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Discussion Starter · #1 ·
I have recently changed my stem fron a 9cm to an 11 as I was too bunched up. I know I have the right frame and saddle height but can anyone advise on weather its a good idea to shift the saddle even further forward and lengthen the stem further to get more over the pedals which I prefer to be... thus shifting the correct length set up a cm more? what are the disadvantages of moving futher forward in riding position? I am mainly a climber but also love riding in the drops stretched out on the flats. any comments much appreciated...
 

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You should set the saddle where you want it, then adjust the stem length to suit.

The rule of thumb is to set the fore-aft position so your knee is over the forward pedal spindle (KOPS) with the pedals level. Use a plumb bob (a large nut tied to a string works). Depending on who you read, you either measure from the very front of the knee, or from the bony protuberance right under the knee cap, which results in a slightly more forward position. But KOPS is just a rule of thumb starting point and there is a some disagreement about it. See for example "the myth of KOPS" by Keith Bontrager.

My experience is that moving back involves your hamstrings and butt more, moving forward uses your quads more. So if your hamstrings and butt are tired after a hard ride and your quads are still fresh, move the saddle forward a bit.

Don't forget that when you slide your saddle forward you are (with most seat posts) also lowering it.
 

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Discussion Starter · #3 ·
ericm979 said:
You should set the saddle where you want it, then adjust the stem length to suit.

The rule of thumb is to set the fore-aft position so your knee is over the forward pedal spindle (KOPS) with the pedals level. Use a plumb bob (a large nut tied to a string works). Depending on who you read, you either measure from the very front of the knee, or from the bony protuberance right under the knee cap, which results in a slightly more forward position. But KOPS is just a rule of thumb starting point and there is a some disagreement about it. See for example "the myth of KOPS" by Keith Bontrager.

My experience is that moving back involves your hamstrings and butt more, moving forward uses your quads more. So if your hamstrings and butt are tired after a hard ride and your quads are still fresh, move the saddle forward a bit.

Don't forget that when you slide your saddle forward you are (with most seat posts) also lowering it.
Thanks a lot for the advice.. much apprec... I'll certainly try this..
 

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see www.cyclingnews.com answers by Steve Hogg

henry said:
Thanks a lot for the advice.. much apprec... I'll certainly try this..
Search www.cyclingnews.com web site for Steve Hogg's numerous answers on thes topic of saddle for/aft position, saddle height and stem lengths and many other topics. Similar to Keith Bontrager, Steve Hogg thinks KOPS is largely coincidental and most (road/racing) riders need to be somewhat behind KOPS, anywhere from 5mm behind and up to 25mm behind in fact, and some even more.
 

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Hi Henry
The KOPS gives a good start point, as described above, but like all things to do with bike positioning, it's all down to your body. I have what sounds like a similar issue - to me, my Gunnar with its 73.5 degree seat angle is a "real laid back" bike - short thighs will do it to you any day!

What I could suggest is that you only change one thing at a time and only by a small, measured amount - and give yourself decent riding time to feel out the change.

I'd also suggest you measure up your position so you can track what changes you make - you can download a positioning chart off Park Tools website that makes this job easy.

There's a spin-off from maintaining that positioning chart - if you ever decide to move your saddle up or down a little, undo the bolt and the seatpost drops right down into your seat tube :eek: , the time taken to record your saddle height suddenly will seem really worth-while!

Go figure how I can strongly suggest that one :D

Hope that helps

Dereck
 

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For/Aft position is about.......

balance over the bike, nothing more.

KOPS is coincidental.

depending on where your weight is (Heavier in the torso compared to the but/legs or vice versa.....will dictate your for aft position. Thinkabout it with the example Keith gives in his article (The myth of KOPS)....when you bend over from the waist from a standing position, notice that you counteralance your torso leaning forward by sticking your Butt out in the opposite direction. this is natural.

In an extreme, if you move your position too far forward, all of your weight will beon you hands....not a good thing over a long ride.

What you want is to end up in a position where 55% or so of your weight is on the rear wheel and 45% on the front wheel. (you can check this with a bathroom scale with some helpfrom a friend) If you are balanced.....there is little if any hand discomfort.

Len
 

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Second Dereck's advice on keeping measurements, I forgot to include that.

I put a turn of electrical tape around the seatpost so its lower edge just touches the frame when the seatpost
is in the correct position. That way if I remove the post I can put it back in exactly right. It also provides a visual indicator if the seat post is slipping down in the frame.

Saddle should be positioned for best biomechanical operation (power/comfort), not weight distribution on the bike. I personally think it is bunk-- weight distribution is important for handling in some forms of motorsports where race performance is determined by handling. In cycling its all about the engine (your legs) and in osme events, bike handling skills (your brain). The bike's actual handling characteristics are pretty immaterial.
But if you are concerned with weight distribution, you should set that with your stem and top tube length after optimizing the saddle position.
 

