Do smaller sized handlebars effect handling?

[wc1934]

40cm is my normal handlebar width.

I tried riding 42 as an experiment (for me, the wider bar did not offer an improvement in breathing capacity).

I then tried a 40cm fsa compact wing pro which actually measures closer 38. These bars seemed to dramatically change the handling of the bike - very twitchy - and standing while riding with one hand was challenging. Was it my imagination, or do smaller sized bars effect handling?

The head tube angle on my bike is 71 degrees and HT length is 14cm.
Do these get added to the stability equation?

[prototoast]

The further the handlebar puts your hand from the steering axle, the more your hand has to move to steer, and vice versa. So yes, they do affect steering, though in my experience the effect is usually fairly small--for example, going from a 42 to a 38 is a much smaller change than going from the goods to the tops, which I regularly do.

Another potential issue is you may have overtightened the headset when you switched bars. Any overly tight headset makes a bike feel twitchy.

[m_sasso]

40cm is my normal handlebar width.

I tried riding 42 as an experiment (for me, the wider bar did not offer an improvement in breathing capacity).

I then tried a 40cm fsa compact wing pro which actually measures closer 38. These bars seemed to dramatically change the handling of the bike - very twitchy - and standing while riding with one hand was challenging. Was it my imagination, or do smaller sized bars effect handling?

The head tube angle on my bike is 71 degrees and HT length is 14cm.
Do these get added to the stability equation?

Yes, bar width will affect handling. The further away you move a lever from the centre of rotation the larger that movment needs to be to have the same affect.

[robt57]

Do smaller sized handlebars effect handling?

Unequivocally.

[zmudshark]

Unequivocally.

indubitably.

[Ken Robb]

Wider bars and/or longer stems tend to slow steering a bit.

[madsciencenow]

Was the reach the same on all the bars? Seems like that could a factor as well?


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[charliedid]

Yes

You can stand and pedal and have just one hand on the bar? I'm not sure I could do that...

[wc1934]

Yes

You can stand and pedal and have just one hand on the bar? I'm not sure I could do that...

Sorry for the misleading statement - I am not pedaling. Just standing/coasting with one hand off the bar - usually adjusting my bibs - haha

[charliedid]

Sorry for the misleading statement - I am not pedaling. Just standing/coasting with one hand off the bar - usually adjusting my bibs - haha

Haha okay good, I didn't want to feel compelled to try that as I know it would end badly.

[Blue Jays]

My preference is for narrower bars. Just a comfort thing. They are typically Ritchey bars and stems.

[wc1934]

Haha okay good, I didn't want to feel compelled to try that as I know it would end badly.

haha - I hear ya. I've always wanted to be like Marco and climb standing while in the drops.

[fogrider]

40cm is my normal handlebar width.

I tried riding 42 as an experiment (for me, the wider bar did not offer an improvement in breathing capacity).

I then tried a 40cm fsa compact wing pro which actually measures closer 38. These bars seemed to dramatically change the handling of the bike - very twitchy - and standing while riding with one hand was challenging. Was it my imagination, or do smaller sized bars effect handling?

The head tube angle on my bike is 71 degrees and HT length is 14cm.
Do these get added to the stability equation?

One ride? I don't think that's a fair test. give it a couple of rides. With road bikes, you really don't steer by turning the bars, you lean the bike. But the human body and fit is an odd thing, some people can adapt...some can, but it takes time.

[marciero]

Yes

You can stand and pedal and have just one hand on the bar? I'm not sure I could do that...

I do this sometimes when climbing out of the saddle in order to wave to acknowledge a motorist who has afforded me some courtesy- typically letting me pass through an intersection- and I dont want to slow down. Not hard once you get used to a sort of undulating motion with your upper body. OTOH I cant even do a track stand

[Dave]

Many people don't realize it but a bicycle is steered with the bars, just like a motorcycle. The bike will lean to the right and turn right if you counter steer by pushing on the right side of the bars. The big difference is the small amount of force required, compared to a motorcycle.

The steering arm length is a straight line between the point of hand contact with the bars or brake hoods and the center of the steering tube. Reducing the bar width, the bar reach or the stem length will all shorten the steering arm length.

It should only take a ride or two to get used to a change to the steering arm. No small change should ever make a bike difficult to steer or negatively impact handling.

I've had two of the same bike and used 38cm bars on one and 40cm on the other. It didn't bother the handling a bit. I did decide that the 38cm better fit my shoulder width and eventually changed to that size on both bikes.

[marciero]

Many people don't realize it but a bicycle is steered with the bars, just like a motorcycle. The bike will lean to the right and turn right if you counter steer by pushing on the right side of the bars. The big difference is the small amount of force required, compared to a motorcycle.



In fact countersteering is the only way to initiate a turn, no matter what your body sensations are telling you. The only difference is that consciously doing it helps some riders corner more aggressively, more smoothly, etc.

