Custom bike, can't find a good position.
08-16-22, 05:24 AM
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Custom bike, can't find a good position.
hey all, i have custom bike that intended to be an off road touring bike.
as i trust my framebuilder he decided that i need 76 Degrees STA!
the measurements that he askes for was:
1. inseam length
2. shin length(from the floor to under the patella)
3. torso length
i haven't seen him as im from a country where no framebuilders available(israel)
he told me i have a very long shin compared to the femur and i need 76 degrees STA.
only afterwards i understand that most of the time only TT bikes have this steep of STA angle.
nevertheless, the bike is nice, and this is the only problem, when im using inline seatpost and seat centered on the rails, i feel like im falling on the handlebars.
in this time i understand that KOPS is totally ********, yes, my knee was over the spindle but im kind of sitting on the handlebars.
the problem is that even when im using 30mm layback seatpost and seatpost all the way backwards, im still not comfortable.
the seatpost im using is velo orange grand cru 30mm layback.
what can i do?
i waste a lot of money on this frame and the framebuilder says he never was wrong in designing a frame.
i really want to write on him a negative review but i also wants a bike i can ride comfortabely!
im so pissed, it was a long process for nothing.
my body stats:
height: 1.85cm
inseam: 91.5
i do feel that when im pedaling with inline post and seat centered that im pedaling effectively, but my hands bearing a lot of my weight even when seat and handlebars are in the same height.
when im using the setup of 30mm layback and seat all the way rearward i need to lower the seat a little bit cause im over reaching the pedals, but my weight desaturation feels better, although not close to what i was really wanted.
what can i do to understand my correct STA?
what will you do if you been in my situation?
and advice will be appreciated.
Thank you
as i trust my framebuilder he decided that i need 76 Degrees STA!
the measurements that he askes for was:
1. inseam length
2. shin length(from the floor to under the patella)
3. torso length
i haven't seen him as im from a country where no framebuilders available(israel)
he told me i have a very long shin compared to the femur and i need 76 degrees STA.
only afterwards i understand that most of the time only TT bikes have this steep of STA angle.
nevertheless, the bike is nice, and this is the only problem, when im using inline seatpost and seat centered on the rails, i feel like im falling on the handlebars.
in this time i understand that KOPS is totally ********, yes, my knee was over the spindle but im kind of sitting on the handlebars.
the problem is that even when im using 30mm layback seatpost and seatpost all the way backwards, im still not comfortable.
the seatpost im using is velo orange grand cru 30mm layback.
what can i do?
i waste a lot of money on this frame and the framebuilder says he never was wrong in designing a frame.
i really want to write on him a negative review but i also wants a bike i can ride comfortabely!
im so pissed, it was a long process for nothing.
my body stats:
height: 1.85cm
inseam: 91.5
i do feel that when im pedaling with inline post and seat centered that im pedaling effectively, but my hands bearing a lot of my weight even when seat and handlebars are in the same height.
when im using the setup of 30mm layback and seat all the way rearward i need to lower the seat a little bit cause im over reaching the pedals, but my weight desaturation feels better, although not close to what i was really wanted.
what can i do to understand my correct STA?
what will you do if you been in my situation?
and advice will be appreciated.
Thank you
08-17-22, 06:51 AM
#2
Banned.
76 degrees with 30 cm setback seatpost and saddle all the way back should be enough already.
If you still feel like falling over, tilt the seat/saddle to level or slightly upward.
If you're still feeling the weight on your hands, get shorter stem, 20 to 30 mm shorter and/or raise the handlebar height.
One way you can reduce STA is get longer fork or even suspension fork since you'll be doing off road touring anyway, it may not be a bad option. But the longer fork will also raise your bike's "standover height" and may cause a problem with your taint hitting the top tube if get off the seat during stops.
Don't try to further increase the setback of your seat post or get saddle with longer rails so you can adjust them further back. Such adjustment could break the seatpost and damage the seat tube.
And finally, it will some getting use to the steeper STA. Give it a month or two. Might actually work out well.
If you still feel like falling over, tilt the seat/saddle to level or slightly upward.
If you're still feeling the weight on your hands, get shorter stem, 20 to 30 mm shorter and/or raise the handlebar height.
One way you can reduce STA is get longer fork or even suspension fork since you'll be doing off road touring anyway, it may not be a bad option. But the longer fork will also raise your bike's "standover height" and may cause a problem with your taint hitting the top tube if get off the seat during stops.
Don't try to further increase the setback of your seat post or get saddle with longer rails so you can adjust them further back. Such adjustment could break the seatpost and damage the seat tube.
And finally, it will some getting use to the steeper STA. Give it a month or two. Might actually work out well.
