Long Legs Short Torso - Fit KOPS

[photogy]

I have a very tough time sizing a bike. I have had two in the last two years that appear to be a fit problem and would like to find the right size once and for all.

Currently I ride a Lemond Reno 59cm frame. I have a long femur and stand six feet overall. I have a short trunk however. What I find is that in order to get the proper seat tube length, I end up with 1.5 inches (about 4cm) short of KOPS with the saddle rails all of the way forward. I think this means that I have a short thigh. I also feel that I stretch to the handle bars even after shortening the stem and installing bars with a little less forward loop. I tend to push back rather that pulling them as well.I have always been slow and wonder is being 4cm behind the spindle is the cause.

I see that Profile Design has a carbon seatpost that can get me about 4cm forward, but that is with the seat rails fully forward as well.

I like the feel of frames with the angled top tube, but perhaps this is the problem. Can anyone advise me?

 

[alfeng]

I have a very tough time sizing a bike. I have had two in the last two years that appear to be a fit problem and would like to find the right size once and for all.

Currently I ride a Lemond Reno 59cm frame. I have a long femur and stand six feet overall. I have a short trunk however. What I find is that in order to get the proper seat tube length, I end up with 1.5 inches (about 4cm) short of KOPS with the saddle rails all of the way forward. I think this means that I have a short thigh. I also feel that I stretch to the handle bars even after shortening the stem and installing bars with a little less forward loop. I tend to push back rather that pulling them as well.I have always been slow and wonder is being 4cm behind the spindle is the cause.

I see that Profile Design has a carbon seatpost that can get me about 4cm forward, but that is with the seat rails fully forward as well.

I like the feel of frames with the angled top tube, but perhaps this is the problem. Can anyone advise me?

Okay, to be politically incorrect, let me begin by saying that different ethnic groups -- AND, even different people within those ethnic groups -- have different bone structures & body/muscle types ... so, trying to fit what may have been the ideal riding position for Eddie Merckx may not be feasible for you, or me.

However, what I think only has so much weight ... but, I think that you can take heart in the observation which Keith Bontrager (you know, the name behind all of those BONTRAGER labeled products used by TREK & sister brands):

http://www.sheldonbrown.com/kops.html​

BTW. You can't have both a long femur and a short thigh ...

Bontrager's article assured ME that my deduction that NOT following the KOPS positioning was more-than-okay.

BTW2. It is probably better (heck, best) to fit-the-frame you ride based on the top tube length ... some adjustements ARE made based on the seattube & headtube angles by way of the stem & saddle position. What is the length of your torso between the chair (firm) and your shoulder BONE when seated & sitting up straight? What is the length of your arm between the shoulder BONE & the crook between your thumb & index finger?

How in-/flexible are you, generally? Can you bend over & touch the ground without bending your knees? Do you want a "commuting" position OR a "touring" position OR a "racing" position on the bike?

 

[vascdoc]

I have a very tough time sizing a bike. I have had two in the last two years that appear to be a fit problem and would like to find the right size once and for all.

Currently I ride a Lemond Reno 59cm frame. I have a long femur and stand six feet overall. I have a short trunk however. What I find is that in order to get the proper seat tube length, I end up with 1.5 inches (about 4cm) short of KOPS with the saddle rails all of the way forward. I think this means that I have a short thigh. I also feel that I stretch to the handle bars even after shortening the stem and installing bars with a little less forward loop. I tend to push back rather that pulling them as well.I have always been slow and wonder is being 4cm behind the spindle is the cause.

I see that Profile Design has a carbon seatpost that can get me about 4cm forward, but that is with the seat rails fully forward as well.

I like the feel of frames with the angled top tube, but perhaps this is the problem. Can anyone advise me?

Lemond typically have a long top tube. A proper fit in terms of the frame is important. You can tune the fits within a small window but being in the proper ballpark is most important. The frame comes first then dial it in using the stem and seatpost, etc. Just my 2 cents.

 

[Camilo]

I have a very tough time sizing a bike. I have had two in the last two years that appear to be a fit problem and would like to find the right size once and for all.

Currently I ride a Lemond Reno 59cm frame. I have a long femur and stand six feet overall. I have a short trunk however. What I find is that in order to get the proper seat tube length, I end up with 1.5 inches (about 4cm) short of KOPS with the saddle rails all of the way forward. I think this means that I have a short thigh. I also feel that I stretch to the handle bars even after shortening the stem and installing bars with a little less forward loop. I tend to push back rather that pulling them as well.I have always been slow and wonder is being 4cm behind the spindle is the cause.

I see that Profile Design has a carbon seatpost that can get me about 4cm forward, but that is with the seat rails fully forward as well.

I like the feel of frames with the angled top tube, but perhaps this is the problem. Can anyone advise me?

