I have searched for general rules of thumb when it comes to best set up and have come a way with a couple of conventions. Yes, we all know how flawed conventions are and not universally applicable but here a couple:

    - When seated and looking down on a mtb, the handlebar should be out in front of the front hub by 1 inch or so.

    - Place your elbow against the nose of the saddle and your middle forefinger should end up between the steerer centerline and stem clamp center.

    According to both I am riding a bit stretched out and wondered about you guys? My handlebar is about 1.5-2" in front of my hub and my middle forefinger only extends about an inch past the steerer centerline...and I have longish arms.

    The complexity of fit relates to the elusive balance between horizontal reach and vertical drop...each collectively make up reach...i.e. distance from shoulder joint to handlebar. In my case, the top of my handlebar with sag is about even to the top of saddle. No doubt running more drop than this would require I reposition my handlebar closer to satisfy my net reach.

    Anyway, I wanted to see how close these conventions satisfy your fit? I am tempted to experiment with a shorter stem and a bit more drop to have my hands a bit closer to my body and more underneath my torso versus a more 'hammock' position of higher bars farther away and stretched out.

    Please let me know what you think.
    Attached Thumbnails Attached Thumbnails Dialing in Riding Position-mtb-reach-handlebars.jpg  

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  2. #2
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    I am currently fiddling with my set-up. I have always been comfortable with a 24.5" ETT and a 100mm 10 deg rise stem on my FS 29ers. I am no where close to my handlebars being in front of my front hub. More like 4" behind it (on my Jet9). My bars and saddle are close to the same height. My finger barely reaches over the top cap. All that being said, I am going to try a bar with more sweep and/or a shorter stem. I have been having some low back pain recently and think it may be caused by my stretched out position. We'll see.
    "No good deed goes unpunished"

  3. #3
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    Quote Originally Posted by Coach417
    I am currently fiddling with my set-up. I have always been comfortable with a 24.5" ETT and a 100mm 10 deg rise stem on my FS 29ers. I am no where close to my handlebars being in front of my front hub. More like 4" behind it (on my Jet9). My bars and saddle are close to the same height. My finger barely reaches over the top cap. All that being said, I am going to try a bar with more sweep and/or a shorter stem. I have been having some low back pain recently and think it may be caused by my stretched out position. We'll see.
    I don't know Coach...I think you missed how the convention works. It is 'line of sight' from rider on the bike seeing the handlebar in front of the hub...not physically where the handlebar is to the hub by plum bobing. BTW...for those roadies out there this convention is analogous to being in the drops and having the handlebar cover the hub...flatbar a bit farther forward than dropbar because of sweep 'back' versus dramatic forward sweep and then hook position back toward the rider with dropbar.

    That said...how tall are you and do you have long arms and legs? I ride with 24.5" EFF top tube + 120mm stem with 10 deg rise. I am 6'1" with long arms and legs.
    Cheers.

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    The whole handlebar/hub/line of sight thing is complete crap and isn't based on anything other than pure coincidence. (Just like KOPS is total junk for finding saddle fore/aft). Weight distribution and balance is key when setting up your cockpit. Two people with the same inseam/torso length can have VERY different setups depending on their body type. Someone with more upper body mass shouldn't necessarily have the same reach as a skinnier person.

    There's no free lunch when it comes to fit and trying to dial it in over the internet is really just wasting your time. Everything is a trade off and a compromise. You just have to see what works best for you and your riding conditions. Going to a local fit expert is a good start.... but reach and bar height are largely personal preferences and is something that you will need to work on yourself.

    I'm always amazed at how changing my bar height 5-10mm can have drastic effects on the ride. It can mean the difference between bombing a downhill section or riding timid. I often use slightly different bar heights for different trails/race courses. Flatter, more tight and twisty, then I lower them to get more weight on the front wheel. If there is more climbing and descending, then the bars come up. I don't lose anything on the climbs and am MUCH fast on the descents.... again with only a small change in bar height.

  5. #5
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    Quote Originally Posted by briscoelab
    The whole handlebar/hub/line of sight thing is complete crap and isn't based on anything other than pure coincidence. (Just like KOPS is total junk for finding saddle fore/aft). Weight distribution and balance is key when setting up your cockpit. Two people with the same inseam/torso length can have VERY different setups depending on their body type. Someone with more upper body mass shouldn't necessarily have the same reach as a skinnier person.

    There's no free lunch when it comes to fit and trying to dial it in over the internet is really just wasting your time. Everything is a trade off and a compromise. You just have to see what works best for you and your riding conditions. Going to a local fit expert is a good start.... but reach and bar height are largely personal preferences and is something that you will need to work on yourself.

