Burning thighs on road bike (but not on TT bike)

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Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

Hi all,
I wonder if anybody has experienced the same and/or knows how to fix the following:
On my roadbike i have burning/blocked upper thighs (all over) and glutes when increasing power. It feels like my muscles are suffocating and cant keep pressure. Increasingly to the point that i cant even stand on the bike anymore. Around and below ''ftp'' my legs already start to block, but the worst is in the higher zones. I have been checked for arterial problems and all other kind of stuff, they did find poor blood circulation/lactic acid clearance from the muscles, but no causes or whatever. I tried physio's and everything but so far nothing has brought complete relief.
The weird thing is that on my TT bike I dont suffer from this issue and feel amazing on high power, with no burning thighs at all. For example i managed to do 430watts on 20min on tt bike and barely 400 on the roadbike with the same powermeter. Also in the higher zones, on my tt bike i can endure the increasingly burning legs, and on the roadbike its immediately unbearable.
Ive had bikefits for both bikes multiple times, but everybody says i should not change my position on my road bike towards my tt bikefit since it would only give me problems. The difference between the two bikes is the saddle of the tt bike being 15mm higher, and 30mm more forward.
Has anyone experienced this and or fixed this? I’ve had this for four years and I never found any answers. It comes to the point that racing on the roadbike is not fun anymore because it feels like im half as strong as on the TT bike

by Weenie


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Maddie
Posts: 1532
Joined: Tue Oct 17, 2017 5:44 am

by Maddie

If you had this for four years, why didn't you ever change your saddle position? Maybe 5mm change and 10mm setback at the same time and see how it goes. You've got nothing to lose and you can always revert to your old position.

Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

As its quite far forward, my saddle already is on the max forward position. There are no zero offset seatposts, so the only option would be adjusting the seatpost for 250euros. Also every bikefitter says going more forward only would yield more problems, so thats why i havent done it yet..

Andrew69
Posts: 593
Joined: Thu Feb 19, 2009 10:52 am
Location: ɹǝpunuʍop

by Andrew69

Very weird issue as most people are weaker on their TT vs road bike.

Need more information, but I know I have similar issues if my saddle is too far forward on my roadie
For me at least, there is an optimal setback behind the bottom bracket where I can engage quads/hammies and glutes.
Too far either way (backwards or forwards) and one muscle group suffers as does my power

Need to know your saddle height, effective seat tube angle and saddle setback (from bb) as well as crank lengths to see if there is anything obvious.

Seen too many people over the years buy a bike that is too long for them and then they compensate by simply pushing the saddle forward without thinking of the consequences of power delivery and muscle recruitment

poulhansen
Posts: 298
Joined: Wed Nov 25, 2020 12:49 pm
Location: Danmark

by poulhansen

"for years" Why trust those gurus? You are having problems NOW so do try another position, even if they are right, maybe the new problems are less than the current one. And as already said, adjust the saddle maybe in increments, it takes 10 minutes.

I have zero offset seatpost, although they are round, so I don't know if they suit your bike.

"my saddle already is on the max forward position" Sounds like the frame is too big or your stem is too long.

I normally need 54 cm frames but have successfully adopted 56 cm frames by change saddle height/position and stem length, so they correspond exactly to my "standard bike" (I always buy used or vintage bikes, so you can't always choose)
Cannondale Super Six HiMod 2017 6.7 kg
Cannondale six13, 2004, 5.50kg
Focus Izalco Max, 2023 4.418 kg

Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

Andrew69 wrote:
Mon Apr 17, 2023 6:15 am

Need more information, but I know I have similar issues if my saddle is too far forward on my roadie
For me at least, there is an optimal setback behind the bottom bracket where I can engage quads/hammies and glutes.
Too far either way (backwards or forwards) and one muscle group suffers as does my power

Need to know your saddle height, effective seat tube angle and saddle setback (from bb) as well as crank lengths to see if there is anything obvious.
I tried a lot with changing crank length. I went from 175 to 165. First on my roadbike and now also on my tt bike. On the TT bike it feels great and I dont see any reason change it. On the roadbike in the accelerating nature of a race and my relatively low cadance i felt like 165 was too short as my cadance did not increase. I am now on 170's on my roadbike and its better than 175's for sure.

Recommended sizes for the fit were: saddle height 813mm and setback 86mm. I dont know effective seattube angle, but the frame is @73degrees and the post is 10mm setback.

Like i said like that i felt i was never really planted in the saddle and always sliding forward feeling like i needed to support my weight with my thighs instead of just pedaling the pedals only.
Also I dont feel comfortable at high cadance at all, the sliding sensation becomes worse and my butt and all over my thighs start to block. At low cadance it's way more manageable but I used to be very good at high cadance and now i basically cannot be in the high power zones for longer time above 95RPM. I train it a lot, but its just not improving.

I put the forward part of my saddle level (used to be nose up otherwise the sliding forward and levating over the saddle feeling at hard efforts was really bad), raised my seat to 820mm and shortened the setback to saddle all the way forward at 78mm. From what I'm reading i should either try pulling it forward to tt ranges: 55-65mm behind BB or like wayway behind since 2/3mm is not making any difference.

Saddle to bar drop and everything is not extreme at all, even more I think I would maybe even feel more planted in the saddle if my bar would be lower, because i'd need to rotate forward more.

