How does power change with saddle set-back?
08-27-17, 11:25 PM
#1
Senior Member
Thread Starter
How does power change with saddle set-back?
I've been playing around with saddle set-back in an attempt to get more comfortable (on my sit-bones) and to find a good balance point to avoid putting too much weight on my arms and pressure on my shoulders.
I ended up with a quite a lot of set-back - about 10cm from the bottom bracket to the tip of the saddle (a Fizik Antares), which does tend to make it feel as though I am "pushing the pedal from the rear" rather than pressing down on top of it.
I'm about 3-4cm behind KOPS.
I often find I end up pedalling slightly "heel-down", which can cause some lower leg strain if I don't watch out for this. I've also had a bit of foot numbness, but don't know if the set-back is the cause, or whether this is due to cleat angle or simply having my shoes done up too tight!
In terms of power output (and muscle usage) how does this vary with saddle set-back, and is there an optimal position for an individual? More importantly, could this optimal position be different to the optimal "balance point", requiring a compromise position to be found?
I've recently tried using a longer stem with a lower angle (I was using a 30 degree riser stem before), because I was feeling a bit cramped in the cockpit, and felt I need to get into a lower position that allowed my arms to "drape" over the bars more easily. I have found that this position stretches me out noticeably more (it's increases reach by 37mm compared to the riser stem), and that my seated position on the saddle has come forward naturally by a little bit.
Given my saddle set-back was already quite large, should I move the saddle forward to compensate, so that my sit bones align to the widest part of the saddle as before? Am I likely to undo all my work finding a good balance point to keep weight of my hands if I do this?
It seems every time I try to fine tune my position for comfort by changing one thing, I end up affecting a lot more parameters!
I ended up with a quite a lot of set-back - about 10cm from the bottom bracket to the tip of the saddle (a Fizik Antares), which does tend to make it feel as though I am "pushing the pedal from the rear" rather than pressing down on top of it.
I'm about 3-4cm behind KOPS.
I often find I end up pedalling slightly "heel-down", which can cause some lower leg strain if I don't watch out for this. I've also had a bit of foot numbness, but don't know if the set-back is the cause, or whether this is due to cleat angle or simply having my shoes done up too tight!
In terms of power output (and muscle usage) how does this vary with saddle set-back, and is there an optimal position for an individual? More importantly, could this optimal position be different to the optimal "balance point", requiring a compromise position to be found?
I've recently tried using a longer stem with a lower angle (I was using a 30 degree riser stem before), because I was feeling a bit cramped in the cockpit, and felt I need to get into a lower position that allowed my arms to "drape" over the bars more easily. I have found that this position stretches me out noticeably more (it's increases reach by 37mm compared to the riser stem), and that my seated position on the saddle has come forward naturally by a little bit.
Given my saddle set-back was already quite large, should I move the saddle forward to compensate, so that my sit bones align to the widest part of the saddle as before? Am I likely to undo all my work finding a good balance point to keep weight of my hands if I do this?
It seems every time I try to fine tune my position for comfort by changing one thing, I end up affecting a lot more parameters!
Last edited by johngwheeler; 08-28-17 at 04:01 PM.
08-28-17, 12:17 AM
#2
Senior Member
How long have you been riding?
For myself, finding the most efficient position took a few years of trial and error. There aren't any specific rules, only loose guidelines when it comes to fit vs comfort.
Seat position relative to bar position varies over time. As you ride, particularly if you ride in the drops, your back is able to flatten out, without tilting your pelvis forward. Nowadays the top of my bar is about 5cm lower than the nose of my saddle, and I am flexible enough to ride resting my forearms on the top of the bar. When I started riding road bikes, the bar was higher, and I wasn't at all flexible enough to ride with my arms on the bar.
If you start losing a lot of weight (as I did), comfort improves because your arms and butt are supporting less weight.
When racing in Europe, a coach there made two small recommendations to my setup; to move my seat a little more to the rear, and to tilt the nose up just few millimeters. At first the new position felt uncomfortable, but it made a noticeable improvement in my climbing.
Fit and comfort take a long time to get right. You can't really get it perfect, but you can get pretty close. Adjustments should be made one at a time, and you need to give yourself time to get used to them to see if they really make a difference. Don't adjust more than one thing at once, as one kind of adjustment can negate the effect of another adjustment.