    I'm always amazed at how changing my bar height 5-10mm can have drastic effects on the ride. It can mean the difference between bombing a downhill section or riding timid. I often use slightly different bar heights for different trails/race courses. Flatter, more tight and twisty, then I lower them to get more weight on the front wheel. If there is more climbing and descending, then the bars come up. I don't lose anything on the climbs and am MUCH fast on the descents.... again with only a small change in bar height.
    I figured this would beg a philosophical debate about the 'merit' of conventions and so your response was predictable. You are in large measure correct but...conventions are like stereotypes. Are they always true? No...for the reasons you explained...statistical outliars in particular due to body proportion. Is there a reason that conventions come into being? Yes.
    We can debate KOPS till the cows come home. If you look at fit from a statistical standpoint, more than not have average femur to tibia length ratios and KOPS works for a great many as a 'general' guideline or convention. I fit most of the conventions closely and I have been racing road bikes for 30 years. Your last comments are spot on. A top rider can feel 2mm in cockpit change. I know I can. 5-10mm is indeed huge and transformative in terms of that sense of feeling dialed in.
    Thanks for your comments.
    PS: I ride behind KOPS on both road and off road and my bars cover my hub on my road bike.

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    Quote Originally Posted by dirtrider7
    I don't know Coach...I think you missed how the convention works. It is 'line of sight' from rider on the bike seeing the handlebar in front of the hub...not physically where the handlebar is to the hub by plum bobing. BTW...for those roadies out there this convention is analogous to being in the drops and having the handlebar cover the hub...flatbar a bit farther forward than dropbar because of sweep 'back' versus dramatic forward sweep and then hook position back toward the rider with dropbar.

    That said...how tall are you and do you have long arms and legs? I ride with 24.5" EFF top tube + 120mm stem with 10 deg rise. I am 6'1" with long arms and legs.
    Cheers.
    That is one of the most ambiguous fit methods ever, even on the road.

    By rounding or straightening my back (all within a "normal" posture) I can "move" the bar well forward or far behind the hub. Even more when I use my elbows.

    The forearm reach is better, but not much.

    At best, these may get you into a range of fit than can work, then you can fine tune it, and to compare a new bike to a fit you know that works for you.
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  7. #7
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    Instead of always wondering if you got a good fit, go ahead and drop the $200 and get measured and fit from a Wobble Naught fit guy. It's a lot of money, yes, but then for the rest of your life you'll have your exact body measurements, your bike fit, and will be able to move it from bike to bike (as long as the seat tube angle is similar, if not you'll need to adjust the fit slightly)

    I ended up getting 2 fits. One on my SF100 and one on my Fuel. The seat tube angle was vastly different (5 degrees) between the two. Now that I have those two bikes measured and know the fit, I was easily able to transfer the fit to my road bike, and when my SS gets here, I'll be able to easily do that as well.

    -Tom

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    Quote Originally Posted by trhoppe
    Instead of always wondering if you got a good fit, go ahead and drop the $200 and get measured and fit from a Wobble Naught fit guy. It's a lot of money, yes, but then for the rest of your life you'll have your exact body measurements, your bike fit, and will be able to move it from bike to bike (as long as the seat tube angle is similar, if not you'll need to adjust the fit slightly)

    I ended up getting 2 fits. One on my SF100 and one on my Fuel. The seat tube angle was vastly different (5 degrees) between the two. Now that I have those two bikes measured and know the fit, I was easily able to transfer the fit to my road bike, and when my SS gets here, I'll be able to easily do that as well.

    -Tom
    Hi Tom,
    Having a Wobble Naught Fit is not neccessarily the best fit for each rider either. No doubt it is money well spent for many riders however. The great Eddie Merckx constantly evolved his fit 1mm at a time...having hundreds of custom frames built. Later in his career he chased pain and was always looking for that magic equation of different fit parameters that would allow him to ride fastest without pain. It wouldn't have worked for him
    I can do the trig from bike to bike so no problem there.
    Cheers.

  9. #9
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    So far responses have been...conventions suck and get a fit.

    If you care to, I would like to hear how you guys fit on your bike...
    - Handlebar relative to Hub from line of sight on the bike
    - Elbow to middle finger distance relative to stem

    Lets see if these conventions are baloney or comport with how many here ride.
    Thanks.

