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  1. #1
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    Bike fit question

    Long story short, Im disproportional with long legs and short torso. 5'11 with nearly 34" inseam. My height also makes me a tweener between M and L frames. I had a M Krampus that required 40mm of saddle setback to reach comfortable knee over pedal position. Question is, will going to a L frame improve my position forward considering the seat tube angle is the same? Thanks

  2. #2
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    No, you will just have less seat post showing.
    I got some bad ideas in my head.

  3. #3
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    Fit should start with reach ,that starts with top tube length.

  4. #4
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    I'm 5'9" with a 34" bike inseam and am pretty average, I think. How are you measuring yours?
    Do the math.

  5. #5
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    I am 6 foot and 34.4 cycling inseam so very similar. I always ride a large---no way a medium and with some bikes an XL-------but most often a large on Specialized---Pivot---Yeti---Giant----- But say on a trek I am xl.

    My biggest fit issue is I like reach of 460---I find bikes 475 and up not the best for me---but with new geo I need the sitting top tube (ETT) to be a bit longer than many larges-see lots of bikes with less than 630 ETT and I like about 635--so I tend to push the seat back and that gets too much weight on the back wheel. This is a common issue with long legged and short torso folks.

  6. #6
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    Quote Originally Posted by bryanmac View Post
    Long story short, Im disproportional with long legs and short torso. 5'11 with nearly 34" inseam. My height also makes me a tweener between M and L frames. I had a M Krampus that required 40mm of saddle setback to reach comfortable knee over pedal position. Question is, will going to a L frame improve my position forward considering the seat tube angle is the same? Thanks
    5'11 with a 33.5" inseam is the top of the bell curve. You're a completely average man. You should not be considering mediums. KOPS is happy coincidence nonsense. It could mean your saddle is too high/low, you're not on an upright or steep bike, or that you're right in the region where you can adjust things with impunity. Meaningless. Emblematic of absurd 90s roadie dogma we should consciously ignore.


    There are some people who are gonna strike out on their own and outfit a bike with 2" of riser stem and/or 2" of saddle setback. Either decision ruins the handling of any good mtb. They're the cyclist equivalent of hypochondriacs, to their own disservice. If that's not you, get a large and get it outfitted comfortably with the stock build, then after 200 miles consider buying a couple aftermarket cockpit components to get it that last 3%. If you're moving anything more than 15mm be aware you're making a massive change if you bought a quality/well fitted bike. Take advantage of the fact that every Large production frame is tailor made for you.
    Last edited by scottzg; 12-12-2018 at 01:51 AM.
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  7. #7
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    I'm 6'0" with nearly 36" bike inseam. Looong legs, short waist. A large frame with spacers and riser bars to get the grips to saddle level works for me. XL frames have too much TTL.

    If you're dealing with a shop, just try the model you want in both sizes. Start with getting the reach right, then the rest can be tweaked one way or another.
    Use it, use it, use it while you still have it.

  8. #8
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    Knee-over-pedal-spindle is bunk. Go read Keith Bontrager's commentary on the subject.

    oddly enough, I paid for a professional fit and the fitter put my cleats all the way forward, on my AM hardtail, and dropped a plumb line from my knee and called it good. I was riding on my tip-toes like that for less than four miles before I got off the bike and put my cleats back in a rational position. I have since switched to flats anyhow, but the point is that "professional" expert bike fitters are still stuck in old myths about how a bike should fit.

    fit should start with reach. then look at saddle position. it sounds like you would benefit from a bike with a longer reach or a slack-er seat tube angle.

  9. #9
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    Appreciate the responses. By disproportional, I forgot to mention longer femurs. I have been professionally fit on tri and road bikes in the past but now doing 400 mile mostly offload bike pack races on plus tire mtn bikes. Im accepting that having a comfortable upright position for technical terrain then slid back where I need to be on saddle in aero position on bars is not possible. Ya, weird mix, I know!! lol.. Luckily I rarely have knee issues anymore and minimal body issues for 16hr back to back days pushing a 55lb bike, but we are always looking for that "perfect" position that I guess doesn't exist! Thanks again everyone!!

  10. #10
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    I'm 5'8 and usually on the medium side of the M/L equation (though for Santa Cruz, larges fit better).

    I'd also bet that larges would fit you better overall, maybe with a slightly shorter stem if your torso is on the small side of a large.

    Your long femurs might mean tweaking crank length would make more sense (such as, using slightly longer cranks than others might choose). Of course that introduces other compromises, but that comes to my next point.

    Any out-of-the-ordinary dimensions throw kinks into fitting "stock" bikes. There comes a point if you want a "perfect" fit, that you may not be able to achieve it with a stock bike if you have any odd dimensions, and you might have to go custom to pull it off with the fewest compromises elsewhere.