Have you worked with experienced people at a bike shop? That would be my first suggestion. I do caution you to use some skepticism when dealing with local bike ship personnel. In my experience, some are excellent, but many (most?) have no more knowledge than standover height and some other arbitrary benchmarks when it comes to fitting.

Just off hand, I'd also suggest that you look at the geometry of your Lemond and then compare to some other bikes. It sounds roughly that you need a bike that has a shorter top tube relative to the seat tube. But, again, there is no substitute for and experienced bike person to look at you, look at your current bike, and make a recommendation for adjustment or changing frames.

There are a couple of fitting websites that seem to make sense. I don't necessarily think you can just take their calculations as gospel, but you can certainly learn a lot (especially how it compares to your current bike - which is a known quantity and known deficiencies). The two I know of are www.wrenchscience.com and www. competativecyclist.com.

Good luck.

 

[photogy]

Okay, to be politically incorrect, let me begin by saying that different ethnic groups -- AND, even different people within those ethnic groups -- have different bone structures & body/muscle types ... so, trying to fit what may have been the ideal riding position for Eddie Merckx may not be feasible for you, or me.

However, what I think only has so much weight ... but, I think that you can take heart in the observation which Keith Bontrager (you know, the name behind all of those BONTRAGER labeled products used by TREK & sister brands):

http://www.sheldonbrown.com/kops.html​

BTW. You can't have both a long femur and a short thigh ...

Bontrager's article assured ME that my deduction that NOT following the KOPS positioning was more-than-okay.

BTW2. It is probably better (heck, best) to fit-the-frame you ride based on the top tube length ... some adjustements ARE made based on the seattube & headtube angles by way of the stem & saddle position. What is the length of your torso between the chair (firm) and your shoulder BONE when seated & sitting up straight? What is the length of your arm between the shoulder BONE & the crook between your thumb & index finger?

How in-/flexible are you, generally? Can you bend over & touch the ground without bending your knees? Do you want a "commuting" position OR a "touring" position OR a "racing" position on the bike?

Thanks,

I have read Bontrager's areticle however it appears that I am more efficient in the KOPS position. I have tested this on my bike by enduring the pain that comes with sliding forward on the saddle to approximate the correct postion, and I find that my speed increases, I am using more of my muscles with less stress and my pedal stroke improves. The problem with testing it in this manner is that sliding forward just that much makes the farvorite part of my anatomy kind of unhappy! I also have a better reach and controll of the bars.

As for flexibility, I am 46 years old (young). I stretch the back of my legs with a standing crossover and can touch the tips of my shoes. Not great, but not bad either. I would like to spend time in the drops, but the hoods are where I am most of the time.

I need to re-measure all of those body parts, but I did it some time ago on Competitive Cyclist's site and was rather surprised that they reccomended some measurements that were longer than I currently ride at.

 

[photogy]

Have you worked with experienced people at a bike shop? That would be my first suggestion. I do caution you to use some skepticism when dealing with local bike ship personnel. In my experience, some are excellent, but many (most?) have no more knowledge than standover height and some other arbitrary benchmarks when it comes to fitting.

Just off hand, I'd also suggest that you look at the geometry of your Lemond and then compare to some other bikes. It sounds roughly that you need a bike that has a shorter top tube relative to the seat tube. But, again, there is no substitute for and experienced bike person to look at you, look at your current bike, and make a recommendation for adjustment or changing frames.

There are a couple of fitting websites that seem to make sense. I don't necessarily think you can just take their calculations as gospel, but you can certainly learn a lot (especially how it compares to your current bike - which is a known quantity and known deficiencies). The two I know of are www.wrenchscience.com and www. competativecyclist.com.

Good luck.

As for LBS, I agree that the knowlege level is apalling. There is one shop in town that is excellent, however, his inventory is weighted heavely toward steel frames. He reccomended a more traditional geomentry, and he did not carry any such items. He reccomended that I look specificly at Lemond (which he does not cary) and that is how I ended up with my current ride. I like the feel of the bike under me in motion, better than an old Diamondback steel frame that I have with strictly traditional geomentry that I bought back in 1994 (BTW I have almost the exact same problem with my Diamondback. Just about 4cm short of KOPS).

The manufacturers available locally (in lower mid range bikes) are prety limited; Trek, Lemond, Specialized, Giant etc.), and mostly compact type frames. Of course there are many of the very expensive models avialable.

Trust is a huge issue here. I really don't know what I have until I have ridden a bike for several hours with pedals etc.

Ulimately, I need to decide weather putting the Profile Design carbon forwad setting seatpost will solve the problem and come to grips with the fact that if I do that, I will be at the very edge of the bikes ability to accomidate me or trash my current ride and travel to a larger city to sample what is available.

Thanks for all of your advice!

 

[matagi]

I have a very tough time sizing a bike. I have had two in the last two years that appear to be a fit problem and would like to find the right size once and for all.