  10. #10
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    Quote Originally Posted by trhoppe
    Instead of always wondering if you got a good fit, go ahead and drop the $200 and get measured and fit from a Wobble Naught fit guy. It's a lot of money, yes, but then for the rest of your life you'll have your exact body measurements, your bike fit, and will be able to move it from bike to bike (as long as the seat tube angle is similar, if not you'll need to adjust the fit slightly)

    I ended up getting 2 fits. One on my SF100 and one on my Fuel. The seat tube angle was vastly different (5 degrees) between the two. Now that I have those two bikes measured and know the fit, I was easily able to transfer the fit to my road bike, and when my SS gets here, I'll be able to easily do that as well.

    -Tom
    If you base the fit measurements off of the BB it transfers to all frames (though not necessarily riding style). The frames' reach and stack is more accurate for fitting than the STA or ETT.

    Super Fly 100, 19": STA 73.6; ETT 61.7cm; frame reach 43.3cm
    Fuel EX, 18.5": STA 72.5; ETT 60.9; reach 42.8
    Top Fuel, 18.5": STA 73.5; ETT 60.5; reach 43.7
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  11. #11
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    Quote Originally Posted by dirtrider7
    So far responses have been...conventions suck and get a fit.

    If you care to, I would like to hear how you guys fit on your bike...
    - Handlebar relative to Hub from line of sight on the bike
    - Elbow to middle finger distance relative to stem

    Lets see if these conventions are baloney or comport with how many here ride.
    Thanks.
    I have posted this link about fit many times before. Originally about designing a new frame, but the same method works for transferring fit to a new frame or checking to see if a frame can be setup to fit. I should update it to include "reach" (horizontal distance from BB to top of head tube) and "stack" (vertical distance from BB to top of head tube).
    http://forums.mtbr.com/showpost.php?...6&postcount=13
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  12. #12
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    While I am sure some members will disagree...

    getting a professional fit from a reputable shop is great. While you can get things dialed in fairly well solo, it never hurts (pun intended) to get a second opinion from a respected fit specialist.

    This is especially true imo if you are prone to IT band issues etc...

    Top pro racers get fitted. They spend more time on a bike than any of us.

  13. #13
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    Quote Originally Posted by rydbyk
    getting a professional fit from a reputable shop is great. While you can get things dialed in fairly well solo, it never hurts (pun intended) to get a second opinion from a respected fit specialist.

    This is especially true imo if you are prone to IT band issues etc...

    Top pro racers get fitted. They spend more time on a bike than any of us.
    As long as you understand proper fit is still an opinion once you are in the general range. Go to 5 different fitters an you are likely to get 5 different fits.
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  14. #14
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    My Wobble Naught fit experience was very good. Well worth the time and money.
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    Cool diagram Shiggy. I'd be interested in a post concerning the percieved/accepted advantages/disadvantages of the variety of factors that influence fit/preformance--aside from frame size and degree angles. A search would be hard to pull off in order to look into all of the following factors:
    Handlebar width, rise, and sweep.
    Stem length and rise.
    Seatpost setback.
    Crankarm length.

    I will do some searching, but if anyone knows of a post/thread that covers these areas well will you please link it here?

  16. #16
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    Quote Originally Posted by shiggy
    As long as you understand proper fit is still an opinion once you are in the general range. Go to 5 different fitters an you are likely to get 5 different fits.

    Sure. Also one needs to consider their limitations. Getting into that acceptable range is the starting point.

  17. #17
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    Quote Originally Posted by bluestatevirgin
    Cool diagram Shiggy. I'd be interested in a post concerning the percieved/accepted advantages/disadvantages of the variety of factors that influence fit/preformance--aside from frame size and degree angles. A search would be hard to pull off in order to look into all of the following factors:
    Handlebar width, rise, and sweep.
    Stem length and rise.
    Seatpost setback.
    Crankarm length.

    I will do some searching, but if anyone knows of a post/thread that covers these areas well will you please link it here?
    The hard part is getting the fit in the first place. There are constant discussions on fit/position for different riding styles.

    All of those factors fit into my measuring method to achieve the same fit/position/balance.
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  18. #18
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    Dude, you need to stop reading MB Fiction. I saw that article the other day and couldn't beleieve what a load of horse shite it was, absolute and utter to be precise. That BS about your forarm from saddle to middle of stem is BS to the highest degree, my fingers just barely reach the back of the stem and loads (including yourself I believe) have said I look upright on my bikes.

