I discovered a had a huge hop in my Zipp disc a few days ago (just before I left for Lonestar) when I stuck it on the trainer. I had mounted that tire several weeks prior for a race I never did so I hadn’t ridden on it yet. Not ideal since it was the day before the race, but I took it off and put it back on without regluing to see if it might have been a poor glue job by me originally. Still had a big hop after inflating so I tried another, brand new tire - same thing. Stuck the wheel in a truing stand and it’s definitely out of round. I don’t think they’re trueable(or is it truable?), so I’m assuming I’m SOL at this point? Does a disc wheel that has a bad hop negate the aerdynamic benefit?
How are you determing that it is out of round? I’ve got an old Zipp disk and never checked it but I would think it would be easier to make a disk round than a spoked wheel.
Styrrell
How are you determing that it is out of round? I’ve got an old Zipp disk and never checked it but I would think it would be easier to make a disk round than a spoked wheel.
Styrrell
Truing stand.
Out of round like a flat spot on a circle, or out of true from side to side?
Either way I don’t theink that it will affect it’s aeroness, just its rideability.
“Either way I don’t theink that it will affect it’s aeroness, just its rideability.”
If it’s not rideable, does the “aeroness” matter?
A flat spot. You should hear the thing on the trainer…bump…bump…bump…it sounds really bad.
Can you tell if its the disk itself or is the disk fine and a tire problem? If its the tire then its either mounting or a bad tire. One possibility is that it could be a build up of old glue. Gentle scraping might be a quick cheap fix.
Styrrell
is the wheel out of round on the truing stand with no tire? i’ve had different carbon wheels in the past where the hole for the valve stem wasn’t large enough on the rim and the stem didn’t insert properly, giving the tire a high spot that would do this ‘bump…bump…bump’. grinding a little material away at the hole for the valve stem (like you would to countersink a flat heat screw) solved the problem. just something to check…
My bet is that the hop is at the valve stem. If you are on Vitoria I really really bet that is the case. Only real fix if you are on a Corsa CX is a new tire. I had one that was so bad I sent it back. The hope I beleive is the extra thick area of tape, and the over lap that is just past the valve stem. No matter what tire…I am willing to bet that it is at the valve stem - reinstall is the first order of business.