How much should an handlebar flex?
#1
Senior Member
Thread Starter
Join Date: Mar 2016
Location: South Italy
Posts: 849
Bikes: BMC SLR01; Cannondale Trail; Robur 1956 ; Tomasini 1976 ; Chiorda Condorino 1974 ; Frejus/Rola 1937 ; Specialized RockHopper 1990
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 246 Post(s)
Liked 132 Times
in
81 Posts
How much should an handlebar flex?
I was looking some review regarding an handlebar and a guy replied me on YouTube that the handlebar He's using is flexing about 5-8mm (the rider weight 80kg and the riding type is aggressive).
How much should a carbon handlebar flex in a normal conditions?
Assuming an high output of watts for example in a final sprinting, how much should an handlebar flex?
maybe the tread is very stupid but for me those millimeters of flexing is abnormal.
How much should a carbon handlebar flex in a normal conditions?
Assuming an high output of watts for example in a final sprinting, how much should an handlebar flex?
maybe the tread is very stupid but for me those millimeters of flexing is abnormal.
#2
Habitual User
Join Date: Jan 2020
Location: Altadena, CA
Posts: 5,489
Bikes: 2019 Trek Procliber 9.9 SL, 2018 Storck Fascenario.3 Platinum, 2017 Bear Big Rock 1, 2003 Time VX Special Pro, 2001 Colnago VIP, 1999 Trek 9900 singlespeed, 1977 Nishiki ONP
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 3346 Post(s)
Liked 5,351 Times
in
2,525 Posts
In the days when I was racing at the peak of my fitness, and putting out a lot of watts in a sprint, I preferred a stiff CF handlebar. It probably was flexing, but I didn't ever want to feel that flex in my hands, in those conditions. I'm not doing any max-effort sprinting these days, but I still prefer a firm handlebar feel on my road bike, during hard efforts.
My gravel bike, however, is different. I prefer a little bit of compliance.
I probably didn't answer your question at all.
My gravel bike, however, is different. I prefer a little bit of compliance.
I probably didn't answer your question at all.
__________________
"Swedish fish. They're protein shaped." - livedarklions
"Swedish fish. They're protein shaped." - livedarklions
#3
Senior Member
Thread Starter
Join Date: Mar 2016
Location: South Italy
Posts: 849
Bikes: BMC SLR01; Cannondale Trail; Robur 1956 ; Tomasini 1976 ; Chiorda Condorino 1974 ; Frejus/Rola 1937 ; Specialized RockHopper 1990
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 246 Post(s)
Liked 132 Times
in
81 Posts
In the days when I was racing at the peak of my fitness, and putting out a lot of watts in a sprint, I preferred a stiff CF handlebar. It probably was flexing, but I didn't ever want to feel that flex in my hands, in those conditions. I'm not doing any max-effort sprinting these days, but I still prefer a firm handlebar feel on my road bike, during hard efforts.
My gravel bike, however, is different. I prefer a little bit of compliance.
I probably didn't answer your question at all.
My gravel bike, however, is different. I prefer a little bit of compliance.
I probably didn't answer your question at all.
this let me think
#4
Habitual User
Join Date: Jan 2020
Location: Altadena, CA
Posts: 5,489
Bikes: 2019 Trek Procliber 9.9 SL, 2018 Storck Fascenario.3 Platinum, 2017 Bear Big Rock 1, 2003 Time VX Special Pro, 2001 Colnago VIP, 1999 Trek 9900 singlespeed, 1977 Nishiki ONP
Mentioned: 5 Post(s)
Tagged: 0 Thread(s)
Quoted: 3346 Post(s)
Liked 5,351 Times
in
2,525 Posts
Part of my thinking was that I didn't want any of my power lost to flexing parts. I don't know how much of that is a real concern, but that was my thought. In reality, there was probably a lot more flex than I was aware of.
__________________
"Swedish fish. They're protein shaped." - livedarklions
"Swedish fish. They're protein shaped." - livedarklions
Likes For Eric F:
#5
Senior Member
Join Date: May 2022
Location: USA
Posts: 1,777
Bikes: Cannondale - Gary Fisher - Giant - Litespeed - Schwinn Paramount - Schwinn (lugged steel) - Trek OCLV
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 812 Post(s)
Liked 817 Times
in
526 Posts
how much flex in normal conditions ?
depends on a few variables
interesting read on road handlebar testing :
https://blog.fairwheelbikes.com/revi...dlebar-review/
a little dated - but still good read
depends on a few variables
interesting read on road handlebar testing :
https://blog.fairwheelbikes.com/revi...dlebar-review/
a little dated - but still good read
Likes For t2p:
#6
Senior Member
Join Date: May 2022
Location: USA
Posts: 1,777
Bikes: Cannondale - Gary Fisher - Giant - Litespeed - Schwinn Paramount - Schwinn (lugged steel) - Trek OCLV
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 812 Post(s)
Liked 817 Times
in
526 Posts
lightweight handlebar - and a little ‘flexy’ ... could feel it when you were out of the saddle (especially compared to standard Cinelli handlebar or whatever)
sprinter like you prob would not like this handlebar - but for me it was prob a good thing ... small guy on a stiff Cannondale
#7
Senior Member
Join Date: Jun 2002
Location: San Jose, CA
Posts: 3,267
Bikes: Too many bikes, too little time to ride
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 289 Post(s)
Liked 230 Times
in
185 Posts
how much flex in normal conditions ?
depends on a few variables
interesting read on road handlebar testing :
https://blog.fairwheelbikes.com/revi...dlebar-review/
a little dated - but still good read
depends on a few variables
interesting read on road handlebar testing :
https://blog.fairwheelbikes.com/revi...dlebar-review/
a little dated - but still good read
#8
Senior Member
The more the better, for me as a recreational rider. I seek out flexier bars for all my biking- road, Mtn, gravel, and fat snow.