08-17-22, 08:15 AM
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I have been a store owner for over 12 years and frame builder for over 20. I am having a hard time understanding your complaints / description of discomfort. Hands bearing a lot of weight generally is not going to have to do with your steep seat tube angle. It sounds like your seat is pointed down more than 4mm. It could be that your effective reach (the distance from your saddle nose to your handlebar center) is off?? I am short only 167.4cms. I have short thighs. I never build bikes with steeper than a 75 degree seat angle for myself. For someone your height I would think 73 degrees would be more in line. With a 30mm offset seat post this should have you correctly over the pedals. (I was unaware such setback was even available.)
08-17-22, 10:18 AM
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Not the first custom bike disaster I've heard of. Something went wrong. If you have long tibia for your pubic bone to floor distance, you must have short femurs and would need a more forward saddle. but that doesn't seem to be the case, judging by the uncomfortable result.
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here: https://www.bikeforums.net/21296948-post3.html
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here: https://www.bikeforums.net/21296948-post3.html
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08-17-22, 10:23 AM
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your post does lack some clarity, not related to any language issue.
your height is not 1.85 cm - is 1.85 M ?
is your inseam measurement as quoted - 91.5 cm - 'cycling' inseam - usually measured floor to bottom of pubic ischium (ramus) ? is not your pants inseam ?
91.5 cm would indicate a slightly longer than average leg length for someone 185 cm, but not major difference.
you don't mention your saddle extension (with reference on how the number/measurement is done)
but given it's prolly in the neighborhood of 80ish cm - Center of BB to some point called 'saddle top' (assuming 175 crank length and about 46-47 shoe size)
Most road bike frames in larger size would have a 73-72 deg STA, mtb most use 1 deg steeper - 74-73, TT bikes 2+ steeper 76-75...
most 'gravel type bikes have similar STA angles to road and the Head tube angle is slacken a bit...
not uncommon to have a larger road frame like 60 cm and greater to have a 72 deg STA...
so
your bike, with seat centered on a zero-offset seat post, extended to 80 cm height, with STA of 76 - compared to a 73 deg. STA = seat tube is 4 cm further forward for 76 STA
comparing to what often is found on large frames - 72 STA - the 76 STA will put you 6 CM further forward...
both measurement differences are quite large.
you have a 30mm setback seatpost - most riders normally will have a setback post of -15 to 25 cm... quite a few riders with shorter legs use a zero setback post... but they are compensating for shorter legs - you have the opposite.
you don;t mention what Stem Length and angle you are using ???? important !
what you might be able to do...
make sure your saddle is 'neutral'/flat/horizontal, not tilted forward
make sure it has CroMo saddle rails and move it as far back as possible (knowing that whatever weight you are, you might eventually bend the saddle rails...) minimum of 2, even 3 cm back from center...
WHAT IS YOUR STEM LENGTH and ANGLE ?
in any case, DO NOT go shorter, go longer, at least 20 mm but longer than 20 mm might even improve things more...
You don;t mention what the Frame 'Stack' is or the Headtube length - given some 'normal' stack or length for the frame size - raising the bars , stack, may not do much for changing weight distribution - used more for 'posture' adjustment...
Posting in the 'Frame Builders' may give you some further comments and variation of consideration... But They will also want more info and accuracy...
I don;t think there is any viable (and economic) way to alter the STA on your frame.
YMMV...
Ride On
Yuri
your height is not 1.85 cm - is 1.85 M ?
is your inseam measurement as quoted - 91.5 cm - 'cycling' inseam - usually measured floor to bottom of pubic ischium (ramus) ? is not your pants inseam ?
91.5 cm would indicate a slightly longer than average leg length for someone 185 cm, but not major difference.
you don't mention your saddle extension (with reference on how the number/measurement is done)
but given it's prolly in the neighborhood of 80ish cm - Center of BB to some point called 'saddle top' (assuming 175 crank length and about 46-47 shoe size)
Most road bike frames in larger size would have a 73-72 deg STA, mtb most use 1 deg steeper - 74-73, TT bikes 2+ steeper 76-75...
most 'gravel type bikes have similar STA angles to road and the Head tube angle is slacken a bit...
not uncommon to have a larger road frame like 60 cm and greater to have a 72 deg STA...
so
your bike, with seat centered on a zero-offset seat post, extended to 80 cm height, with STA of 76 - compared to a 73 deg. STA = seat tube is 4 cm further forward for 76 STA
comparing to what often is found on large frames - 72 STA - the 76 STA will put you 6 CM further forward...
both measurement differences are quite large.
you have a 30mm setback seatpost - most riders normally will have a setback post of -15 to 25 cm... quite a few riders with shorter legs use a zero setback post... but they are compensating for shorter legs - you have the opposite.
you don;t mention what Stem Length and angle you are using ???? important !
what you might be able to do...
make sure your saddle is 'neutral'/flat/horizontal, not tilted forward
make sure it has CroMo saddle rails and move it as far back as possible (knowing that whatever weight you are, you might eventually bend the saddle rails...) minimum of 2, even 3 cm back from center...
