Fishtailing Rear Wheels

sonny73

I got some 30mm aero rims a couple of weeks ago, never had rims aero or that deep nowt too fancy but great for me and very happy with the weight and ride etc.
LBS put them on all good, stunned however at times how much I notice the back end being slightly pushed/sliding out, even with what must have been the tiniest breeze as I couldn't feel any wind elsewhere.
Is it something to get used to or could I have something up with the rear wheel?
It was kind of funny if a little disconcerting at times and reminded me of when I started riding years back and first getting wheel wobble

sungod

depending on the wind angle/speed there can be quite a bit of force on deep rims

if you can say whch make+model, you've got a better chance that someone could give advice based on their own experience

Wamas

I would guess that your bike set up means that you have much more weight on the front wheel than the rear.
What is drop between the seat and your bars, and what length of stem are you using?

All being equal, if the balance of your bike is correct, both wheels should feel the force of the wind, not just the rear.

I have 30mm rims, and only when there is a strong cross wind do I find that there is an issue.

I have noticed recently after the longish dry spell, that when there has been a little rain, the roads have been slippery in the morning (diesel residue), this may have had an effect also.

sonny73

Cheers for the feedback chaps, they are Pro-Lite Treviso's.
Stem is exactly 115mm from head set centre to bar centre. The drop between my seat and bars is 83mm. Its all been set up to my exact measurements by the LBS, been riding it years and always been perfect.
Having ridden on them again I think it may be a combo of as you say greasy roads and light winds; it is a feint sensation after all I guess.

redddraggon

Cross winds just affect the front loads more than the back. 30mm rims are hardly deep and TBH I doubt they are to blame for "Fishtailing rear wheels" anyway.

ride_whenever

I'd say either the frame being out of alignment or the rear dishing not being quite right would be far more likely than crosswinds tbh.