    Fit is something that you learn over time with trying different approaches and ideas, only then can you really have an idea or understanding as to how different changes effect fit. I've been riding MTBs now for 7 years and I know exactly how I like my bikes, I know the upper and lower limits of what cockpit I can ride and what angles I like. You can gain more knowledge on here if you filter it right than from a lot of the "pro" fitters.
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    Quote Originally Posted by LyNx
    Dude, you need to stop reading MB Fiction. I saw that article the other day and couldn't beleieve what a load of horse shite it was, absolute and utter to be precise. That BS about your forarm from saddle to middle of stem is BS to the highest degree, my fingers just barely reach the back of the stem and loads (including yourself I believe) have said I look upright on my bikes.

    Fit is something that you learn over time with trying different approaches and ideas, only then can you really have an idea or understanding as to how different changes effect fit. I've been riding MTBs now for 7 years and I know exactly how I like my bikes, I know the upper and lower limits of what cockpit I can ride and what angles I like. You can gain more knowledge on here if you filter it right than from a lot of the "pro" fitters.
    Now that you mention it, the guy in those pics needs to bend his elbows and looks a bit cramped for an XC/trail position.
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  20. #20
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    Quote Originally Posted by LyNx
    Dude, you need to stop reading MB Fiction. I saw that article the other day and couldn't beleieve what a load of horse shite it was, absolute and utter to be precise. That BS about your forarm from saddle to middle of stem is BS to the highest degree, my fingers just barely reach the back of the stem and loads (including yourself I believe) have said I look upright on my bikes.

    Fit is something that you learn over time with trying different approaches and ideas, only then can you really have an idea or understanding as to how different changes effect fit. I've been riding MTBs now for 7 years and I know exactly how I like my bikes, I know the upper and lower limits of what cockpit I can ride and what angles I like. You can gain more knowledge on here if you filter it right than from a lot of the "pro" fitters.
    You are too upright The guy shown is in a good position. You didn't factor in the second and equally important component of fit...drop. Reach and hence torso angle is an equal function of both horizontal and vertical legs of the triangle.
    Most have missed the point of the thread. Maybe you got it because at least you answered the question about elbow to stem...but didn't answer the other question...nor has anybody else. Of course fit is variable. Below is another picture of rider and his bike. He is on a relatively small bike relative to his size. This can be accomplished with a substantial drop which is typically a function of bigger rider on a medium sized bike. Some like a big drop with bars a bit closer in which has the same net reach as higher bars farther away. The difference then becomes upper arm angle relative to the torso. It has been speculated that the best position is with upper arm at a 90 deg angle to the torso and torso angle at approx 45 degrees to vertical. Both riders shown have this position.
    Attached Thumbnails Attached Thumbnails Dialing in Riding Position-attackposition.jpg  

    Dialing in Riding Position-3-inch-drop.jpg  


  21. #21
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    Quote Originally Posted by dirtrider7
    You are too upright The guy shown is in a good position. You didn't factor in the second and equally important component of fit...drop. Reach and hence torso angle is an equal function of both horizontal and vertical legs of the triangle.
    Most have missed the point of the thread. Maybe you got it because at least you answered the question about elbow to stem...but didn't answer the other question...nor has anybody else. Of course fit is variable. Below is another picture of rider and his bike. He is on a relatively small bike relative to his size. This can be accomplished with a substantial drop which is typically a function of bigger rider on a medium sized bike. Some like a big drop with bars a bit closer in which has the same net reach as higher bars farther away. The difference then becomes upper arm angle relative to the torso. It has been speculated that the best position is with upper arm at a 90 deg angle to the torso and torso angle at approx 45 degrees to vertical. Both riders shown have this position.
    And for what I look for in a decent fit, both riders do not have enough bend in their elbows. To hit the points you are talking about they have to have nearly straight arms.
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  22. #22
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    Quote Originally Posted by shiggy
    And for what I look for in a decent fit, both riders do not have enough bend in their elbows. To hit the points you are talking about they have to have nearly straight arms.
    We can debate whether the arm position is too straight. I believe its mostly camera angle...they have elbow flex, just not extreme. Further, shown are static positions. Both riders can easily bend their elbows more from this position and ride more leaned over.
    For me, its about finding the sweet spot with bar height. Many believe riding more upright with higher bars will be more comfortable when the converse is true. When riding most of us seek a natural torso angle to enlist our glutes into the pedal stroke. If the handlebar is too high, this will create too much compression in the arms telegraphing to shoulders, neck and traps creating soreness. That's what I like about both positions shown. The bars are low enough such that they don't push back on the rider when riding fast.