WHAT IS YOUR STEM LENGTH and ANGLE ?
in any case, DO NOT go shorter, go longer, at least 20 mm but longer than 20 mm might even improve things more...
You don;t mention what the Frame 'Stack' is or the Headtube length - given some 'normal' stack or length for the frame size - raising the bars , stack, may not do much for changing weight distribution - used more for 'posture' adjustment...
Posting in the 'Frame Builders' may give you some further comments and variation of consideration... But They will also want more info and accuracy...
I don;t think there is any viable (and economic) way to alter the STA on your frame.
YMMV...
Ride On
Yuri
Last edited by cyclezen; 08-17-22 at 10:28 AM.
08-17-22, 10:50 AM
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I would run from any framebuilder who does not understand a very steep STA puts more weight into your torso and onto hands
Think of the opposite of a steep STA, say around 20 degrees. There is zero weight on the hands and your core is completely relaxed.
A rider your size probably needs 72-73 degree STA to achieve a balanced, comfortable position on a road bike. I doubt any seatpost and stem combo can get you into such a position.
I would write it off as a bad experience.
Think of the opposite of a steep STA, say around 20 degrees. There is zero weight on the hands and your core is completely relaxed.
A rider your size probably needs 72-73 degree STA to achieve a balanced, comfortable position on a road bike. I doubt any seatpost and stem combo can get you into such a position.
I would write it off as a bad experience.
08-17-22, 11:18 PM
#7
Banned.
I have been a store owner for over 12 years and frame builder for over 20. I am having a hard time understanding your complaints / description of discomfort. Hands bearing a lot of weight generally is not going to have to do with your steep seat tube angle. It sounds like your seat is pointed down more than 4mm. It could be that your effective reach (the distance from your saddle nose to your handlebar center) is off?? I am short only 167.4cms. I have short thighs. I never build bikes with steeper than a 75 degree seat angle for myself. For someone your height I would think 73 degrees would be more in line. With a 30mm offset seat post this should have you correctly over the pedals. (I was unaware such setback was even available.)
With posture 1, my seat position is close to TT and only have little pressure on my arms and hands. No numbness, no back soreness even on long 6 hr rides.
It's disturbing to note there are many internet articles saying that Posture 2 is correct and 1 is wrong. Quite contrary to the fact the vast majority of Pro tour riders have Posture 1. Those pro riders aren't masochists who wants more pain. Racing is already very hard and painful and the last thing you'll want is make it feel even harder. These riders will exploit every ounce of comfort if it doesn't compromise performance very much.
Pro racer posture (Albert Contador)
Last edited by koala logs; 08-17-22 at 11:36 PM.
08-18-22, 06:47 AM
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I have been a store owner for over 12 years and frame builder for over 20. I am having a hard time understanding your complaints / description of discomfort. Hands bearing a lot of weight generally is not going to have to do with your steep seat tube angle. It sounds like your seat is pointed down more than 4mm. It could be that your effective reach (the distance from your saddle nose to your handlebar center) is off?? I am short only 167.4cms. I have short thighs. I never build bikes with steeper than a 75 degree seat angle for myself. For someone your height I would think 73 degrees would be more in line. With a 30mm offset seat post this should have you correctly over the pedals. (I was unaware such setback was even available.)
08-18-22, 06:50 AM
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[QUOTE=Carbonfiberboy;22613428]Not the first custom bike disaster I've heard of. Something went wrong. If you have long tibia for your pubic bone to floor distance, you must have short femurs and would need a more forward saddle. but that doesn't seem to be the case, judging by the uncomfortable result.
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here:
cheers, thank you.
ill check if i can get custom seatpost for that purpose
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here:
cheers, thank you.
ill check if i can get custom seatpost for that purpose
08-18-22, 07:00 AM
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your post does lack some clarity, not related to any language issue.
your height is not 1.85 cm - is 1.85 M ?
is your inseam measurement as quoted - 91.5 cm - 'cycling' inseam - usually measured floor to bottom of pubic ischium (ramus) ? is not your pants inseam ?
