Can anyone advise please?

I raced twice this weekend and both races required a change of bikes on lap one after what appears to be leaking valve extenders led to soft/flat tubs whilst hanging around at the start etc.

I run FMB tubs and with deep dish rims so need an extender. After pumping up or changing tire pressure, it appears that the valves are leaking slightly, presumably as the nipple is slightly depressed inside the extender?

What type of extenders do people use and is there a way round the self opening of the valve like this?

Thanks

Get the tufo extenders that basically extends the valve that the core screws into they come in 3 different lengths, also make sure you use some Teflon tape to seal the threads while installing them. Good luck and you should be able to buy these from the shop that sold you the FMB's.

Thanks for that - I have used the tufo extenders with tufo tubs before. Unfortunately, the valves on the FMBs don't have removable cores to screw the extenders in so this doesn't work.

I ran into the same problem (challenge) with FMBs. Great tires, but Francois needs to put in stems with removable cores. I suspect he will be doing this as it is the only complaint of his tires. The SPs are one tough tire!

With a removable core, the tufo or Vittoria extenders are the best. I found two options. Topeak makes an extender with a core built in. Realitively cheap, but hey need a modification to work. There is a rubber insert on the end of the extender that screws into the tube. This will pop out after the first use. Use super glue (sparingly so as not to glue the valve tight) on the rubber insert to attach it to the extender. The more expensive option, and the one I've evolved to is the problem solvers extenders with the valve built in. Better made than the Topeak, but expensive. About 15 bucks each. Remember to add a bit of teflon tape on the stem threads for good measure against leaks at this interface.

Good luck

Frank