  23. #23
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    One of the simplest things I can think to tell anyone is when you make changes to the bike, make them one at a time. Don't change the handlebar height and the seat height and the fore-aft on the seat and ride it. Make each adjustment and feel it out for a ride.
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    Well that there is THE BEST bit of advice given in this thread or that could be given by any pro fitter I'll only add...give the adjustment some time before you decide it's not working before you move on to doing other adjustments.

    Quote Originally Posted by NYrr496
    One of the simplest things I can think to tell anyone is when you make changes to the bike, make them one at a time. Don't change the handlebar height and the seat height and the fore-aft on the seat and ride it. Make each adjustment and feel it out for a ride.
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    You're doing mtbr wrong, you're supposed to get increasingly offended by the implications that you're doing ANYTHING wrong.

  25. #25
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    Well IMO "professional bike fit" is a waste of time.
    I have paid for 3 seperate bike fits from highly recommended fitters and have been unable to ride any of them for much more than a few rides before changing them all back.
    The last "professional" fit I had did not even last a ride.
    The fit that has worked best for me has been an online one I did which has now worked for me for a few years.
    One fitter told me I could not possibly fit on the bike I had. What he meant was I could not fit on the bike in the way he wanted to fit me with my saddle an extra inch higher than I was riding it.
    IMO, find a position that you are comfortable with and leave it alone. Professional bike fitters have no formal qualifications and are simply following some "rules" that their fit system (Specialized, Bikefit, Wobblenaught etc) gives them. For the most part they have no idea about your spinal alignment or any other medical issues that you may have.
    The other thing with fit that I think is overlooked is your ability to comfortably ride. By this I mean are you suffering pain in your back, knees, hips, shoulders etc. If so then get these things looked at and fixed. I have ridden with pain for a while now and this is why I had pursued the fits. I have now gone the opposite direction. I have left my fit alone and am seeing a chiropractor who has sorted out much of my back and hip issues. A few more visits and I think that these issues will be gone.

  26. #26
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    Quote Originally Posted by dirtrider7
    I know there are a lot of accomplished XC riders on here...much more than me....and I would like to tap into your thoughts on best riding position. Most don't become good riders by accident and they are vigilant about fit and set up. I also know...this is highly subjective and really a choice more than a formula. I would like to focus on XC and higher speed riding position if possible recognizing that DH is many times more upright. I have searched for general rules of thumb when it comes to best set up and have come a way with a couple of conventions. Yes, we all know how flawed conventions are and not universally applicable but here a couple:

    - When seated and looking down on a mtb, the handlebar should be out in front of the front hub by 1 inch or so.

    - Place your elbow against the nose of the saddle and your middle forefinger should end up between the steerer centerline and stem clamp center.

    According to both I am riding a bit stretched out and wondered about you guys? My handlebar is about 1.5-2" in front of my hub and my middle forefinger only extends about an inch past the steerer centerline...and I have longish arms.

    The complexity of fit relates to the elusive balance between horizontal reach and vertical drop...each collectively make up reach...i.e. distance from shoulder joint to handlebar. In my case, the top of my handlebar with sag is about even to the top of saddle. No doubt running more drop than this would require I reposition my handlebar closer to satisfy my net reach.

    Anyway, I wanted to see how close these conventions satisfy your fit? I am tempted to experiment with a shorter stem and a bit more drop to have my hands a bit closer to my body and more underneath my torso versus a more 'hammock' position of higher bars farther away and stretched out.

    Please let me know what you think.
    As usual, the conventions do not apply to me (I'm happy to say ).

    I am 6'-3", 34" pants, normal arms, rigid bike, bars (~635mm ProMoto 5 deg. flat) are ~2" below the seat, and I ride pretty much everything except gap jumps.

    My middle finger can reach the front edge of my top cap.
    Does that mean my top tube is too long? MCR9, Lg. = 24.5 ETT
    ...or is my seat too short? ...or is it back too far on the rails?
    My hams, quads, glutes, back, and shoulders say "no".

    My front axle lines up right behind my handlebar.
    Does that mean my stem is too short? It is 90mm, down from 120mm (which would have put it about an inch in front of my axle by line of sight, but my lats were taking a beating having to stretch that far - it came off my 26er).
    ...or is my seat too far forward? ...or is my HT angle wrong? ...or do I need less fork offset?

    If I am in a "cornering" position/posture, my handlebar, by line of sight, is 6" behind the front axle (I am low and forward, weighting the front end).

    If I am in a "descending" posture/position, the bar is 6" in front of the axle (I am low and back - just floating the front tire lightly over the ground).

    Even if I was in a static position like road riding and didn't even need the ability to juke and jive on the bike, I can't see where those conventions would apply unless I had a funky geometry bike or the wrong size bike.