91.5 cm would indicate a slightly longer than average leg length for someone 185 cm, but not major difference.
you don't mention your saddle extension (with reference on how the number/measurement is done)
but given it's prolly in the neighborhood of 80ish cm - Center of BB to some point called 'saddle top' (assuming 175 crank length and about 46-47 shoe size)
Most road bike frames in larger size would have a 73-72 deg STA, mtb most use 1 deg steeper - 74-73, TT bikes 2+ steeper 76-75...
most 'gravel type bikes have similar STA angles to road and the Head tube angle is slacken a bit...
not uncommon to have a larger road frame like 60 cm and greater to have a 72 deg STA...
so
your bike, with seat centered on a zero-offset seat post, extended to 80 cm height, with STA of 76 - compared to a 73 deg. STA = seat tube is 4 cm further forward for 76 STA
comparing to what often is found on large frames - 72 STA - the 76 STA will put you 6 CM further forward...
both measurement differences are quite large.
you have a 30mm setback seatpost - most riders normally will have a setback post of -15 to 25 cm... quite a few riders with shorter legs use a zero setback post... but they are compensating for shorter legs - you have the opposite.
you don;t mention what Stem Length and angle you are using ???? important !
what you might be able to do...
make sure your saddle is 'neutral'/flat/horizontal, not tilted forward
make sure it has CroMo saddle rails and move it as far back as possible (knowing that whatever weight you are, you might eventually bend the saddle rails...) minimum of 2, even 3 cm back from center...
WHAT IS YOUR STEM LENGTH and ANGLE ?
in any case, DO NOT go shorter, go longer, at least 20 mm but longer than 20 mm might even improve things more...
You don;t mention what the Frame 'Stack' is or the Headtube length - given some 'normal' stack or length for the frame size - raising the bars , stack, may not do much for changing weight distribution - used more for 'posture' adjustment...
Posting in the 'Frame Builders' may give you some further comments and variation of consideration... But They will also want more info and accuracy...
I don;t think there is any viable (and economic) way to alter the STA on your frame.
YMMV...
Ride On
Yuri
your height is not 1.85 cm - is 1.85 M ?
is your inseam measurement as quoted - 91.5 cm - 'cycling' inseam - usually measured floor to bottom of pubic ischium (ramus) ? is not your pants inseam ?
91.5 cm would indicate a slightly longer than average leg length for someone 185 cm, but not major difference.
you don't mention your saddle extension (with reference on how the number/measurement is done)
but given it's prolly in the neighborhood of 80ish cm - Center of BB to some point called 'saddle top' (assuming 175 crank length and about 46-47 shoe size)
Most road bike frames in larger size would have a 73-72 deg STA, mtb most use 1 deg steeper - 74-73, TT bikes 2+ steeper 76-75...
most 'gravel type bikes have similar STA angles to road and the Head tube angle is slacken a bit...
not uncommon to have a larger road frame like 60 cm and greater to have a 72 deg STA...
so
your bike, with seat centered on a zero-offset seat post, extended to 80 cm height, with STA of 76 - compared to a 73 deg. STA = seat tube is 4 cm further forward for 76 STA
comparing to what often is found on large frames - 72 STA - the 76 STA will put you 6 CM further forward...
both measurement differences are quite large.
you have a 30mm setback seatpost - most riders normally will have a setback post of -15 to 25 cm... quite a few riders with shorter legs use a zero setback post... but they are compensating for shorter legs - you have the opposite.
you don;t mention what Stem Length and angle you are using ???? important !
what you might be able to do...
make sure your saddle is 'neutral'/flat/horizontal, not tilted forward
make sure it has CroMo saddle rails and move it as far back as possible (knowing that whatever weight you are, you might eventually bend the saddle rails...) minimum of 2, even 3 cm back from center...
WHAT IS YOUR STEM LENGTH and ANGLE ?
in any case, DO NOT go shorter, go longer, at least 20 mm but longer than 20 mm might even improve things more...
You don;t mention what the Frame 'Stack' is or the Headtube length - given some 'normal' stack or length for the frame size - raising the bars , stack, may not do much for changing weight distribution - used more for 'posture' adjustment...
Posting in the 'Frame Builders' may give you some further comments and variation of consideration... But They will also want more info and accuracy...
I don;t think there is any viable (and economic) way to alter the STA on your frame.
YMMV...
Ride On
Yuri
my 91.5 inseam was measured in a bike shop fitting machine, so i guess its my cycling inseam. no shoes.
shoe size is 45 and top of saddle is 80cm to center of bottom bracket.
im using 100 stem length with a positive 7 degrees.
stack: 601mm
head tube length: 125mm
head tube angle: 70 degrees
reach: 390mm
top tube length(effective): 540mm
my friend thought i had more then 76 STA.
this is the result: 76.98, more crazy then was intended.
Likes For Chilik:
08-18-22, 07:01 AM
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I would run from any framebuilder who does not understand a very steep STA puts more weight into your torso and onto hands
Think of the opposite of a steep STA, say around 20 degrees. There is zero weight on the hands and your core is completely relaxed.
A rider your size probably needs 72-73 degree STA to achieve a balanced, comfortable position on a road bike. I doubt any seatpost and stem combo can get you into such a position.