For myself, finding the most efficient position took a few years of trial and error. There aren't any specific rules, only loose guidelines when it comes to fit vs comfort.
Seat position relative to bar position varies over time. As you ride, particularly if you ride in the drops, your back is able to flatten out, without tilting your pelvis forward. Nowadays the top of my bar is about 5cm lower than the nose of my saddle, and I am flexible enough to ride resting my forearms on the top of the bar. When I started riding road bikes, the bar was higher, and I wasn't at all flexible enough to ride with my arms on the bar.
If you start losing a lot of weight (as I did), comfort improves because your arms and butt are supporting less weight.
When racing in Europe, a coach there made two small recommendations to my setup; to move my seat a little more to the rear, and to tilt the nose up just few millimeters. At first the new position felt uncomfortable, but it made a noticeable improvement in my climbing.
Fit and comfort take a long time to get right. You can't really get it perfect, but you can get pretty close. Adjustments should be made one at a time, and you need to give yourself time to get used to them to see if they really make a difference. Don't adjust more than one thing at once, as one kind of adjustment can negate the effect of another adjustment.
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08-28-17, 05:38 AM
#3
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I've been playing around with saddle set-back in an attempt to get more comfortable (on my sit-bones) and to find a good balance point to avoid putting too much weight on my arms and pressure on my shoulders.
I ended up with a quite a lot of set-back - about 10cm from the bottom bracket to the tip of the saddle (a Fizik Antares), which does tend to make it feel as though I am "pushing the pedal from the rear" rather than pressing down on top of it.
I'm about 3-4cm behind KOPS.
I often find I end up pedalling slightly "heel-down", which can cause some lower leg strain if I don't watch out for this. I've also has a bit of foot numbness, but don't know if the set-back is to cause, or whether this due to cleat angle or simply having my shoes done up too tight!
I ended up with a quite a lot of set-back - about 10cm from the bottom bracket to the tip of the saddle (a Fizik Antares), which does tend to make it feel as though I am "pushing the pedal from the rear" rather than pressing down on top of it.
I'm about 3-4cm behind KOPS.
I often find I end up pedalling slightly "heel-down", which can cause some lower leg strain if I don't watch out for this. I've also has a bit of foot numbness, but don't know if the set-back is to cause, or whether this due to cleat angle or simply having my shoes done up too tight!
08-28-17, 07:19 AM
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You've had so many fit threads where you're changing your contact points willy-nilly - at this point, I'd talk to a few fitters, to find one that you're comfortable working with, for a fitting and follow-up after a certain number of miles.
08-28-17, 07:41 AM
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How saddle setback by itself affects power who can say - probably doesn't. But if you look at time trial setups, they like the saddle much more forward and tilted down, though you do tend to put more weight on your hands that way.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
08-28-17, 08:29 AM
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OP...fit is a work in progress. I have ridden in just about every position excepting mega drop like a TdF rider.
Pro's...not to extrapolate too closely even run over 100mm setback saddle nose to BB center...for some taller riders like Boonen. Some the same size ride less setback. More setback thwarts ability to ride aero because of constraining hip angle...why TT riders ride forward and doesn't hurt their speed. But as you say, there is more pressure on hands in a more forward position. TT riders hold up their almost horizontal torso with elbows...not core as with a road bike. But a data point about speed can be derived.
My personal belief is 'power' versus speed is more a function of hip angle which isn't dramatically different between road bike and TT bike as it turns out. Close the hip angle too much, and less leverage/power...but and big but....a more closed position is still generally faster because reduction in power is less than improvement in aerodynamics. Aero rules the day when riding over 20 mph on a road bike in terms of watt expenditure.
You maybe interested in this for reference:
Here is a chart for setback from B.Hinault's book and was used by all of Guimard's riders(Hinault, LeMond and Fignon). Measurement is from tip of the saddle nose to center of BB measured horizontally.
Cycling Inseam versus Saddle Setback
75 to 78cm. 4 to 6cm.
79 to 82cm. 5 to 7cm.
83 to 86cm. 6 to 8cm.
87 to 90cm. 7 to 9cm.
I think above is decent rule of thumb but as with many conventions, certainly not set in stone.
