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I have a 2007 Tarmac Expert Double with a Mavic Kysrium Equipe rim spoked to a Mavic Kysrium Equipe, 24 hole, Mavic QR rear hub.

I recently upgraded to 28mm tires from 25mm and I had the rear wheel recently trued so rolls smoothly and clears all the stays.

However, when I climb (out of seat) or make sharp turns, the tire rubs on the sides of the seat stay.

When I press on my rear wheel to the left or right, it gives enough to rub against the brake pad as well as the sides of the seat stay. If I loosen the brakes the tire rubs a bit more on the right side than the left.

Gooling around shows that my hub might be going bad given that I have put about 5-7k miles on the bike.

Is this repairable? Does it make sense to buy a new wheel? Can I just replace the hub with a PowerTap and new spokes? How dangerous is it to ride with so much play with the wheel.

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    First thing to do is to lift the rear wheel off the ground on some sort of a stand (or flip it upside down or hang from a rope) and, with one hand on the frame and the other on the wheel, "wiggle" the wheel. If you can feel any "play" (a sort of rattling effect) in the bearings then they need to be adjusted. (It's vaguely possible that the bearings are going bad, but not terribly likely -- even a so-so hub should be good for 20K miles or so between servicing, and should be good for 100K or more if properly serviced.)
    – Daniel R Hicks
    Mar 13, 2017 at 22:12
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    In 2007 the norm was 23mm and 28mm tyres were deemed uncool for racebikes. Your bike was built with narrow tyres in mind.
    – Carel
    Mar 14, 2017 at 8:17

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Unfortunately 28mm nominal tire width can be too larger for many modern road bikes. Note that actual measured with depends on many factors including: internal rim width, tire construction, tire profile, tire age and wear, inflation pressure. As such, one combination of tires and wheels can work while another may fail if you have tight clearances.

It is also impossible to build a bicycle and wheel set without flex. As such, there needs to be a minimum safe tire clearance. Just because the wheel spins freely in the stand does not mean there will be appropriate clearance for actually riding the bike, especially for heavier/stronger riders. I would suggest assessing how much clearance is available with 25 mm tires (perhaps(typical max clearance on many road bikes). If the clearance is already tight (e.g., less than 1 cm) then going up to 28 could be a stretch.

The more recent version of the tarmac (e.g., disc version) can clear 28 mm, but I doubt older rim brake versions can. It is best to ask the Specialized Help Desk to get an official answer.

Question of Hub Play

All wheels, will have some side-to-side flex so it is unclear whether or not there is a problem with the hub. Typically, if the bearings have developed play the wheel moves side-to-side with a very light touch, if more force is required it is likely wheel flex. 5-7000 miles is not a lot of mileage, but this also depends on the conditions they were ridden under.

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The actual reason for rub is that wheels are not infinitely stiff, but flex a bit laterally when climbing out of saddle or cornering. This is normal and not dangerous but becomes more apparent when you have tires that only barely clear the frame when the wheel is entirely straight.

The sad truth is that many road bikes don't have room for 28mm tires, and yours seems to be one of them.

If your hub had play in the bearings, you could feel it by just wiggling the wheels sideways with your hands, no need to push with significant force.

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I have a cheap 20" folding bike that would give wheel rub after a while. I found out that the serrated nut surface under the QR was polished smooth. So under load from the chain, the axle pulled forward.

My fix was to use a triangular rats-tail file and recut deeper grooves into the QR's serrated surface, leaving a more grippy surface to bite into the dropouts. This took over an hour of filing due to the hardened steel of the QR.

This will only help if its your wheel axle moving relative to the frame. If its flex then this won't help.

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    Axle sliding in dropouts is by the way the reason why practically all derailleur bikes manufactured since 80s have vertical dropouts.
    – ojs
    Mar 14, 2017 at 20:27
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28mm are too big for the bike. It's as simple as that. You will always get some flex in the wheels and frame as you pedal More power and lean angles and rider weight = more flex. Just because the tyre clears the frame by a 1 or 2 mm doesn't mean it will clear under load. I suggest you go back to 25mm tyres and save up for a bike that is designed for 28mm if you really want to run them.

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