Evening all,
I have a set of U-Turn Air pikes which were serviced about 5 months ago and I have noticed that the negative seems to be losing a lot air (25-30 psi) when I check it before a ride usually every weekend or more. Tonight I ran some experiments using two different shock pumps and got the following. On the negative air I pumped it upto 100 psi detached the pump and then replaced it. The reading was then around 70-75 for both pumps. I then did the same on the positve air and the rear shock to rule out knackered pumps and only lost about 5 psi on both.
Is the negative air suppose to lose that much?
Yep, coz it's a smaller chamber than the +ve.
Make note of how much it looses on reconnection and then you can tell if it's actually loosing some over time.
Also, always empty the -ve, pump the +ve and then refill the -ve, or you'll get funny things happening.
dodgy valve core is to blame imo
is that a bit like happy hard-core?
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igmc
I agree with geewavetree, just had to replace valve core on my forks for same reason.
what bike wisperer said, its not loosing air, it just takes some to fill up the shock pump's hose and dial so the pressure will always drop when you connect the hose.
dodgy valve core is to blame imo
no, it's as bikewhisperer says. Same on every pair of dual air RS forks i've ever topped up
Prob right but for a valve you can remove from innertube for free its worth trying? this was the prob in my fork but i couldn't get any air in.
completely normal to loose that much air
The negative chamber is very small... When you connect a pump to the valve you lose quite a bit of pressure from it as bikewhisperer says.
My Pikes are four years old and have always been this way.