#9
Doesn't brain good.
Join Date: Jun 2015
Location: Pacific Northwest
Posts: 2,551
Bikes: 5 good ones, and the occasional project.
Mentioned: 20 Post(s)
Tagged: 0 Thread(s)
Quoted: 1411 Post(s)
Liked 1,165 Times
in
669 Posts
I can confirm that the FSA Kwing is indeed very flexy. I'd venture to say the point of being too much.
I have 2 obtained at various times under different circumstances.
The first was used on a single ride. Vague, and disconnected are words I would use to describe it. I basically removed it the moment I walk through the door after returning from the ride.
The second bar is on a gravel bike. It completely sucks the life out of the bike in a general sense but it does indeed smooth out rough terrain. On that bike I am squarely undecided. It would shine on cobbles.
I'd say the Kwing is suited to much stiffer rides than I own.
Too much of anything isn't always a good thing.
I have 2 obtained at various times under different circumstances.
The first was used on a single ride. Vague, and disconnected are words I would use to describe it. I basically removed it the moment I walk through the door after returning from the ride.
The second bar is on a gravel bike. It completely sucks the life out of the bike in a general sense but it does indeed smooth out rough terrain. On that bike I am squarely undecided. It would shine on cobbles.
I'd say the Kwing is suited to much stiffer rides than I own.
Too much of anything isn't always a good thing.
#10
Senior Member
Join Date: Dec 2019
Location: 757
Posts: 8,386
Bikes: Madone, Emonda, 5500, Ritchey Breakaway
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 7569 Post(s)
Liked 3,582 Times
in
1,538 Posts
I have never noticed any flexing on the cervelo carbon bars or the madone slr cockpit. I was never lookin though, didn’t realize that was an issue. I was told to stay away from the amazon bars because they flex a lot. I almost feel like that would be nerve racking if my bars were flexing in a sprint.
#11
climber has-been
Join Date: Dec 2004
Location: Palo Alto, CA
Posts: 5,855
Bikes: Scott Addict R1
Mentioned: 10 Post(s)
Tagged: 0 Thread(s)
Quoted: 2328 Post(s)
Liked 2,312 Times
in
1,171 Posts
I have never noticed any flexing on the cervelo carbon bars or the madone slr cockpit. I was never lookin though, didn’t realize that was an issue. I was told to stay away from the amazon bars because they flex a lot. I almost feel like that would be nerve racking if my bars were flexing in a sprint.
I'd be more concerned about turning on a descent. Hitting a hole or bump during a turn might be disconcerting, as the bars would suddenly flex.
__________________
Ride, Rest, Repeat
Ride, Rest, Repeat

#12
bike whisperer
Join Date: Dec 2009
Location: Melbourne, Oz
Posts: 9,504
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 1505 Post(s)
Liked 704 Times
in
499 Posts
The flex only slows you down if there's significant hysteresis associated with it, ie if it doesn't return almost all the energy into the system when it unflexes. And if it saves you energy by isolating you from harshness, you'll be faster over long distances.
__________________
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
#13
bike whisperer
Join Date: Dec 2009
Location: Melbourne, Oz
Posts: 9,504
Bikes: https://weightweenies.starbike.com/forum/viewtopic.php?f=10&t=152015&p=1404231
Mentioned: 15 Post(s)
Tagged: 0 Thread(s)
Quoted: 1505 Post(s)
Liked 704 Times
in
499 Posts
To my mind, that's probably more likely to work for you than against you - suspension is good for grip.
__________________
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
Sheldon Brown's bike info ~~~ Park Tools repair help
Half-step triple, using double gear ~~~ 6400 STI rebuild walkthrough ~~~ Want 8/9/10s @126mm OLD? OCR. ~~~ Shimano cassette body overhaul ~~~ Ergopower Escape wear repair ~~~ PSA: drivetrain wear
List of US/Canada bike co-ops ~~~ Global list
#14
Senior Member
Join Date: Aug 2004
Location: Prague, Czech Republic
Posts: 2,736
Bikes: Merlin Extra Light, Orbea Orca, Ritchey Outback,Tomac Revolver Mountain Bike, Cannondale Crit 3.0 now used for time trials.
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 121 Post(s)
Liked 48 Times
in
31 Posts
I remember my old Lemond Drop In (Scott I think) from the early 1990s. Super flexy and to my mind back then, this was good for increased comfort. Now, the Ritchey WCS alloy bars that I use are dead stiff as are the 3T carbon bars on another bike; no complaints and a prefered feel for me.