I would write it off as a bad experience.
Think of the opposite of a steep STA, say around 20 degrees. There is zero weight on the hands and your core is completely relaxed.
A rider your size probably needs 72-73 degree STA to achieve a balanced, comfortable position on a road bike. I doubt any seatpost and stem combo can get you into such a position.
I would write it off as a bad experience.
08-18-22, 07:46 AM
#13
Banned.
Not the best idea. Such seatposts with huge setback are prone to breaking especially for heavy riders and they can damage the seat tube or cause premature failure from greater forces transmitted to the seat tube. I think the manufactured ones may indicate rider weight limit.
If considering one, at least get a long one that goes deep into the seat tube to avoid stressing the seat tube excessively.
Would help diagnosing the problem better if you can post a picture of your riding posture on your bike. Solutions can be found elsewhere.
If considering one, at least get a long one that goes deep into the seat tube to avoid stressing the seat tube excessively.
Would help diagnosing the problem better if you can post a picture of your riding posture on your bike. Solutions can be found elsewhere.
08-18-22, 10:44 AM
#14
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185cm height.
my 91.5 inseam was measured in a bike shop fitting machine, so i guess its my cycling inseam. no shoes.
shoe size is 45 and top of saddle is 80cm to center of bottom bracket.
im using 100 stem length with a positive 7 degrees.
stack: 601mm
head tube length: 125mm
head tube angle: 70 degrees
reach: 390mm
top tube length(effective): 540mm
my friend thought i had more then 76 STA.
this is the result: 76.98, more crazy then was intended.
my 91.5 inseam was measured in a bike shop fitting machine, so i guess its my cycling inseam. no shoes.
shoe size is 45 and top of saddle is 80cm to center of bottom bracket.
im using 100 stem length with a positive 7 degrees.
stack: 601mm
head tube length: 125mm
head tube angle: 70 degrees
reach: 390mm
top tube length(effective): 540mm
my friend thought i had more then 76 STA.
this is the result: 76.98, more crazy then was intended.
390 'Reach' is a very median measure for a non-road race, but drop bar bike - for the probable frame size for your height/inseam.
so, aside from the steep STA, the bike might work ok...
assuming that the chainstay length is not too short - more like 425mm or greater... as I noted earlier, move the saddle back 2 cm, on the 30 mm offset seatpost (if you currently have the saddle centered on the rails) , ride, and if improves your REAR position and feels good for the legs, you can try going back even further... But for now, ride it that way for a few rides, before going back further...
This is NOT recommended for saddles with carbon fiber rails, saddles with Titanium or magnesium rails may also bend badly over time - but's it's only the saddle... I would recommend staying with a saddle with CroMo rails... 30 mm offset seatpost not a problem, as long as you have at least 110 - 120 minimum seat post inserted into the seat tube.
Important is getting the saddle set to what works best for you - the 'cockpit' (bars/stem) is then set for what works for you...
the slightly shorter (though not outlandish) Effective TT reflects the 70 deg HT and a slightly steeper ST - but given the HT length, the frame may be on a slightly smaller overall size anyway.
Back to cockpit:
SO, if you still feel that that you're too far over the 'front wheel' - buy a longer stem - I would think a 120 mm stem would be fine. If... you want to experiment... you could buy an ' 130 mm adjustable stem (amazon link)' - and vary the 'angle' to find what feels best.
a 130 stem set to +7 deg would be 12mm higher than your current 100, and 27 mm further forward...
the little bit more reach to the bars will take some perceived 'weight' off the hands. vary and you can find what feels best to you.
... it's up to you for your riding posture..
bring a positive attitude to the issues... don;t let the perceived STA issue play with your mind... you have plenty of leg length and moving the saddle back isn;t going to create any problems which you don;t have...
Ride On
Yuri
EDIT: once you've determined a good stem angle, then you could use adjustable stem as is set, or buy a stem config'd for that angle - realizing that as you vary the angle - up or down - the 'actual' forward length will vary ...
I also recommend trying the 'adjustable stem' set so it's completely horizontal to the ground - so that you get a good 'feel' what what a strong reach actually does to your riding 'feel. Then, you'll have some idea how stem rise and reach affects you.
.
Last edited by cyclezen; 08-18-22 at 10:58 AM.
08-18-22, 07:15 PM
#15
just another gosling
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[QUOTE=Chilik;22614408]
A good machine shop has a some sense of proper engineering. TIG welds are very strong.
Not the first custom bike disaster I've heard of. Something went wrong. If you have long tibia for your pubic bone to floor distance, you must have short femurs and would need a more forward saddle. but that doesn't seem to be the case, judging by the uncomfortable result.