    All that to say that the convention does not suit me.

    -F

    PS - I think that convention might be from the early '90's.
    PPS - the guy in your picture needs bigger wheels.
    (and his seat looks too high)

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    I used Competitive Cyclist's Fit Calculator. I'm a really goofy sized dude and it came up with a comfy ride for me. Try it out:

    http://www.competitivecyclist.com/za...LCULATOR_INTRO

  28. #28
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    ive been trained to fit. the training was JUNK.
    the main stuff ive picked up over the last 17yrs of mtb is as follows:
    starting with seat height put your pedal at 6 o'clock. with your heel on the axle of the pedal your knee should be pretty much straight.
    placing the ball of your foot on the axle of the pedal you should be able to JUST barely drop your heel to straighten your leg.
    dont let your knees come up high enough to squish the pbj out of your your stomach
    at the top of your pedal stroke (this is important for your stem length)
    ride for a bit and slide the seat to where you dont feel like you are falling off the back or the front with the stem you are riding.
    THEN if you feel like you have room to go down towards the front wheel without regurgitating, lengthen the stem to where
    your elbows have a SLIGHT bend to them and your shoulders are square. you may have to move your saddle fore or aft again.
    no reaching for the bars. line of sight is bs on a mtb.
    a wider bar with a short stem is better for DH and jumping over stuff. that configuration uses more back muscles and is better for yanking the front wheel off the ground and fast "rearward weighted" decents.
    a shoulder width bar plus MAYBE a couple inches keeps your steering quick is key for a killer xc setup.

    one of the things i notice is how a TON of folks dont get their brake levers and shifters fit
    to their hands. if your levers are too high you tend to ride with your wrists down behind the bars.
    start with your levers almost UNDER the bar and rotate them forward till they are in line with your forearms and just come into your grasp
    with a straight forearm.

    fit is fudging over time and its different for everyone. comfort is key.
    play with your bike, dont pay for someone to drop a plumb bob from your knee.
    Last edited by dubtrialsin; 05-05-2011 at 09:49 PM.
    "my cat's breath smells like catfood."
    -ralph wiggum

  29. #29
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    Quote Originally Posted by Fleas
    As usual, the conventions do not apply to me (I'm happy to say ).

    I am 6'-3", 34" pants, normal arms, rigid bike, bars (~635mm ProMoto 5 deg. flat) are ~2" below the seat, and I ride pretty much everything except gap jumps.

    My middle finger can reach the front edge of my top cap.
    Does that mean my top tube is too long? MCR9, Lg. = 24.5 ETT
    ...or is my seat too short? ...or is it back too far on the rails?
    My hams, quads, glutes, back, and shoulders say "no".

    My front axle lines up right behind my handlebar.
    Does that mean my stem is too short? It is 90mm, down from 120mm (which would have put it about an inch in front of my axle by line of sight, but my lats were taking a beating having to stretch that far - it came off my 26er).
    ...or is my seat too far forward? ...or is my HT angle wrong? ...or do I need less fork offset?

    If I am in a "cornering" position/posture, my handlebar, by line of sight, is 6" behind the front axle (I am low and forward, weighting the front end).

    If I am in a "descending" posture/position, the bar is 6" in front of the axle (I am low and back - just floating the front tire lightly over the ground).

    Even if I was in a static position like road riding and didn't even need the ability to juke and jive on the bike, I can't see where those conventions would apply unless I had a funky geometry bike or the wrong size bike.

    All that to say that the convention does not suit me.

    -F

    PS - I think that convention might be from the early '90's.
    PPS - the guy in your picture needs bigger wheels.
    (and his seat looks too high)
    Thanks for answering the questions. You are quite right, those conventions don't work for you. Seems pretty universal that most of us don't have our middle finger moving up the stem with elbow against the nose of the saddle. I don't either...but I run a fair amount of setback because of my long femurs to keep my CG back.
    I will say I would feel crowded with your postion of bars 'behind' the axle. I too am tall with long arms so our proportions aren't that different likely.
    Cheers.