[d_douglas]

I am a big guy and when I heard 46cm bars were a thing, I went all out. Then I tried someone’s 44cm and realized the change is very minor plus they aren’t so ungainly as they 46cm.

It’s a matter of preference, but I cannot imagine using a 42cm at my size, yet I know tons of people do. I guess 44cm is my sweet spot.

[carpediemracing]

If you're riding one handed with your hand next to the stem, bar width won't matter. Holding the bar next to the stem is the most stable way to ride one handed since it limits accidental input to the bars. It's why track racers slinging their partner into the race will hold the center of the bars. (The racer being slung into the race will hold the drop only because they are racing 100% as soon as they're in the race, plus the rider doing the slinging does most of the slinging work.)

It's also why it's stable on smooth roads to descend in a tuck while holding the tops - limits input to the bars. But on rough roads, where you need to make sure the wheel doesn't turn sideways, holding the drops has benefits (resists lateral wheel movement better).

When riding one handed on the drops or hoods, a narrower bar will feel twitchier because the same amount of input (1 cm push forward, for example) will turn the front wheel proportionately more. Therefore what you thought of as "fine motor inputs" become "coarse motor inputs".

If riding normally then you'll probably adjust pretty quickly. More awkward maneuvers, like coasting while standing while holding just one hood or drop... that might take some focused practice. However you can always just move your hand to the center of the bars.

[benb]

Almost every one of these effects a bar/stem change has is balanced out by something else that can make a lot of it a wash when you fully look at the physics.

Wider bars - you do have to move your hands further for the same wheel rotation.. but the wider bars provide more leverage, so you'll use less force to move the bar, which balances everything out.

Longer stem - requires moving the handlebars further.. but provides more leverage against the steering column.

You can adjust to all this stuff really quickly within a ride. But if a specific configuration places your body in an uncomfortable position you can't necessarily adjust to that as easily, and if the changes shifts your body weight that can have a larger effect than anything else.

[pdonk]

I had always thought I was a "bigger" person and needed 44cm bars. For reference, I wear a 43 or 44 sized suit.

When i had my fitting, I was set up on 40s and 40s came with my bike. Now after nearly 2 years on the 40s, I like them. Whenever I ride my bike with 44s they seem huge and just feel off.

I think I'd like to try 42s for a just a bit more space, but doubt I will, until my enves need to be replaced.

[haruharu]

I had always thought I was a "bigger" person and needed 44cm bars. For reference, I wear a 43 or 44 sized suit.

When i had my fitting, I was set up on 40s and 40s came with my bike. Now after nearly 2 years on the 40s, I like them. Whenever I ride my bike with 44s they seem huge and just feel off.

I think I'd like to try 42s for a just a bit more space, but doubt I will, until my enves need to be replaced.

During my bike fit, I was told to up to a 42cm from a 40cm to increase my functional respiratory capacity. But I measured my drops and it seems my tops is 40 and drops is 42cm.

In your case did you ever noticed a difference in breathing rate or depth?

[marciero]

Almost every one of these effects a bar/stem change has is balanced out by something else that can make a lot of it a wash when you fully look at the physics.

Wider bars - you do have to move your hands further for the same wheel rotation.. but the wider bars provide more leverage, so you'll use less force to move the bar, which balances everything out.

Longer stem - requires moving the handlebars further.. but provides more leverage against the steering column.


This is true regarding the wider bars. As far as longer stem- that is probably going to be negligible because you would be moving your hands closer to tangentially than radially. For big differences, for example at the extremes with a very short stem with wide flat bars vs long stem and narrow drop bars, the difference in feel will have to do less with force and leverage than the movement of your hands. The former case is like having your hands at 9:00 and 3:00 on a steering wheel. In the latter case, not only is it more like 10 and 2 or 11 and 1. In the latter case the movement of your hands is more side to side.

In my experience this is all swamped by the simple feel of having your hands closer together or farther apart. It simply feels strange to have hands closer together than I am used to and is much more noticeable than a change in handling. Regarding stem length-since I use long reach bars changing the stem length simply changes what part of the bar I spend more time on and not where they are in relation to the steering column so will not affect handling in any way related to leverage or angle of rotation

[marciero]

During my bike fit, I was told to up to a 42cm from a 40cm to increase my functional respiratory capacity. But I measured my drops and it seems my tops is 40 and drops is 42cm.

In your case did you ever noticed a difference in breathing rate or depth?

That was the old argument, circa 1990? something like that. I dont think there is evidence to support it. In any case, flared bars (and probably any number of other adjustments) would achieve the same effect by moving elbows outward

[m_sasso]

That was the old argument, circa 1990? something like that. I dont think there is evidence to support it. In any case, flared bars (and probably any number of other adjustments) would achieve the same effect by moving elbows outward

Thank you, I was beginning to think I was back in 1985, sometimes there is so much ill conceived information on the internet it is difficult for new riders to find what is current, proven and correct.

One of the biggest aero differences a road rider can make is utilizing narrow handlebars.