Further and not to put too much stock in pro riders, the trend has moved a bit toward less setback and even nose down saddle position based upon some relenting of the UCI. Keep in mind however, pros put out a lot higher average wattage which naturally unweighs the torso...so careful about adopting a pro position unless blessed with great flexibility and strong legs.
Pro's...not to extrapolate too closely even run over 100mm setback saddle nose to BB center...for some taller riders like Boonen. Some the same size ride less setback. More setback thwarts ability to ride aero because of constraining hip angle...why TT riders ride forward and doesn't hurt their speed. But as you say, there is more pressure on hands in a more forward position. TT riders hold up their almost horizontal torso with elbows...not core as with a road bike. But a data point about speed can be derived.
My personal belief is 'power' versus speed is more a function of hip angle which isn't dramatically different between road bike and TT bike as it turns out. Close the hip angle too much, and less leverage/power...but and big but....a more closed position is still generally faster because reduction in power is less than improvement in aerodynamics. Aero rules the day when riding over 20 mph on a road bike in terms of watt expenditure.
You maybe interested in this for reference:
Here is a chart for setback from B.Hinault's book and was used by all of Guimard's riders(Hinault, LeMond and Fignon). Measurement is from tip of the saddle nose to center of BB measured horizontally.
Cycling Inseam versus Saddle Setback
75 to 78cm. 4 to 6cm.
79 to 82cm. 5 to 7cm.
83 to 86cm. 6 to 8cm.
87 to 90cm. 7 to 9cm.
I think above is decent rule of thumb but as with many conventions, certainly not set in stone.
Further and not to put too much stock in pro riders, the trend has moved a bit toward less setback and even nose down saddle position based upon some relenting of the UCI. Keep in mind however, pros put out a lot higher average wattage which naturally unweighs the torso...so careful about adopting a pro position unless blessed with great flexibility and strong legs.
Last edited by Campag4life; 08-28-17 at 08:33 AM.
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08-28-17, 08:46 AM
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There are positions and pedaling techniques that provide more power.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
08-28-17, 08:54 AM
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There are positions and pedaling techniques that provide more power.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
Your last point Doge, shouldn't be overlooked. Pretty much 'all' riders can generate more power with a more open hip angle including TT riders. So it always comes down to hip angle versus power versus speed. The power versus speed part of the equation shouldn't be overlooked. That is why optimizing power isn't necessarily the formula to optimizing speed. Optimizing speed is more about a more closed hip angle and slamming the torso to the top tube which typically is not the maximum power position. Sliding to the rear of the saddle, closes the hip angle and thwarts ability to rotate torso more parallel to the top tube...why TT riders ride in the opposite saddle forward position.
Last edited by Campag4life; 08-28-17 at 08:58 AM.
08-28-17, 09:09 AM
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There are positions and pedaling techniques that provide more power.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
But they also come at another cost, like higher HR/less efficient, shorter duration etc.
The other part is the muscle development of the rider. The balance between lower back, glutes, quads etc affect what position may product more power. So it depends.
For me...
Sliding back on the seat and being more upright I can produce more short term power. My legs are straighter and I bring in more lower back.
Just to add because its a nuanced point that is many times not understood....
Your last point Doge, shouldn't be overlooked. Pretty much 'all' riders can generate more power with a more open hip angle including TT riders. So it always comes down to hip angle versus power versus speed. The power versus speed part of the equation shouldn't be overlooked. That is why optimizing power isn't necessarily the formula to optimizing speed. Optimizing speed is more about a more closed hip angle and slamming the torso to the top tube which typically is not the maximum power position. Sliding to the rear of the saddle, closes the hip angle and thwarts ability to rotate torso more parallel to the top tube...why TT riders ride in the opposite saddle forward position.
Your last point Doge, shouldn't be overlooked. Pretty much 'all' riders can generate more power with a more open hip angle including TT riders. So it always comes down to hip angle versus power versus speed. The power versus speed part of the equation shouldn't be overlooked. That is why optimizing power isn't necessarily the formula to optimizing speed. Optimizing speed is more about a more closed hip angle and slamming the torso to the top tube which typically is not the maximum power position. Sliding to the rear of the saddle, closes the hip angle and thwarts ability to rotate torso more parallel to the top tube...why TT riders ride in the opposite saddle forward position.
08-28-17, 09:23 AM
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I am talking power as measured by a power meter at the hub, not speed.