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here:
cheers, thank you.
ill check if i can get custom seatpost for that purpose
I understand the issue but I think you are measuring KOPS incorrectly. One has KOPS when a plumb bob dropped from the bony protrusion below the knee cap bisects the pedal spindle, cranks horizontal. It's a decent starting point. I get it, you're really in a TT position and would love to rest your forearms on some aero bars. I ride a small frame. To avoid toe overlap, my seat tube is also steeper than I would like. I also use a 30mm setback and my saddle is all the way back on the rails. So far I've never broken a rail - 145-150 lbs.
I'd look into having a machine shop modify a seat post to give you the setback you need. You could put on a relatively narrow cheapo flat saddle and experiment with butt setback to see how much more you need. When you get that about right, look in a mirror and see how long a stem you'd need so that your upper arms make a right angle with your torso, hands on hoods. For reference, I have a fit primer post here:
cheers, thank you.
ill check if i can get custom seatpost for that purpose
__________________
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08-19-22, 11:10 AM
#16
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I'm thinking that somehow you and the frame builder got crossed up on what the bike was actually supposed to be for.
The only other possible thing from what I envision as the bike you wanted is that perhaps they had a frame already built for someone else and the deal fell through and you were just the means for them to get rid of the frame.
The only other possible thing from what I envision as the bike you wanted is that perhaps they had a frame already built for someone else and the deal fell through and you were just the means for them to get rid of the frame.
Last edited by Iride01; 08-19-22 at 11:21 AM.
08-19-22, 11:58 AM
#17
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No answers here but I completely get unusual bike setups working for certain people. I ride 58-59 cm bikes, 74-75 ST, very long reach (stems 140 to a lot longer) and have my saddles placed midway on the rails with 60mm setback posts. This gives me the correct location over the BB, the rear wheel in close for better handling on rough descents (ie, less scary and less skidding on poor surfaces out-of -the-saddle climbing). A reach that stretches my back and allows all day comfort as well as being less tiring upwind (my nemesis being skinny). And yes, I have real weight on my hands. I deal with it by using handlebars that work for them and paying a lot of attention to the rotation angle of the handlebars and location of the brake levers. All bikes get rides without bar tape so I can locate stuff on the road. First tape job is cloth wrapped from the bottom so I can unwrap, move levers and cables as needed and re-wrap.
So, OP, I recommend you do real work to dial in your handlebars and brake levers. Try my bar tape trick and go for those rides with all the wrenches. (I have to bring both the Allen key for the brake levers and a 6" crescent to put on it for leverage.) This doesn't sound entirely obvious, but I do best when the bars and levers are rotated forward and down so my hands are rotated down, pulling my pinkie back and thumb forward. Bars tipped back to "be comfortable" cause me numbness and pain riding that lasts long afterwards.
So, OP, I recommend you do real work to dial in your handlebars and brake levers. Try my bar tape trick and go for those rides with all the wrenches. (I have to bring both the Allen key for the brake levers and a 6" crescent to put on it for leverage.) This doesn't sound entirely obvious, but I do best when the bars and levers are rotated forward and down so my hands are rotated down, pulling my pinkie back and thumb forward. Bars tipped back to "be comfortable" cause me numbness and pain riding that lasts long afterwards.
08-19-22, 06:48 PM
#18
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for yuri.
i cant quote your post unfortunately.
hey, thank you
A-C is 425mm
the bike is for off road touring, mainly gravel roads.
im using 29X2.1 tires.
i have Rocker dropouts so Chainstay length is between 430-445 approximately.
it does play my mind, im very pissed on the framebuilder, a lot of it related to the fact the he cant admit he make a mistake, this STA is crazy, and what even crazier is that i measured the angle myself and its even steeper! 69.98!
nevertheless, i will try to use your advices in hope it will work out, appreciate you!
i cant quote your post unfortunately.
hey, thank you
A-C is 425mm
the bike is for off road touring, mainly gravel roads.
im using 29X2.1 tires.
i have Rocker dropouts so Chainstay length is between 430-445 approximately.
it does play my mind, im very pissed on the framebuilder, a lot of it related to the fact the he cant admit he make a mistake, this STA is crazy, and what even crazier is that i measured the angle myself and its even steeper! 69.98!
nevertheless, i will try to use your advices in hope it will work out, appreciate you!
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08-19-22, 06:53 PM
#19
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I'm thinking that somehow you and the frame builder got crossed up on what the bike was actually supposed to be for.
The only other possible thing from what I envision as the bike you wanted is that perhaps they had a frame already built for someone else and the deal fell through and you were just the means for them to get rid of the frame.
The only other possible thing from what I envision as the bike you wanted is that perhaps they had a frame already built for someone else and the deal fell through and you were just the means for them to get rid of the frame.
i told him the bike is for off road touring, i dont believe the bike was intended to someone else as he is very small manufacture.
