Poor stability on New Bike.

[Colin S]

Hello all.

I have just changed bike and find it very unstable especially in even minor cross winds / gusts especially at speed / downhill.
My new bike is an aero road bike with 45 mm rims. I would not have expected these to cause any problems and certainly not the level of nervousness I am getting.

Any ideas of other things that might cause a problem like this. I have checked for any looseness in the wheels and headset and all is fine.

TIA

Colin

 

[fossyant]

Thats your problem. Aero road bike with deep rims. Don't do sidewinds well.

 

[DogmaStu]

My Trek Madone SLR on 60mm wheels really feels 30mph gusts and can be unstable at speed but my Wilier non-aero on 45mm wheels doesn't really, it's fine. Obviously strong winds will blow the bike a bit regardless but is manageable up to those wind speeds in my experience.

It really depends upon how aero your bike is. Aero bikes will act as a sail with lateral winds and this can be a good thing but you need to learn to adapt to how they handle in those conditions.

My Pinarello on 50mm or 60mm is fine up to about 30mph crosswinds.

But yes, an aero bike with deep wheels will behave very differently due to the sail effect.

 

[I like Skol]

Might not only be the aero frame and deep rims making the difference, have you compared the geometry of the previous bike to the new one? I suspect you might find some significant differences, namely a steeper head angle and maybe less offset/rake on the fork. Different bikes handle differently and the designers can play around with the geometry to enhance some characteristics that they see as desirable, but at the cost of other factors. One man's sharp, precise cornering can be another's twitchy handling..... Sometimes it is simply a case of changing your mindset/technique and adapting to the new behaviour.

 

[TissoT]

45mm rims shouldn't cause any problems in a cross wind.

If the frame is carbon and the bike is light in weight overall I would suspect that will cause you to be twitchy.
23mm Tyres take a bit of getting used to if you haven't ridden them before.

Its probably something you need to get used to
Let someone you know ride the bike to see what they think in regards to stability/handling

 

[DCLane]

Similarly my NeilPryde Nazaré can be "interesting" in cross-winds as I've got 55mm carbon wheels. On windy days I ride something different.

 

[13 rider]

If you've not ridden deeper sections wheels before yes they seem twitchy when first riding them . You will get used to them and adapt to riding in crosswinds . I do occasionally take out bike number 2 with less deep sections wheel if the wind is forecast to be strong and gusty because it the gusts that catch you . Look out for gaps in hedges etc which can catch a sudden gust

 

[Alex321]

Hello all.

I have just changed bike and find it very unstable especially in even minor cross winds / gusts especially at speed / downhill.
My new bike is an aero road bike with 45 mm rims. I would not have expected these to cause any problems and certainly not the level of nervousness I am getting.

Any ideas of other things that might cause a problem like this. I have checked for any looseness in the wheels and headset and all is fine.

TIA

Colin

You WILL notice cross winds with 45mm rims, unless the bike is very heavy. Aero also doesn't help. Both deepish rims and aero are designed to be efficient in still air or a headwind, when they are just cutting g through the air in the direction of motion.

 

[Alex321]

45mm rims shouldn't cause any problems in a cross wind.

If you are a very good rider, or you and/or the bike are pretty heavy, maybe not.

Otherwise, cross winds WILL cause issues with that depth of rim. Mine are similar, and I very much notice gusts or gaps in the hedge when there are significant cross winds.

 

[Cycleops]

Aero bike with deep rims and race geometry. Well wha'dya know.

 

[Sharky]

I treated myself to a front tri-spoke wheel for club 10 mile timetrials. But found it a real battle when cross winds. Now I only bring it out on calm evenings.

 

[Jameshow]

Aero bike with deep rims and race geometry. Well wha'dya know.

No sweat Einstein!!!

 

[Peter Salt]

More info is needed to provide you with any sort of useful advice. There are different profiles of same depth wheels, and they'll handle side winds differently. What wheels do you have? The bike will also be more or less responsive (or 'nervous') dependant on headtube angle, trail, rake, stem length, handlebar width and a few other bits. What was the old bike and what's the new?

 

[Colin S]

Thanks for all the replies
Wheels are ZED 45s and geometry is the same as my other bike.

Looks like I got what I should have expected but didn't.

Will just have to suck it up and get used to it I guess.

Colin

 

[I like Skol]

What was the old bike and what is the new bike?