  30. #30
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    Quote Originally Posted by elsewhere
    ive been trained to fit. the training was JUNK.
    the main stuff ive picked up over the last 17yrs of mtb is as follows:
    starting with seat height put your pedal at 6 o'clock. with your heel on the axle of the pedal your knee should be pretty much straight.
    placing the ball of your foot on the axle of the pedal you should be able to JUST barely drop your heel to straighten your leg.
    dont let your knees come up high enough to squish the pbj out of your your stomach
    at the top of your pedal stroke (this is important for your stem length)
    ride for a bit and slide the seat to where you dont feel like you are falling off the back or the front with the stem you are riding.
    THEN if you feel like you have room to go down towards the front wheel without regurgitating, lengthen the stem to where
    your elbows have a SLIGHT bend to them and your shoulders are square. you may have to move your saddle fore or aft again.
    no reaching for the bars. line of sight is bs on a mtb.
    a wider bar with a short stem is better for DH and jumping over stuff. that configuration uses more back muscles and is better for yanking the front wheel off the ground and fast "rearward weighted" decents.
    a shoulder width bar plus MAYBE a couple inches keeps your steering quick is key for a killer xc setup.

    one of the things i notice is how a TON of folks dont get their brake levers and shifters fit
    to their hands. if your levers are too high you tend to ride with your wrists down behind the bars.
    start with your levers almost UNDER the bar and rotate them forward till they are in line with your forearms and just come into your grasp
    with a straight forearm.

    fit is fudging over time and its different for everyone. comfort is key.
    play with your bike, dont pay for someone to drop a plumb bob from your knee.
    Unless you are being overly simplistic, I am surprised with your background by your response. You seemed to be more focused on position of saddle relative to the handlebars versus where most fitters start...establishing fore/aft position of the saddle relative to the BB which affects balance on the bike and ultimately weight on the hands that many object to with a lower handlebar. Is KOPS imperfect for determining absolute fore/aft position...yes but a quick measurement of femur and tibia will explain if its a decent metric or not relative to rider CG.
    In any event, thanks for your response.

  31. #31
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    i was kinda putting stuff into pretty simple terms..
    getting your body into a postion where you can fall asleep (not from going numb) is most important (as close to 50/50 over the bb)
    leg extension and shoulder arc are critical after that.
    some folks who have a longer torso will have to move the saddle rearward/ viceversa
    ive always started with height before reach, if you drop a body onto a frame and allow it to
    relax in a neutral/ balanced/ standing postion, the saddle should be slid to meet the right zone as well as the stem changed to meet the palms.
    the amt of weight on your arse can be pretty pre-determined by the frame geo/ type of riding the bike was intended for as well..
    interfaces are so personal to every individual that a fit cannot be done in one session.
    its hard to do over the web, and most folks will take stuff to such extremes that it gets rediculous.
    im sure ive let some incomplete thoughts fall here on this page due to some serious
    adhd and caffine along with lack of sleep, but the gist is all focused on comfort and balance without numbness.
    sorry if i caused confusion...
    "my cat's breath smells like catfood."
    -ralph wiggum

  32. #32
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    oh and JUNK maybe wasnt the right word...
    maybe more common sense stuff that could be a duh for an ol'schooler..
    there are some bits that everyone can benefit from, but there is no law in fit.
    "my cat's breath smells like catfood."
    -ralph wiggum

  33. #33
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    Quote Originally Posted by dirtrider7
    Thanks for answering the questions. You are quite right, those conventions don't work for you. Seems pretty universal that most of us don't have our middle finger moving up the stem with elbow against the nose of the saddle. I don't either...but I run a fair amount of setback because of my long femurs to keep my CG back.
    I will say I would feel crowded with your postion of bars 'behind' the axle. I too am tall with long arms so our proportions aren't that different likely.
    Cheers.
    If you ride rigid I think it helps to have a slightly shorter cockpit so that your front suspension (arms) can follow the terrain even as you steer and shift your weight. If you're stretched out, it limits the length of your suspension travel, or it puts a little too much weight forward (for me).

    For the sake of proportion, I think most peoples' arm span equals their height.

    -F

  34. #34
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    Quote Originally Posted by elsewhere
    i was kinda putting stuff into pretty simple terms..
    getting your body into a postion where you can fall asleep (not from going numb) is most important (as close to 50/50 over the bb)
    leg extension and shoulder arc are critical after that.
    some folks who have a longer torso will have to move the saddle rearward/ viceversa
    ive always started with height before reach, if you drop a body onto a frame and allow it to
    relax in a neutral/ balanced/ standing postion, the saddle should be slid to meet the right zone as well as the stem changed to meet the palms.
    the amt of weight on your arse can be pretty pre-determined by the frame geo/ type of riding the bike was intended for as well..
    interfaces are so personal to every individual that a fit cannot be done in one session.
    its hard to do over the web, and most folks will take stuff to such extremes that it gets rediculous.
    im sure ive let some incomplete thoughts fall here on this page due to some serious
    adhd and caffine along with lack of sleep, but the gist is all focused on comfort and balance without numbness.
    sorry if i caused confusion...
    I appreciate your comments. My sense reading what you wrote is fittting isn't done necessarily by tape measure alone...but rather the dynamic picture created by watching a rider on a trainer with a skilled eye. The body/frame interface is too complex to have a cook book recipe.
    I will tell you flexibility is big. I have been riding for 40 years and was out riding my road bike aggressively for 30 miles with my buddies yesterday late afternoon. I am lacking good base miles this year because of crappy weather. I rebuilt my bike over the winter and decided to slam the position with about a 3 inch drop. I am paying for it today big time...very sore neck and back. My typical position is about 1.5 inch drop on my road bike which you know is very pedestrian. Reality is I am not young though still reasonably fast but can't ride in an aggressive position in particular this early in the season without paying the consequences.
    Cheers.

