car5car

I used to ride Chinese bike with 20" seat tube, but the tube is not a problem, I felt wheelbase was too short. Seat tube is not important, wheelbase is, I think. Some of my motorcycles were too short.

Iride01 

The wheel base will be what ever it is the designers of the bike made it for what ever size that is suggested for you in that particular model.

Wheel base can make some differences to your perception about the bike. But Trail is another thing you need to look at too and maybe even the head tube angle and fork rake. All contribute to how you'll perceive the handling. Shorter wheelbase, less trail and the bike might seem twitchier than a similar bike with longer wheel base and more trail. However other people might think of what one perceives as twitchy are being quicker maneuvering or sporty. I like sporty.

You can't really make a blanket statement though. You just need to get on it and ride it to see for yourself. There are other things that will affect your perception of how the bike handles. So one thing going toward the direction of sporty may not actually make the bike sporty. Nor will a longer wheel base necessarily be more stable and luxurious.

Kontact

Wheelbase controls cornering radius. Not a lot beyond that. Not a fit topic.

car5car

Seat tube doesn't matter, tall rider can install longer seat post. Wheel base really matters. Motorcycle specs include wheelbase.

Kontact

So you'll have to tell us: What is it about bicycle wheelbase that causes you a problem with fit? You don't sit on the wheels."Fit" refers to how your body interacts with the three points of contact - the bars, seat and pedals.

The overall geometry of the bike dictates both fit and handling. Wheelbase is a handling related geometry number.

car5car

I had same problem with bikes and motorcycles:
I felt that if I use front brake too hard, I will flip forward. At some point I started checking motorcycle wheelbase specs before buying them: 55" was too short, over that was OK, 62" was very comfortable.

ThermionicScott 

Short wheelbase is usually considered a virtue by sporty riders, even the tall ones. If you want something different, you'll have to shop for it.

79pmooney

Wheelbase is what you get after setting the front center and the chainstay length. Sounds like what you do not like is bikes with short front centers. (Distance BB to front hub.)

You could measure the BB to hub distance on a bike you like and use that to judge future bikes.

base2 

Some people confuse quick, light handling provided by a lot of rake/a minimum of trail to be the result of a short wheelbase.

OP: If the bike feels too nimble, try swapping for a fork of the same axle to crown height but less rake. The result will be more trail. Which means the ground passing by underneath will exert a stronger handlebar straightening effect.

himespau 

Shop for touring bikes?

PeteHski

More trail does indeed increase steering weight and stability as a single parameter. But that doesn't mean that a steeper head angle/short wheelbase is good for stability. What you really want for maximum stability is both a slacker head angle AND increased trail, which can be achieved with the appropriate fork offset. Modern mountain bikes are a perfect example of this appication and we see it to a lesser degree in gravel bikes.

Kontact

On road bikes, at least, stability and steering responsiveness is almost entirely trail. I have ridden bikes with as little as 71 and as great as 73.5 head tube angles, and if the trail was the same, it was very hard to notice any difference between them. And long trail is only stable at higher speeds. At low speeds it makes the steering ponderous, making it harder to ride hands off. Merckx preferred low trail bikes because they were easier to keep straight on cobbles. Most American builders prefer neutral trail.


The OP believes short wheelbases are going to cause the bike to flip. I think most cyclists realize that isn't an entirely rational fear. However, it isn't the wheelbase that would make you more likely to flip but the front center - the distance between the crank and the front wheel. On a bicycle, a long rear end imparts almost no mass to keep the back end from coming off the ground.

himespau 

Maybe better brake distribution between front and rear would help.

Iride01 

The entire geometry of the bike still has as much to say about whether a bike will do that or not. You still can't go by just one spec such as wheel base and make that broad statement for all.

And you are saying that you "felt" that would happen. Did you ever come close? Or is it just that maybe you aren't use to riding road bikes with your body leaned forward and your head in front of everything? That might take some time getting use to if you are use to sitting very upright.

I had one bike that the rear wheel would come off the ground when doing a panic stop on a down hill section of road. It was a bigger size frame than my current bike which doesn't exhibit that issue. Nor have I ever had that issue with any other road bike I've owned.

You learn quickly to address such issues if you have them. I learned that all I had to do was simply slide my butt as far back to the rear of the saddle when do such quick stops on downhills and it wasn't ever a safety issue for me.

Don't let your obsession with one dimension out of all the other geometry specs keep you from trying out a bike and seeing if it is the bike for you.

base2 

Indeed.
I was responding from the perspective of the OP already owned a bike & didn't like or mis-appropriated some aspect of the handling. As a single factor that can be changed is the fork length (affecting HTA) & the rake of the fork.

You are most definitely correct, with the added caveat that at some point with too much of either (both,) too much flop becomes a concern & greater leverage over the steering axis is needed to counter the rise/fall caused by too much head-tube angle. Shorter stems to put wider bars in reach to exert control over all that stability is/was inevitable.

Still, while wheelbase is a factor like the OP rightly believes, it is not a driving factor in handling (maneuverability.) Even then, the riders weight distribution along that wheelbase determines utility. Hence front-center/rear-center being more important than total wheelbase but still being the secondary to rake/trail et.al.

Wheelbase is perhaps one of the least important metrics in terms of handling/maneuverability. I like to think wheelbase is more strongly related to a bikes "personality" than any other combination of data points. A longer bike is going to track much straighter for a given steering deviation than a short bike. Think of the contact patch of the rear wheel acting like the tail feathers on an arrow & you'll see what I mean.

Anecdote of one:
I have a custom bike with 20 inch (505mm) chain-stays. And a total wheelbase of 1170mm. I wanted it to be stable while speeding down mountain passes while heavily loaded. The 62mm of trail afforded by 26x2.3 tires and the weight being a long ways behind the steering means that the bike can accept higher loads with proportionally less effect on distribution. Predictable is a word I would use to describe it.

When unloaded & configured with 559x32 tires the trail is ~55-56-ish. It rides exceptionally straight, light handling. The term "surgical precision" comes to mind every time I ride it. Like a Cadillac crossed with a limousine. Luxury almost to the point of being boring. A race bike it is not...even if the trail numbers alone would lead someone to think so.

What it is, is a bike for crossing continents while the brain is free to do anything other than ride the bike.

Road Fan

What happened to convince you a 55" wheelbase is too short? Did you panic brake it until made you do an endo?

On bicycles riders are advised to shift their weight back over the back wheel when braking very hard.