Valve Issue - likely cause?
Discussion
I am having issues with both my tubeless wheels. Been fine for some time but after a puncture and tyre split a few months ago I was forced into the local bike shop to resolve. I had issues with both wheels since but the front one in particular is causing me grief.
It won't accept air properly - when attaching a track pump you may get one or two small bursts of air into it before the connection seems to break and loads of air then "pssssss's" out when you pump. I know this happens from time to time, but this is constant. I have had to develop a strategy of fiddling with the height of unscrew and trying to be very careful, but I can't get enough air into it - only seems to get to what feels like 45/50 PSI. Air comes out of the valve when you push it so I can't see it being a blockage.
I have now started using my Truflo electric pump on it as at first this seemed more successful, but, I am getting the same. I attach it and the pump only operates for around 2 seconds, it goes from a reading of 35 or thereabouts up to 150 straight away and shuts off, the air just isn't going in. I end up having to keep using it over and over again doing 1 or 2 second bursts. The tyre does seem to get some air but it is extremely slow, and still, I can't get any more than what feels like 45 to 50 PSI in. I can feel the rim hitting the road when going over small cracks or small increases in height. Yet apparently people want to run tubeless tyres at low PSI - personally I hate the feeling and want at least 80 in there.
Its a Giant Propel and so quite a twitchy / agile bike - when cornering I can just feel there is not enough air in the front. What causes this issue? Both valves tyres and sealant was all replaced a few months ago by the shop.
It won't accept air properly - when attaching a track pump you may get one or two small bursts of air into it before the connection seems to break and loads of air then "pssssss's" out when you pump. I know this happens from time to time, but this is constant. I have had to develop a strategy of fiddling with the height of unscrew and trying to be very careful, but I can't get enough air into it - only seems to get to what feels like 45/50 PSI. Air comes out of the valve when you push it so I can't see it being a blockage.
I have now started using my Truflo electric pump on it as at first this seemed more successful, but, I am getting the same. I attach it and the pump only operates for around 2 seconds, it goes from a reading of 35 or thereabouts up to 150 straight away and shuts off, the air just isn't going in. I end up having to keep using it over and over again doing 1 or 2 second bursts. The tyre does seem to get some air but it is extremely slow, and still, I can't get any more than what feels like 45 to 50 PSI in. I can feel the rim hitting the road when going over small cracks or small increases in height. Yet apparently people want to run tubeless tyres at low PSI - personally I hate the feeling and want at least 80 in there.
Its a Giant Propel and so quite a twitchy / agile bike - when cornering I can just feel there is not enough air in the front. What causes this issue? Both valves tyres and sealant was all replaced a few months ago by the shop.
I had this with early Peatys valves. Definitely sounds like sealant gumming it up so that air is escaping "backwards" into the pump. New basic valves are cheap but bike dependent, the newer type of high flow vales like the Reverse ones mentioned are great. Less chance of them getting gummed up and can seat tyres on rims far easier - I'm running the new Peatys ones on two bikes.
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