For an anaerobic/sprint opening hip/straighter leg seems to always offer more power. But even sprinters are near that 90 degree hip angle at max power. Some sprinters do more power with lower bar than a higher one. I see it close to the same position where someone is moving the big weight on a leg press.
But when it comes to aerobic / longer power I'm not convinced the same position is best. The limiting factor for mid-range power is still aerobic (whole system - HR, lungs, O2 uptake, waste disposal, not just VO2 max). So I think any muscle groups could be developed to deliver. It is more than just being aero/or not. I have seen more 20min power developed in riders that train for it, in a more closed position. If spending may hours, days, months on the TT position I see that long term power as good as being more upright. This can be seen in TT specialists and some Tri riders that spend all the time riding this way. The body and power changes.
On hills many produce more power on a hill than on the flat. I expect that is due to opening up hip angle, and with that a lower cadence. But some will do similar longer time power in a TT position with more closed angle in higher cadence. So I'm not convinced how important the position is for those that train in it.
For an anaerobic/sprint opening hip/straighter leg seems to always offer more power. But even sprinters are near that 90 degree hip angle at max power. Some sprinters do more power with lower bar than a higher one. I see it close to the same position where someone is moving the big weight on a leg press.
But when it comes to aerobic / longer power I'm not convinced the same position is best. The limiting factor for mid-range power is still aerobic (whole system - HR, lungs, O2 uptake, waste disposal, not just VO2 max). So I think any muscle groups could be developed to deliver. It is more than just being aero/or not. I have seen more 20min power developed in riders that train for it, in a more closed position. If spending may hours, days, months on the TT position I see that long term power as good as being more upright. This can be seen in TT specialists and some Tri riders that spend all the time riding this way. The body and power changes.
On hills many produce more power on a hill than on the flat. I expect that is due to opening up hip angle, and with that a lower cadence. But some will do similar longer time power in a TT position with more closed angle in higher cadence. So I'm not convinced how important the position is for those that train in it.
08-28-17, 09:31 AM
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Not trying to be a jerk, it comes naturally, but less than 5cm is not UCI legal. Why does that matter?
I just see a continuum of bikes and positions these days that take things from being a "road bike" to a recumbent and I look for definition so all know when they have moved to a different bike type. While I think UCI is stricter than required to define a road bike, they at least do provide a definition and it is worth noting when it is being deviated from.
08-28-17, 03:48 PM
#12
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Thread Starter
Some useful and interesting replies here - thank you!
Last edited by johngwheeler; 08-28-17 at 04:00 PM.
08-28-17, 04:00 PM
#13
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Thread Starter
I'm trying to learn about the parameters of bike fit, comfort & efficiency, but also trying to get my commuting bike into an optimal fit - it's probably the bike I spend most time on, after all. The experimentation is actually part of the fun, and I learn a lot about bikes, my body and my personal riding style.
I'm now being more disciplined in my changes: I change one thing and give it a good trial period - at least 50km, usually more, and try to include a longish ride (> 1.5 hours) because comfort issues often appear after an hour or two.
My changes are based on research, admittedly from the Internet, which contains multiple opinions, some of which are complete bunkum :-)
As regards fitters, yes I'd agree, getting expert advice is a good option. However, as with many things, there is a spectrum of ability and style amongst fitter. At a minimum of $100 a pop, I'd rather exhaust the free options of open-minded experimentation before playing lucky-dip trying to find a mystical guru fitter who gets it 100% right for me. In any case, fit is a evolutionary thing, so you don't just have one and call it good. I will no doubt go for another fitting, but only when I'm armed with enough experience and experimental data to know both what my preferences are and to recognise expertise when I see it. My instinct tells me that I will get a lot more out of a paid fitting if I have already done a fair bit of research and experimentation first, so that I can at least explain my findings to the fitter as part of the process.
Last edited by johngwheeler; 08-28-17 at 07:31 PM.
08-28-17, 04:08 PM
#14
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Thread Starter
Only since the beginning of this year.
Thanks. I'm now trying to ride with a flat back, by adjusting my pelvis position, which does seem to relax my neck and shoulders considerably and allow me to let my arms almost hang lightly on top of the bars. In this position I found the bar drop and reach to be too high and short respectively, hence my experiment with a longer stem. I may have overdone it with a 120mm stem (the previous riser stem was 105mm, but the difference in angle - 30 degree vs 8 - makes the reach difference 37mm).