Last edited by Chilik; 08-19-22 at 06:56 PM.
08-19-22, 06:56 PM
#20
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No answers here but I completely get unusual bike setups working for certain people. I ride 58-59 cm bikes, 74-75 ST, very long reach (stems 140 to a lot longer) and have my saddles placed midway on the rails with 60mm setback posts. This gives me the correct location over the BB, the rear wheel in close for better handling on rough descents (ie, less scary and less skidding on poor surfaces out-of -the-saddle climbing). A reach that stretches my back and allows all day comfort as well as being less tiring upwind (my nemesis being skinny). And yes, I have real weight on my hands. I deal with it by using handlebars that work for them and paying a lot of attention to the rotation angle of the handlebars and location of the brake levers. All bikes get rides without bar tape so I can locate stuff on the road. First tape job is cloth wrapped from the bottom so I can unwrap, move levers and cables as needed and re-wrap.
So, OP, I recommend you do real work to dial in your handlebars and brake levers. Try my bar tape trick and go for those rides with all the wrenches. (I have to bring both the Allen key for the brake levers and a 6" crescent to put on it for leverage.) This doesn't sound entirely obvious, but I do best when the bars and levers are rotated forward and down so my hands are rotated down, pulling my pinkie back and thumb forward. Bars tipped back to "be comfortable" cause me numbness and pain riding that lasts long afterwards.
So, OP, I recommend you do real work to dial in your handlebars and brake levers. Try my bar tape trick and go for those rides with all the wrenches. (I have to bring both the Allen key for the brake levers and a 6" crescent to put on it for leverage.) This doesn't sound entirely obvious, but I do best when the bars and levers are rotated forward and down so my hands are rotated down, pulling my pinkie back and thumb forward. Bars tipped back to "be comfortable" cause me numbness and pain riding that lasts long afterwards.
08-20-22, 12:35 AM
#21
OM boy
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for yuri.
i cant quote your post unfortunately.
hey, thank you
A-C is 425mm
the bike is for off road touring, mainly gravel roads.
im using 29X2.1 tires.
i have Rocker dropouts so Chainstay length is between 430-445 approximately.
it does play my mind, im very pissed on the framebuilder, a lot of it related to the fact the he cant admit he make a mistake, this STA is crazy, and what even crazier is that i measured the angle myself and its even steeper! 69.98!
nevertheless, i will try to use your advices in hope it will work out, appreciate you!
i cant quote your post unfortunately.
hey, thank you
A-C is 425mm
the bike is for off road touring, mainly gravel roads.
im using 29X2.1 tires.
i have Rocker dropouts so Chainstay length is between 430-445 approximately.
it does play my mind, im very pissed on the framebuilder, a lot of it related to the fact the he cant admit he make a mistake, this STA is crazy, and what even crazier is that i measured the angle myself and its even steeper! 69.98!
nevertheless, i will try to use your advices in hope it will work out, appreciate you!
same idea for the chainstays. So the builder did accommodate for a lot of your wants/needs.
I think, in all, the bike should performance fine for what you're looking for, if you make those saddle setback adjustments and work with a longer stem.
I think you'll really benefit from testing with an adjustable stem. Actually ride in a number of different settings, both in conditions which you think will be the dominant condition, as well as what you expect to be the most difficult.
Off-road riding is really affected by stem length and angle/rise, for what might be the best optimum position for any rider. In spite of being a dyed-in-the-wool 'roadie', I will admit its easy to adapt to different cockpit setups for road riding - might not be 'preferred', but adapting is mostly easy... Not so much for offroad. Stem/cockpit setup sure makes a big difference, not just in comfort, but also perceived 'control'. Just a lot more 'technical' going on... Off-road is way more '3-D' than road...
I think you have a good shot at getting the setup to work well for you.
Ride On
Yuri
08-20-22, 07:55 AM
#22
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So many complicated factors to this fit issue.
On the face of it, 76 degrees does sound quite steep and I usually recommend much slacker seat tube angles.
However, If you can position yourself to KOPS, and your not way in front of KOPS, then on paper, the builder has built the frame correctly, not withstanding that KOPS isn't the be all and end all of everything.
Now I don't want to be rude, but are you overweight?
Bicycles are just not comfortable, and they never will be for overweight riders. There always will be too much weight on your hands/arms/shoulders if you are overweight.
Catch 22 here I know.
A couple of suggestions. Set the seat back as far as you can and raise the handlebars significantly.
Something that's counterintuitive is that some people find it more comfortable to stretch out their reach to the bars rather than bringing the bars close when they feel like there is too much weight on their hands.
