Bike is a carbon frame tarmac SL4 that is mostly ridden outside and occasionally on trainer.
Yesterday I noticed a small crack in the paint in the rear aluminum inserts. When pulling, a big chunk came off, this happened on both sides.
Did I damage my frame by using the bike on the trainer? Does it subject the frame to a normal mechanical stress to this point?
I never ride standing on the pedals while on the trainer, I am always on the seat.
Any clues on what caused this?.
Edit: I live in a country where we don’t have seasons so no we never salt the roads. I live in the mountains far away from the sea, so all corrosion must have come from sweat
Thanks,
by KiteCat777
9 Comments
I wouldn’t ride that carbon on the road anymore.
Not quite sure but it looks like oxidized aluminium. Meaning is just cracked paint. If this parts is now inside and will remain inside i would not worry about it. Aluminium does not keep on oxidizing like steel does. You can wire brush it and apply some new paint for the looks.
It’s corrosion from either sweat or road salt not from the trainer.
I do believe the core series trainers can be very hard on a bicycle frame. I don’t put my carbon bike on there, and even worry about my aluminum. I intend to switch to the Rollr this year as it appears to put much less stress on the frame.
Do you ride in an area where the roads are salted ? Looks like the aluminum is starting to pit.
The salt in your sweat has got in there and corroded this out, its possible those are bonded aluminium parts. 10 out of ten for effort, literally!
The trainer is hard on the frame, When you stand on the pedal;s the frame wil flex on these points because the trainer is not moving in the vertical plane.
Yeah that looks exactly like corroded aluminum.
Corroded by sweat or salt from the road.
I’d strip the paint from all aluminum sections of the frame and brush it with a soft wire brush (brass). Then take a close look if the corrosion goes deeper into the carbon/aluminum joints. If it’s ok, you could clear coat that parts again, or apply some grease or wax cover, where the sweat won’t get through.