For myself, finding the most efficient position took a few years of trial and error. There aren't any specific rules, only loose guidelines when it comes to fit vs comfort.
Seat position relative to bar position varies over time. As you ride, particularly if you ride in the drops, your back is able to flatten out, without tilting your pelvis forward. Nowadays the top of my bar is about 5cm lower than the nose of my saddle, and I am flexible enough to ride resting my forearms on the top of the bar. When I started riding road bikes, the bar was higher, and I wasn't at all flexible enough to ride with my arms on the bar.
If you start losing a lot of weight (as I did), comfort improves because your arms and butt are supporting less weight.
When racing in Europe, a coach there made two small recommendations to my setup; to move my seat a little more to the rear, and to tilt the nose up just few millimeters. At first the new position felt uncomfortable, but it made a noticeable improvement in my climbing.
Fit and comfort take a long time to get right. You can't really get it perfect, but you can get pretty close. Adjustments should be made one at a time, and you need to give yourself time to get used to them to see if they really make a difference. Don't adjust more than one thing at once, as one kind of adjustment can negate the effect of another adjustment.
Seat position relative to bar position varies over time. As you ride, particularly if you ride in the drops, your back is able to flatten out, without tilting your pelvis forward. Nowadays the top of my bar is about 5cm lower than the nose of my saddle, and I am flexible enough to ride resting my forearms on the top of the bar. When I started riding road bikes, the bar was higher, and I wasn't at all flexible enough to ride with my arms on the bar.
If you start losing a lot of weight (as I did), comfort improves because your arms and butt are supporting less weight.
When racing in Europe, a coach there made two small recommendations to my setup; to move my seat a little more to the rear, and to tilt the nose up just few millimeters. At first the new position felt uncomfortable, but it made a noticeable improvement in my climbing.
Fit and comfort take a long time to get right. You can't really get it perfect, but you can get pretty close. Adjustments should be made one at a time, and you need to give yourself time to get used to them to see if they really make a difference. Don't adjust more than one thing at once, as one kind of adjustment can negate the effect of another adjustment.
08-28-17, 04:15 PM
#15
Senior Member
Thread Starter
OP...fit is a work in progress. I have ridden in just about every position excepting mega drop like a TdF rider.
Pro's...not to extrapolate too closely even run over 100mm setback saddle nose to BB center...for some taller riders like Boonen. Some the same size ride less setback. More setback thwarts ability to ride aero because of constraining hip angle...why TT riders ride forward and doesn't hurt their speed. But as you say, there is more pressure on hands in a more forward position. TT riders hold up their almost horizontal torso with elbows...not core as with a road bike. But a data point about speed can be derived.
My personal belief is 'power' versus speed is more a function of hip angle which isn't dramatically different between road bike and TT bike as it turns out. Close the hip angle too much, and less leverage/power...but and big but....a more closed position is still generally faster because reduction in power is less than improvement in aerodynamics. Aero rules the day when riding over 20 mph on a road bike in terms of watt expenditure.
You maybe interested in this for reference:
Here is a chart for setback from B.Hinault's book and was used by all of Guimard's riders(Hinault, LeMond and Fignon). Measurement is from tip of the saddle nose to center of BB measured horizontally.
Cycling Inseam versus Saddle Setback
75 to 78cm. 4 to 6cm.
79 to 82cm. 5 to 7cm.
83 to 86cm. 6 to 8cm.
87 to 90cm. 7 to 9cm.
I think above is decent rule of thumb but as with many conventions, certainly not set in stone.
Further and not to put too much stock in pro riders, the trend has moved a bit toward less setback and even nose down saddle position based upon some relenting of the UCI. Keep in mind however, pros put out a lot higher average wattage which naturally unweighs the torso...so careful about adopting a pro position unless blessed with great flexibility and strong legs.
https://www.youtube.com/watch?v=69OzE3KB2IY
Pro's...not to extrapolate too closely even run over 100mm setback saddle nose to BB center...for some taller riders like Boonen. Some the same size ride less setback. More setback thwarts ability to ride aero because of constraining hip angle...why TT riders ride forward and doesn't hurt their speed. But as you say, there is more pressure on hands in a more forward position. TT riders hold up their almost horizontal torso with elbows...not core as with a road bike. But a data point about speed can be derived.
