While cleaning my time trial bike I've noticed many scratches in the frame. See pictures below.

Scratches on a time trial bike

Scratches on a time trial bike

Time trial frame

My tire pressure is usually around 100 psi, depending on the weather conditions or circuit. My wheels are the following: https://9thwave-cycling.com/product/road-sl50-wheels/

Should I be concerned? What can I do? Thanks in advance.

  • 1
    Did you ride the bike in the rain? With tight tolerances the extra width added by the water can act like sandpaper if the water is also picking up fine sand or dirt.
    – Rider_X
    Oct 1 '18 at 20:19
  • Unfortunately, yes. Did a commute to work (approx 50km) with it and got some rain that day.
    – antao
    Oct 1 '18 at 20:27
  • Is it the original wheel and tyre ? I'd be asking Cervelo why this happened, and whether its covered by warranty. If you changed wheel or tyre at anytime in the past, then that's a different matter. Nice bike.
    – Criggie
    Oct 1 '18 at 22:55
  • The epoxy I've looked at/worked with was rated for 120°C maximum and a rubbing tire could easily exceed that. Only the manufacturer of the bike will know the exact rating of the formula they used.
    – Nobody
    Oct 5 '18 at 10:37

Looks like you have had significant tire rub on the frame for a while. I'm surprised you did not notice the friction and drag.

If the abrasion is not all the way through the paint (the worst seems to be into the light colored primer) then you are probably OK in terms of physical damage. I might still be concerned about the possibility of heat damage, but if there does not seem to be heat damage to the paint the CFC epoxy is probably OK.

Presumably the bike did not always suffer from tire rub. Did you change to a wider tire? Have the dropouts been damaged? Looking at this image of a P2 on Cervelo's website I'd say there is something significantly amiss that has let the wheel shift forward. [Edit: better picture provided by OP shows that the wheel has not shifted.]

  • Thank you for the answer. I have not changed the tires and the dropouts are fine.
    – antao
    Oct 1 '18 at 20:03
  • 2
    @antao Something is wrong, check the image I linked to in updated answer. In that pic the curved seat-tube follows the circumference of the tire. Your wheel has evidently shifted forward somehow. Oct 1 '18 at 20:06
  • I've added a better picture. It's night time in Europe right now and the light conditions in that room are not the best.
    – antao
    Oct 1 '18 at 20:29
  • 2
    @antao much better, I think the rain/dirt issue Rider_X put forward in a comment is likely to blame. That's actually good as presence of water would stop heat build up. Physical damages can be seen but heat damage may be invisible. Oct 1 '18 at 20:37
  • 1
    Dynamic circumference expansion of the tyre due to speed, I'd say. And there are noticeable size differences for tyres of the 'same' size.
    – Carel
    Oct 2 '18 at 7:47

That's definitely tire rub. That frame has horizontal drop-outs to allow you to adjust the forward-back position of the wheel. When you take the wheel out, look in the dropout and you should see screws in there. I found a photo on the slowtwitch forum. Back them out a bit and then do another test fit. Make sure that the skewer is properly tightened too so that the wheel doesn't slip forward under load.

As far as the existing damage, I would recommend getting a reputable local bike shop to take a look at it because it's very hard to tell just from the photos, but it LOOKS like the damage is just to the paint and possibly the superficial outer layer of carbon. Again, get an LBS to inspect it to be safe. If it's just cosmetic as I suspect, you can seal it with a clear coat of some kind. Clear nail polish works surprisingly well.

  • 2
    FWIW, I don't see any actual fibers exposed, and the rubbing might not even be through the primer under the paint. From what I see, I'd be comfortable clear-coating the rubbed area and riding it. Oct 2 '18 at 15:40

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.