Currently I ride a Lemond Reno 59cm frame. I have a long femur and stand six feet overall. I have a short trunk however. What I find is that inorder to get the proper seat tube length, I end up with 1.5 inches (about 4cm) short of KOPS with the saddle rails all of the way forward. I think this means that I have a short thigh. I also feel that I stretch to the handle bars even after shortening the stem and installing bars with a little less forward loop. I tend to push back rather that pulling them as well.I have always been slow and wonder is being 4cm behind the spindle is the cause.

I see that Profile Design has a carbon seatpost that can get me about 4cm forward, but that is with the seat rails fully forward as well.

I like the feel of frames with the angled top tube, but perhaps this is the problem. Can anyone advise me?

Sorry to be pedantic, but you cannot have a long femur and a short thigh. You can have tight muscles, which affect your flexibility but femur length and thigh length are rather inextricably linked.

Also, KOPS is just a guide to initial positioning and set-up, it is not the Holy Grail of bike set-up.

If you are pushing back on the bars it sounds like your current set-up is in fact too short. You may need to take the plunge and travel to a larger centre to find someone who specialises in bike fit. You may also find that the only way you will get a comfortable fit is to go for a custom frame.

 

[bobbyOCR]

That is unlucky. A long femur will mean you will need to be further behind the BB, and a short torso means you would have to choose a bikes size appropriate for your reach, not your inseam. Which again means you will probably need a massive stack of spacers to make your bar-saddle drop realistic.

Try a 56cm next time. But some measurements would be nice.

 

[oldbobcat]

Try a 56cm next time. But some measurements would be nice.

Next time you buy a bike take a tape measure and compare. And read the frame geometry tables on the manufacturers' web sites.

 

[photogy]

That is unlucky. A long femur will mean you will need to be further behind the BB, and a short torso means you would have to choose a bikes size appropriate for your reach, not your inseam. Which again means you will probably need a massive stack of spacers to make your bar-saddle drop realistic.

Try a 56cm next time. But some measurements would be nice.

OK, well I have:

Inseam 91cm
Arm Lenght 63.5 CM
Sternal Notch to Floor 150CM

All of the above is dependent on the measuirment instructions however. Arm lenght is from bump on shoulder to wrist bone.

 

[oldbobcat]

Wow, I just looked up the dimensions of the Reno. The 59 has a virtual top tube length of 59.1. You'd be a lot more comfortable somewhere between 57 and 58 cm. LeMond designed his frames long because that's the way Cyrille Guimard fit Gitanes to the Renault-Elf team in the 80s. It works find if you happen to have Greg's proportions and you don't mind sitting on a bike like a mid-80s racer. Guimard liked long cranks and big gears, too, an idea that helped bung up Bernard Hinault's knees.

Eddie Merckx was about six feet and lanky. He and the other Belgian riders of the 70s started the lower, flat-backed position that is now carried to the extreme by today's pro riders. The 58.5 cm (C-C) DeRosas Eddie rode in the 70s had 57 cm top tubes, 175 cm cranks, and 13 cm Cinelli quill stems. You might be able to use this as a starting point to getting properly set up.

 

[alfeng]

OK, well I have:

Inseam 91cm
Arm Lenght 63.5 CM
Sternal Notch to Floor 150CM

All of the above is dependent on the measuirment instructions however. Arm lenght is from bump on shoulder to wrist bone.

Okay, the above numbers just don't make sense ...

If you are 6' tall, that's the same as 83cm, so your sternal notch to the floor cannot be 150cm!

You need a new tape measure ...

At this point, sight-unseen, I would recommendd that you fit the frame solely on your torso length ... whatever top tube length is suitable for a shorter person of "normal" proportions with the same torso size (which you don't state) ... use an appropriately long seat post & deep drop (low bar position ... probably, minimal spacers) to get your back (and, head) in a suitable riding position.

Good luck!

 

[davedbk]

If you are 6' tall, that's the same as 83cm

You missed the one on the front alfeng. (6X12X2.54 = 182.9cm)

 

[alfeng]

You missed the one on the front alfeng. (6X12X2.54 = 182.9cm)

YES!

Thanks for the correction & sorry for my error!

 

[bing181]

OK, well I have:

Inseam 91cm
Arm Lenght 63.5 CM
Sternal Notch to Floor 150CM

Pretty similar to me ... height 183, inseam 89, st. notch 149, not sure how you measured your arm.

I've been professionally setup, though it's pretty close to the online fitting at competitivecyclist.com, maybe look there. I basically run a 57 x 57 (c-c) with 110 cm stem .. I would have thought a 59 Lemond would be one or two sizes to big. There are plenty of bikes around that off the shelf have a shorter TT - I have both Colnago and Merckx bikes, and both fit well to what I need without any radical adaption.

As for KOPS .. it's a starting point and a guideline. Try it and see, but equally try forward/back (especially back) a little and see.

B