My personal belief is 'power' versus speed is more a function of hip angle which isn't dramatically different between road bike and TT bike as it turns out. Close the hip angle too much, and less leverage/power...but and big but....a more closed position is still generally faster because reduction in power is less than improvement in aerodynamics. Aero rules the day when riding over 20 mph on a road bike in terms of watt expenditure.
You maybe interested in this for reference:
Here is a chart for setback from B.Hinault's book and was used by all of Guimard's riders(Hinault, LeMond and Fignon). Measurement is from tip of the saddle nose to center of BB measured horizontally.
Cycling Inseam versus Saddle Setback
75 to 78cm. 4 to 6cm.
79 to 82cm. 5 to 7cm.
83 to 86cm. 6 to 8cm.
87 to 90cm. 7 to 9cm.
I think above is decent rule of thumb but as with many conventions, certainly not set in stone.
Further and not to put too much stock in pro riders, the trend has moved a bit toward less setback and even nose down saddle position based upon some relenting of the UCI. Keep in mind however, pros put out a lot higher average wattage which naturally unweighs the torso...so careful about adopting a pro position unless blessed with great flexibility and strong legs.
https://www.youtube.com/watch?v=69OzE3KB2IY
08-28-17, 04:17 PM
#16
Senior Member
Thread Starter
How saddle setback by itself affects power who can say - probably doesn't. But if you look at time trial setups, they like the saddle much more forward and tilted down, though you do tend to put more weight on your hands that way.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
08-28-17, 04:20 PM
#17
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Thread Starter
You're right that the bike is probably a size too small for me. It's a Giant TCX "medium", and I'm 177cm (5'9.5") with a 86cm (34") inseam. My long-for-height inseam means I'm generally better off on a bike one size larger than my height suggests, but I then have to play around with stem and saddle position in order to get comfortable.
08-28-17, 04:23 PM
#18
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The reason that TT (and especially triathlon) bikes have the butt forward is so that being low and aero doesn't require a super closed hip angle. This ends up putting a lot of weight on the upper body.... but aerobars put vertical support near the elbow, which helps make that easier, and simultaneously gives you nice aero level forearms.
If I'm trying to do a fast couple-minute effort on my drop bar bikes on level ground, I'll roll my hips forward until a narrow part of my sit bones are resting way out on the nose of the saddle, put my hands in the hooks, and hold my forearms level. I'm not just leaning my torso forward, I'm rotating my entire body forward relative to the bottom bracket; my torso-leg-pedal relationship barely scrunches up at all, and I can still breath and pedal nearly as well as I can if I'm riding in more "normal" positions... albeit with extra upper-body effort.
This is more or less what the old phrase "on the rivet" refers to. Although ironically, my only saddle with a rivet out front - a Brooks Swift - has a nose that's too narrow for me to roll forward onto.
If I'm trying to do a fast couple-minute effort on my drop bar bikes on level ground, I'll roll my hips forward until a narrow part of my sit bones are resting way out on the nose of the saddle, put my hands in the hooks, and hold my forearms level. I'm not just leaning my torso forward, I'm rotating my entire body forward relative to the bottom bracket; my torso-leg-pedal relationship barely scrunches up at all, and I can still breath and pedal nearly as well as I can if I'm riding in more "normal" positions... albeit with extra upper-body effort.
This is more or less what the old phrase "on the rivet" refers to. Although ironically, my only saddle with a rivet out front - a Brooks Swift - has a nose that's too narrow for me to roll forward onto.
08-28-17, 04:26 PM
#19
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How saddle setback by itself affects power who can say - probably doesn't. But if you look at time trial setups, they like the saddle much more forward and tilted down, though you do tend to put more weight on your hands that way.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
The whole saddle set-back for weight balance paradigm is what's causing your consternation. The balance including weight on your hands comes from your entire position and pedaling mechanics.
Lowering the bars for wind advantage increases the angle at hips and brings knees closer to gut. Moving seat forward and up to compensate.
Lowering the bars also changes the body angle, and puts more weight on a person's tender parts. Pointing seat towards bars helps get the weight off of those sensitive body parts.
I'm not convinced power is the issue.