Right now when the pace is high in races my glute medius starts to block, and my legs feel like theyre being strangled. Ive been to a vascular surgeon and everything looks healthy, at the physio were trying to get the glutes and hamstring stronger. This helps but i feel like the real solution would be in the fit on my bike since I'm so strong on the TT bike already and so blocked on the road bike.

Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

poulhansen wrote:
Mon Apr 17, 2023 12:08 pm
"my saddle already is on the max forward position" Sounds like the frame is too big or your stem is too long.
I think normally it would have been fine as of people my length ride a setback in between 80-100mm i think. If i want to approach my TT fit (55mm, saddle all the way forward) I indeed need to look for a zero offset post in my aeroframe and even then it needs to be all the way forward since the bike has a relatively relaxed seat tube angle. For my length 188cm, I have a size 56 frame, with a 12cm stem. It's the same reach as my previous bike had before the problems started so I don't think the reach of the bike should be a problem.

bmrk
Posts: 185
Joined: Sat Feb 18, 2023 4:03 pm

by bmrk

Gunter wrote:
Mon Apr 17, 2023 6:04 pm
Andrew69 wrote:
Mon Apr 17, 2023 6:15 am

Need more information, but I know I have similar issues if my saddle is too far forward on my roadie
For me at least, there is an optimal setback behind the bottom bracket where I can engage quads/hammies and glutes.
Too far either way (backwards or forwards) and one muscle group suffers as does my power

Need to know your saddle height, effective seat tube angle and saddle setback (from bb) as well as crank lengths to see if there is anything obvious.
I tried a lot with changing crank length. I went from 175 to 165. First on my roadbike and now also on my tt bike. On the TT bike it feels great and I dont see any reason change it. On the roadbike in the accelerating nature of a race and my relatively low cadance i felt like 165 was too short as my cadance did not increase. I am now on 170's on my roadbike and its better than 175's for sure.

Recommended sizes for the fit were: saddle height 813mm and setback 86mm. I dont know effective seattube angle, but the frame is @73degrees and the post is 10mm setback.

Like i said like that i felt i was never really planted in the saddle and always sliding forward feeling like i needed to support my weight with my thighs instead of just pedaling the pedals only.
Also I dont feel comfortable at high cadance at all, the sliding sensation becomes worse and my butt and all over my thighs start to block. At low cadance it's way more manageable but I used to be very good at high cadance and now i basically cannot be in the high power zones for longer time above 95RPM. I train it a lot, but its just not improving.

I put the forward part of my saddle level (used to be nose up otherwise the sliding forward and levating over the saddle feeling at hard efforts was really bad), raised my seat to 820mm and shortened the setback to saddle all the way forward at 78mm. From what I'm reading i should either try pulling it forward to tt ranges: 55-65mm behind BB or like wayway behind since 2/3mm is not making any difference.

Saddle to bar drop and everything is not extreme at all, even more I think I would maybe even feel more planted in the saddle if my bar would be lower, because i'd need to rotate forward more.

Right now when the pace is high in races my glute medius starts to block, and my legs feel like theyre being strangled. Ive been to a vascular surgeon and everything looks healthy, at the physio were trying to get the glutes and hamstring stronger. This helps but i feel like the real solution would be in the fit on my bike since I'm so strong on the TT bike already and so blocked on the road bike.

You are feeling the need to do low cadence and gravitate towards the nose of the saddle to support your weight and you increase your saddle height?

Whats the your inseam size?

Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

bmrk wrote:
Mon Apr 17, 2023 7:26 pm

You are feeling the need to do low cadence and gravitate towards the nose of the saddle to support your weight and you increase your saddle height?

Whats the your inseam size?
I feel that when i lower it, I'm supporting/carrying my weight even more when biking hard, like a wallsit. When I put the saddle higher i feel more like I'm hanging in the saddle, only having to focus on pedaling with no additional pressure on my thighs. But if i put my saddle as high on my road bike as on my tt bike, logically my lowerback hurts and i feel stiff.
Inseam is 92.6cm

bmrk
Posts: 185
Joined: Sat Feb 18, 2023 4:03 pm

by bmrk

Gunter wrote:
Mon Apr 17, 2023 9:34 pm
bmrk wrote:
Mon Apr 17, 2023 7:26 pm

You are feeling the need to do low cadence and gravitate towards the nose of the saddle to support your weight and you increase your saddle height?

Whats the your inseam size?
I feel that when i lower it, I'm supporting/carrying my weight even more when biking hard, like a wallsit. When I put the saddle higher i feel more like I'm hanging in the saddle, only having to focus on pedaling with no additional pressure on my thighs. But if i put my saddle as high on my road bike as on my tt bike, logically my lowerback hurts and i feel stiff.
Inseam is 92.6cm
At the 813mm saddle height which is the drop to the handlbars? Also, how are your cleats positioned?

by Weenie


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Gunter
Posts: 6
Joined: Sun Apr 09, 2023 10:04 pm

by Gunter

bmrk wrote:
Mon Apr 17, 2023 10:06 pm


At the 813mm saddle height which is the drop to the handlbars? Also, how are your cleats positioned?
12cm, honestly I feel like it could be deeper, the feeling in my legs are not really connected to bar height. I somehow do feel when i higher the bar, i have less pressure in the saddle and feel less seated even more.
Cleats are done by the bikefitter, exactly under the metarsal head of the foot. Also I wear the same shoes on my tt bike, and then it does work for me..

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