  35. #35
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    Quote Originally Posted by shiggy
    If you base the fit measurements off of the BB it transfers to all frames (though not necessarily riding style). The frames' reach and stack is more accurate for fitting than the STA or ETT.

    Super Fly 100, 19": STA 73.6; ETT 61.7cm; frame reach 43.3cm
    Fuel EX, 18.5": STA 72.5; ETT 60.9; reach 42.8
    Top Fuel, 18.5": STA 73.5; ETT 60.5; reach 43.7
    You see that's what I thought too. And it works for hardtail bikes, but not full suspension bikes. You're forgetting about suspension sag and what that does to the angles of the bike. The seat tube angle, head tube angle, and other bike relationships are totally different when the suspension is compressed with sag. The SF100 suspension type for example makes for a lot steeper of a set tube angle when at sag then the Fuel EX does. The Fuel EX seat takes a slight angle deflection etc. You don't want to do your fit/measure static to static on a FS bike. You have to be dynamic

    -Tom

  36. #36
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    One thing I found opposite of what was said in the first post is reach versus bar height. If the bars are lower then more reach actually seems to work better, and higher bars seem to work better with less reach. It seems counterintuitive, but that is my experience.

    Back when I was XC racing in the early-90's, the trend was having the bars significantly below the saddle height, like 4"+, and using very long stems -- around 130mm. Now most racers don't have a position that agressive. I used to ride with that agressive, low, stretched-out position, but now I prefer the bars to be just a little below the saddle (about 1-2"). I have also experimented with different stem lengths, and I always seem to get the most balanced handling with a 100mm stem.

  37. #37
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    Quote Originally Posted by jabrabu
    One thing I found opposite of what was said in the first post is reach versus bar height. If the bars are lower then more reach actually seems to work better, and higher bars seem to work better with less reach. It seems counterintuitive, but that is my experience.

    Back when I was XC racing in the early-90's, the trend was having the bars significantly below the saddle height, like 4"+, and using very long stems -- around 130mm. Now most racers don't have a position that agressive. I used to ride with that agressive, low, stretched-out position, but now I prefer the bars to be just a little below the saddle (about 1-2"). I have also experimented with different stem lengths, and I always seem to get the most balanced handling with a 100mm stem.
    I'm struggling w/ fit right now. Coming from a 26" mtb with about a 3" drop and a 120mm stem. The cockpit on my 29er is about 1.5" shorter than what i'm used to. I miss the more aggressive riding position, but it was always sketchy on the descents. Playing w/ the fit, but i'm going to try a 110mm stem and go from a 9 deg to a 10 deg (both flipped). Trying to strike a happy balance between being "laid out" and in a good position for bombing the downhills.

  38. #38
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    Hello,

    I've been wanting to check out my setup and found this on the web, after searching through different youtube videos and other sites. Welcome to BikeFittingKit.com

    Has anyone tried this kit? Is there another kit or site that works better, or should i say, more people agree to a better ride after setup?

    Thanks,

    Gripshift
    What am I going to do with forty subscriptions to Vibe?

  39. #39
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    I base all my fit off the bb position in relation to my hip placement and this has served me well since working with that cycling coachwhen i was 13,im 38 now and can till turn pedals all day uphill down hill ect.keep in mind that was road bike fit that was translated to my then ridgid 1989 ibis.btw im just a mountain biker,not trail dh am fr xc or any other title although i do have a carbon ht a short travelxc bike and an am bike as well as a cx and road.all have the tip of the seat roughly 1.75"behind the bb measured via plumb bob i then set my reach and bar height based on how much weight in on my hands or how much weight i need on the front end.in short i own tons of cheapo stems and bars to get my fit set the way i need

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