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Sorry...but you are wrong...

ericm979 said:
Saddle should be positioned for best biomechanical operation (power/comfort), not weight distribution on the bike. I personally think it is bunk-- weight distribution is important for handling in some forms of motorsports where race performance is determined by handling. In cycling its all about the engine (your legs) and in osme events, bike handling skills (your brain). The bike's actual handling characteristics are pretty immaterial.
But if you are concerned with weight distribution, you should set that with your stem and top tube length after optimizing the saddle position.
Weight distribution translates into comfort and therefor performance over long rides....and as to your contention that weight distribution doesn't affect handling....you are flat out wrong....that is unless you are talking about slow speeds......shift your seat all the way back on the rails and then reduce the stem proportionately....then take it down a winding descent...see how you like the handling....then reverse it.(If you survive)....and slam the seat all the way forward and put an ultra long stem on....do the same descent......finally do the descent with your current setup...if you don't notice a dramatic difference in handling you are either dead or insensitive as all hell.

Actual Bike handling immaterial....BWhaaaaaaaaaaaaaaa

Thanks for the Laugh.

Len
 

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73.5 is not laid back.......

Dereck said:
Hi Henry
The KOPS gives a good start point, as described above, but like all things to do with bike positioning, it's all down to your body. I have what sounds like a similar issue - to me, my Gunnar with its 73.5 degree seat angle is a "real laid back" bike - short thighs will do it to you any day!

What I could suggest is that you only change one thing at a time and only by a small, measured amount - and give yourself decent riding time to feel out the change.

I'd also suggest you measure up your position so you can track what changes you make - you can download a positioning chart off Park Tools website that makes this job easy.

There's a spin-off from maintaining that positioning chart - if you ever decide to move your saddle up or down a little, undo the bolt and the seatpost drops right down into your seat tube :eek: , the time taken to record your saddle height suddenly will seem really worth-while!

Go figure how I can strongly suggest that one :D

Hope that helps

Dereck
it is actually relativly steep......(Unless you are on a tiny frame......Most bikes are 73.0.....Laid back STA's are usually in the 72's

Good advice on the positioning chart

Len
 

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Len J said:
balance over the bike, nothing more.

KOPS is coincidental.

depending on where your weight is (Heavier in the torso compared to the but/legs or vice versa.....will dictate your for aft position. Thinkabout it with the example Keith gives in his article (The myth of KOPS)....when you bend over from the waist from a standing position, notice that you counteralance your torso leaning forward by sticking your Butt out in the opposite direction. this is natural.

In an extreme, if you move your position too far forward, all of your weight will beon you hands....not a good thing over a long ride.

What you want is to end up in a position where 55% or so of your weight is on the rear wheel and 45% on the front wheel. (you can check this with a bathroom scale with some helpfrom a friend) If you are balanced.....there is little if any hand discomfort.

Len
This is interesting Len. I always looked at saddle fore/aft positioning as matter of muscle recruitment (hamstring/glutes v quads as described above) not weight balance. But your point makes sense to me. I know you own a Serotta, is this something you got from their fit philosophy as well or is this all Bontrager?
 

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It's actually about both......

Sintesi said:
This is interesting Len. I always looked at saddle fore/aft positioning as matter of muscle recruitment (hamstring/glutes v quads as described above) not weight balance. But your point makes sense to me. I know you own a Serotta, is this something you got from their fit philosophy as well or is this all Bontrager?
muscle recruitment and weight distribution/comfort......position is always about balance.

No, I got it from a combination of fitting, Bontager, and playing around with my position......try exagerating the movements fore & aft (Using dramatically different length stems) on your bike and see how it affects handling and comfort.....the differences are immense.

I like figiting and thinking things out......the further back your seat is, the less weight on your hands......stands to reason that it affects weight balance......change weight balance and you have to change the bike handling. The interesting part to me is once you find the right weight balance for your body and fitness......then you can find the right bike. Me, I need a slack seat tube &/Or setback seatpost to get my seat in the right position.

If I was a racer, I might give up some comfort to get more weight forward, or use a shorter TT/longer stem to get more weight forward for speed handling.

Len
 

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Too far forward = BAD

henry said:
I have recently changed my stem fron a 9cm to an 11 as I was too bunched up. I know I have the right frame and saddle height but can anyone advise on weather its a good idea to shift the saddle even further forward and lengthen the stem further to get more over the pedals which I prefer to be... thus shifting the correct length set up a cm more? what are the disadvantages of moving futher forward in riding position? I am mainly a climber but also love riding in the drops stretched out on the flats. any comments much appreciated...
The bad thing is that over time, (if you don't follow the KOPS line of thinking) with your knees slightly forward of the pedal axle, you do run a risk of having some knee problems. I found that I had an occasional knee tenderness after some longer rides. My knee was slightly forward of the pedal, moving my saddle back 2 mm was all that I needed to correct this problem.
 
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