Help! I've gone through 3 tubes now on my daughter's Specialized Hot Rock bike. This pic is the front tire, which is still holding air (for now), but the back tire has killed 3 tubes now. I thought the hole in the rim was too sharp, so I filed and sanded it smooth, but it just cut into the valve stem again last night after only a few blocks of riding.
I've never had this happen on any of my bikes, ever. Got this bike second hand, but I'm assuming the rims and tires are stock.
I've replaced bike tubes and tires before, but that was on a little 12" kids bike. This is a 24". Am I supposed to put some sort of adhesive on the bead for larger diameter tires like this?
I'm kind of at my wit's end, and it sucks because it's making my 10 year old daughter afraid to ride her bike.
by ScotWithOne_t
16 Comments
This only happens when tires are under-inflated. Make sure you add air regularly and this will end.
10 year old putting down some mad watts! 😉
What pressures are you running? As if too low this can happen
Tyre is slipping on the rim. This mainly when the tyre is under the minimum safe pressure stated on the sidewall, either that or your daughter is built like the Hulk and is putting loads of energy through the tyres.
This happens when the tires are a loose fit on the rim. You can try adding extra wraps of rim tape to make it a tighter fit.
More air pressure, use talcum inside the tire. Maybe the tire is old and the rubber has hardend, and slips too easy on the rim.
Under inflated!!!
Tire shifts when tire pressure is too low. Keep the pressure at the recommended pressure. Pump them up once a week.
This happens because the tire is under inflated.
If there’s not enough pressure, the tire can slip around the rim and drag the tube with it.
Because it’s a larger volume tire, make sure you are inflating to the recommended PSI. Don’t go on feel alone.
[better tubes with threaded valve shafts](https://www.bike24.com/p25274.html)
I’d guess the pressure will drop more quickly because there is a smaller volume of air in the tyre to start with. Once it gets lower the tyre will start to migrate around the rim as it rolls with weight on it. The tube will shift with the tyre, valve gets pulled off perpendicular. Check the tyre pressure more regularly and don’t let it get low. talc can help a little if the tyre does migrate. The problem is more pronounced with small tight radius tyres.
Maybe adhesive rim tape will help.
Re tape the rim it will help reduce it from shifting
She’s riding the bike when the tires are low. This would be a good time to show her how to use a floor pump and how to read tire pressure. She should not be riding the bike when her tires are under inflated. I’d start at 35psi.
Tires are under inflated.
S Never too early to start them on tubeless /S
Is there oil/grease on the rim/bead? Clean it with isopropyl.
Check the ETRO table if the rim/tyre combination is within specification.