08-28-17, 05:07 PM
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TT position is a bit more like running on the pedals too. More a stomp stomp, not a circle.
Qualifier - Copying Martin for the ITT is like copying Froome for hill climbing - don't.
Qualifier - Copying Martin for the ITT is like copying Froome for hill climbing - don't.
08-28-17, 06:02 PM
#21
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I think you are chasing your tail trying to find a comfortable fit. You are new to cycling and it takes a while for your body to get conditioned to it.
If you go out for a long ride and something is uncomfortable it doesn't mean it is the fit.
Just set it up with a good "middle of the road" fit and ride it.
Also if you are no longer a young man, things just hurt more.
I am 51 now and have been riding since my youth. Sometimes I may get a sore knee, neck, back, whatever.
It never used to happen. I am happy with my bike fit. I just aren't 20 anymore!
If you go out for a long ride and something is uncomfortable it doesn't mean it is the fit.
Just set it up with a good "middle of the road" fit and ride it.
Also if you are no longer a young man, things just hurt more.
I am 51 now and have been riding since my youth. Sometimes I may get a sore knee, neck, back, whatever.
It never used to happen. I am happy with my bike fit. I just aren't 20 anymore!
08-28-17, 07:41 PM
#22
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Thread Starter
I think you are chasing your tail trying to find a comfortable fit. You are new to cycling and it takes a while for your body to get conditioned to it.
If you go out for a long ride and something is uncomfortable it doesn't mean it is the fit.
Just set it up with a good "middle of the road" fit and ride it.
Also if you are no longer a young man, things just hurt more.
I am 51 now and have been riding since my youth. Sometimes I may get a sore knee, neck, back, whatever.
It never used to happen. I am happy with my bike fit. I just aren't 20 anymore!
If you go out for a long ride and something is uncomfortable it doesn't mean it is the fit.
Just set it up with a good "middle of the road" fit and ride it.
Also if you are no longer a young man, things just hurt more.
I am 51 now and have been riding since my youth. Sometimes I may get a sore knee, neck, back, whatever.
It never used to happen. I am happy with my bike fit. I just aren't 20 anymore!
I am trying to get at least to an acceptable level of comfort whilst adopting "good style". I only recently read about propert "flat back" posture, and this has gone a long way to reducing neck and upper back tension that was making my long rides a painful experience. I'm only one year your junior, but went back to cycling at the beginning of this year after a 35 year hiatus!
But I also must admit to enjoy the experimentation side of things at the moment. I might be going in circles, but as long as I note down my findings, then I will at least discover something, and may even be able to give some advice to others eventually. This seems to have more validity than just following some rules that "I read on the Internet", which may or may not be the right advice for the individual :-)
08-28-17, 08:22 PM
#23
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FWIW I am an inch taller than you with inseam of 34.5"+. I also ride a medium TCX. 785mm saddle height. 85mm set back. 125mm stem. Frame size is just right for me. Also on a 56cm Domane and Madone. 110mm stem.
08-28-17, 10:01 PM
#24
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Thread Starter
I also have a Spec Roubaix, which I got in 56cm - the 54cm felt too cramped for me.
Your saddle set-back seems to be a more typical 85mm (is this with the standard Giant Contact saddle?), so maybe mine is a bit far back. Do you find your balance / weight-distribution is OK with long stem, compared tot he default 90mm the Medium TCX comes with?
08-29-17, 12:48 AM
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It is the standard Giant saddle. 10mm spacer under the stem flipped down. About 10cm of saddle/bar drop. There obviously is a fairly wide range of saddle/bar drop between riders, basically coming down to application and personal comfort.
It is often said to be a flexibility thing, but I don't think this is completely true. My back mobility isn't that good and I have tight hamstrings from years of cycling and not stretching nearly as much as I should.
If you look at a rider on a bike you can see that you aren't really bent over that much and your leg doesn't go fully straight either, so nothing like putting your palms on the ground with straight legs or even just touching your toes.
It is often said to be a flexibility thing, but I don't think this is completely true. My back mobility isn't that good and I have tight hamstrings from years of cycling and not stretching nearly as much as I should.
If you look at a rider on a bike you can see that you aren't really bent over that much and your leg doesn't go fully straight either, so nothing like putting your palms on the ground with straight legs or even just touching your toes.