Pirelli Cinturato tires leaking air through tire walls. What should I do? I built this bike up last year and I always have to air the tires up before weekend rides. I always suspected a small leak in the valve stems or something, I just never got in the way of riding so I never addressed it.
by krau58
10 Comments
The tires are labeled as tubeless ready, but clearly they’re leaking air in the sidewall. This is why I find sealant on the tires sometimes. I always thought it was from burping the tires on this one harsh bump I have to ride over or the valve stem leaking air and the tire’s sidewall hook loosening on the wheels overnight. They seem to lose a few psi over the course of a short ride too, which isn’t terrible, but it is annoying.
What should I do? Should I contact Pirelli? Accept it and get different tires? Thoughts? Thanks!
How do you know it isn’t leaking through the sidewalls and the valve stem?
This is pretty normal for a lot of tires- especially more supple skin wall tires. I’ve mostly had this issue with WTB tires, but my Maxxis tires will have sealant bead up on the walls once they’re worn in.
Honestly, you should be checking/adding air before each weekend ride. I check my pressure before every ride, and I commute daily and do pleasure rides on the weekends.
Definitely contact customer support. You might get replacement tires and the problem *might* go away, or it might not.
Top off the sealant through the valve stem. Inflate the tire. Take the wheel off. Hold the wheel horizontal to the ground and shake it around to splash sealant against the sidewall. Fan it up and down, then rotate the wheel and fan it again. Flip the wheel and repeat. Do both wheels.
I did this with a new WTB tire last week; worked like a charm.
I’ve seen/heard this problem from many brands, including all the ones in the comments. Some things you can do to mitigate the likelihood of this happening:
1. When initially setting the tire bead, do not exceed the rated max pressure of the tire.
2. Do not run the tire flat, or at extremely low pressures for extended periods of time.
This will happen to any of the supple carcass tires, regardless of branding. I don’t understand the WTB hate coming off this sub, but it’s not just them. I’ve also seen this problem on RH, Pirellis, and a few others. I think it has to do with how thin the sidewalls are, and as the fabric flexes, it creates microrips in the rubber casing. This is where the sealant is seeping out. Other than the inconvenience of having to pump up the tire more often, this doesn’t really affect their performance. If it really bothers you, try contacting Pirelli, but YMMV.
I ride these and have never had a problem with sealant. Use Stans Race.
I have the same tires and this exact issue was causing me to go mad for weeks… I wound up finding 3 distinct leaks on the sidewall with some soap and hit them each with a drop of gorilla glue… now my tires don’t go flat between weekend rides
I had these tires. They were garbage. Never flatted so many times in my life.
Have you considered your sealant has gone off/bad quality? Get a new fresh bottle of better quality sealant, remove and clean old sealant and replace with new one.
Don’t forget to shake the bottle throughly first.
Use silca or another race ready sealant.
If using more sealant isn’t a solution, I’d contact the vendor before contacting Pirelli. I had what I considered a warrantable condition and Pirelli asked that I contact the shop where I got the tires from. It’s possible that you may be asked to submit your tires so that Pirelli can inspect them, which wasn’t asked of me fortunately. Thankfully my shop sent me a new set of tires.