There's definitely a communication problem going on, and personally I would have asked a LOT of questions first before specifying a 76 degree seat tube angle, however if you achieve KOPS and aren't in front of KOPS, then the builder isn't necessarily wrong.
On the face of it, 76 degrees does sound quite steep and I usually recommend much slacker seat tube angles.
However, If you can position yourself to KOPS, and your not way in front of KOPS, then on paper, the builder has built the frame correctly, not withstanding that KOPS isn't the be all and end all of everything.
Now I don't want to be rude, but are you overweight?
Bicycles are just not comfortable, and they never will be for overweight riders. There always will be too much weight on your hands/arms/shoulders if you are overweight.
Catch 22 here I know.
A couple of suggestions. Set the seat back as far as you can and raise the handlebars significantly.
Something that's counterintuitive is that some people find it more comfortable to stretch out their reach to the bars rather than bringing the bars close when they feel like there is too much weight on their hands.
There's definitely a communication problem going on, and personally I would have asked a LOT of questions first before specifying a 76 degree seat tube angle, however if you achieve KOPS and aren't in front of KOPS, then the builder isn't necessarily wrong.
08-20-22, 08:17 AM
#23
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Another measurement to assess.
How much distance is there measured from the tip of the saddle nose forwards to a vertical line up from the centre of the bottom bracket?
Place a rule from the tip of the saddle towards the head tube, and drop a plumb bob down to cross the centre of the BB.
Measure at standard saddle height, this is important.
5cm setback or a little more would be reasonable. If the saddle nose is in front of the BB then that's definitely too steep.
How much distance is there measured from the tip of the saddle nose forwards to a vertical line up from the centre of the bottom bracket?
Place a rule from the tip of the saddle towards the head tube, and drop a plumb bob down to cross the centre of the BB.
Measure at standard saddle height, this is important.
5cm setback or a little more would be reasonable. If the saddle nose is in front of the BB then that's definitely too steep.
Last edited by AnthonyG; 08-20-22 at 08:38 AM.
08-20-22, 11:56 AM
#24
Banned.
So many complicated factors to this fit issue.
On the face of it, 76 degrees does sound quite steep and I usually recommend much slacker seat tube angles.
However, If you can position yourself to KOPS, and your not way in front of KOPS, then on paper, the builder has built the frame correctly, not withstanding that KOPS isn't the be all and end all of everything.
Now I don't want to be rude, but are you overweight?
Bicycles are just not comfortable, and they never will be for overweight riders. There always will be too much weight on your hands/arms/shoulders if you are overweight.
Catch 22 here I know.
A couple of suggestions. Set the seat back as far as you can and raise the handlebars significantly.
Something that's counterintuitive is that some people find it more comfortable to stretch out their reach to the bars rather than bringing the bars close when they feel like there is too much weight on their hands.
There's definitely a communication problem going on, and personally I would have asked a LOT of questions first before specifying a 76 degree seat tube angle, however if you achieve KOPS and aren't in front of KOPS, then the builder isn't necessarily wrong.
On the face of it, 76 degrees does sound quite steep and I usually recommend much slacker seat tube angles.
However, If you can position yourself to KOPS, and your not way in front of KOPS, then on paper, the builder has built the frame correctly, not withstanding that KOPS isn't the be all and end all of everything.
Now I don't want to be rude, but are you overweight?
Bicycles are just not comfortable, and they never will be for overweight riders. There always will be too much weight on your hands/arms/shoulders if you are overweight.
Catch 22 here I know.
A couple of suggestions. Set the seat back as far as you can and raise the handlebars significantly.
Something that's counterintuitive is that some people find it more comfortable to stretch out their reach to the bars rather than bringing the bars close when they feel like there is too much weight on their hands.
There's definitely a communication problem going on, and personally I would have asked a LOT of questions first before specifying a 76 degree seat tube angle, however if you achieve KOPS and aren't in front of KOPS, then the builder isn't necessarily wrong.
I would think anyone who gets more comfortable stretching out their reach to unload their arms is actually using their arms mostly to support their upper body weight which is wrong due to causing numb hands. The right way is using your back to support that weight so the arms are mostly unloaded.
If you turn out right about their weight, setting the seat all the way back on a setback seatpost can be risky. The adjustment can break the seatpost in a hard bump or worse, damage the frame
08-20-22, 12:37 PM
#25
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Actually, there has been a trend in the last few years with MTB frames, even non-custom ones, being designed with 77-79 degree STA, so that may be what this builder was going by. I don't understand that concept either. (Believe the theory is that it allows you to climb very steep hills better.) I have a 91cm inseam, and if the tip of my saddle is less than 10cm behind the BB, not only does my speed/power drop sharply -- even up a steep hill -- but my thighs, knees, and hands start hurting, so I know, at least for me, those steep STAs are completely wrong.