    Here's an "odd fit" example. I have longish arms for my height, which turns out to be a good problem to have for mountain biking (big range of motion when I'm standing on the pedals and want to throw the bike around in tech terrain). But my wife has short arms, which makes mtb fitting difficult, particularly ensuring she has "space" to move her body in technical terrain, since your arm length plays a role in your possible range of movement. It took us years of fiddling with a few different bikes before she found what actually worked for her. I wouldn't say that what she has now is perfect, but it's better than anything she's had previously. As a result, the handling of her bike feels more natural to her, which helps her on-the-bike confidence a lot.

    I was getting dangerously close to recommending she go for a full custom frame until she found her current bike (and found it to work well). She would have seriously balked at the cost, but I was starting to narrow down the sorts of frame dimensions she needed to at least try, and was seeing how few options she had for stock bikes. We made a several-hundred mile spontaneous weekend trip so she could demo one.

  11. #11
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    Quote Originally Posted by bryanmac View Post
    Appreciate the responses. By disproportional, I forgot to mention longer femurs. I have been professionally fit on tri and road bikes in the past but now doing 400 mile mostly offload bike pack races on plus tire mtn bikes. Im accepting that having a comfortable upright position for technical terrain then slid back where I need to be on saddle in aero position on bars is not possible. Ya, weird mix, I know!! lol.. Luckily I rarely have knee issues anymore and minimal body issues for 16hr back to back days pushing a 55lb bike, but we are always looking for that "perfect" position that I guess doesn't exist! Thanks again everyone!!
    Long femurs' relationship to seat angle is also mostly bunk. Your knees are further down, but their relationship to the pedals doesn't really change. I used to have a graphic to illustrate it, but i can't find it.

    edit- found it
    Name:  DdMWZhz.jpg
Views: 161
Size:  21.0 KB

    A slacker seat position for grinding away in the saddle with a loaded bike makes sense all by itself, and sizing down to preserve your reach when you slam the saddle back also makes sense. More sensible to find a frame intended for that style of riding, i think (geometry intended for slack sta), but your original question makes a lot more sense now.

    As for plus bikes designed around a slacker seat angle... jones makes one. I don't know of any more off the top of my head because plus bikes and steep seat angles 'arrived' at the same time.

    Someone will know! Good luck with the hunt!
    "Things that are complex are not useful, Things that are useful are simple."
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  12. #12
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    I should of added more details up front. I didn't expect to get so many detailed and knowledgeable responses... Ya, the style of riding I do and geo I'm looking for really is niche so its understandable that there aren't many bikes that fit that mold. But is becoming more popular. Im currently on a niner ROS 9 plus that has the biocentric BB that can make minor geo fit changes by rotating. Im just looking for more relaxed and purpose built frame. And possibly Ti. Yes, jones and surly ECR are pretty much the only 29plus built exactly for my application as well as the muru mungo Ti which I am probably going to end up with. Unfortunately, because of reasons above, are pretty rare and nearly impossible to test ride. The search continues...

  13. #13
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    Quote Originally Posted by bryanmac View Post
    I should of added more details up front. I didn't expect to get so many detailed and knowledgeable responses... Ya, the style of riding I do and geo I'm looking for really is niche so its understandable that there aren't many bikes that fit that mold. But is becoming more popular. Im currently on a niner ROS 9 plus that has the biocentric BB that can make minor geo fit changes by rotating. Im just looking for more relaxed and purpose built frame. And possibly Ti. Yes, jones and surly ECR are pretty much the only 29plus built exactly for my application as well as the muru mungo Ti which I am probably going to end up with. Unfortunately, because of reasons above, are pretty rare and nearly impossible to test ride. The search continues...
    I'd go custom steel if you're looking at ti frame price point. The cost is similar and you can get exactly what you want. Your application is really unusual and 30lbs of gear strapped to the bike really changes things up.

    ...the muru mungo looks pretty sweet.
    "Things that are complex are not useful, Things that are useful are simple."
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  14. #14
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    man I am the opposite....5'11 with 30 inseam

  15. #15
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    I kind of think KOPS is a useful way to get a neutral set up for a novice rider. Itís a starting point. I kind of think preference in bike fit have as much to do with how a rider develops their power and how flexible they are as it does with body proportions. Power and flexibility shape riding techniques.
    MERCY! MERCY! MERCY!

  16. #16
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    Quote Originally Posted by MOJO K View Post
    I kind of think preference in bike fit have as much to do with how a rider develops their power and how flexible they are as it does with body proportions. Power and flexibility shape riding techniques.
    Do you have any input as to how the OP can go about adopting a more typical saddle position? 40mm post offset on a Krampus is extreme IMO. I also have long femurs and a short torso, and rode for years with lots of saddle offset (i.e. slack effective STA), typically riding SS to avoid seated climbs. Am I condemned to how I developed my power + my bodily proportions? My attempts to slowly migrate the saddle forward have invariably resulted in knee pain and loss of power, and a retreat to a more rearward position. I'm glad to be free of knee pain, but would like to fit the modern geo better.
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