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Hi,
I'm trying to repair some 454 Air U-Turn Pike forks and found that the threads appear to be damaged on the air shaft foot/end. Not sure how but when I inflate they leak air from there. Is this likely? Can they be converted to coil or should I scrap them? Or does any kind soul have an old Turn Air setup that I can purchase?
Thanks
Chris
Are the threads mangled internally or externally? I had something similar and solved it by replacing the valve core in that bottom valve from an old wheelbarrow inner tube. Might be worth a try - I think they’re still good old forks. Hope this helps!
Are you saying when you inflate the positive side it comes out the negative valve? Aren’t they two separate springs? You can run with 0 psi in the negative side it just wouldn’t be very supple on small bumps?
Threads were chopped up on the outside so in my infinite wisdom I filed them off.
Changed the valve core first up and didn’t help.
When I inflate the negative chamber I can hear air coming straight back out around the valve/thread area.
I can get a new lower air assembly from US, but keen to see whether I can sort it diy.
Thanks
It sounds like you have a seal leak on the negative spring. either the shaft or the stanchion seal would allow air to pass by. however, I've never taken an Air U turn cart apart so not sure how far you can strip it, or if it takes a standard RS seal kit.
PTFE Tape on the mangled threads?
Probably a completely useless offer but I have a spare Revelation 426 (140)) air spring that holds air that you can have for nowt if the parts are of any use.
Thanks all. Might go and tinker with some PTFE tape. However, @VMGSCOT - think I may take you up on your offer!
Are you talking about the threads that the pump attaches to? If so does the air stop escaping as soon as you stop pumping?
Have you removed the fork lowers to check the air spring yet?
The air pressure should all be inside the stanchion, the lowers should just have bath oil in them.
If the lower seal head inner or outer seal have failed they could leak air into the lowers.
2010 Pike 454 service manual
Coil conversion would be easy, and good. (the 454 is pretty much just an air 426).
I could be wrong but I think the air cartridge from the Revelation Team that followed these Pikes fits, and uses a fully enclosed air spring rather than using the stanchion as the air spring outer. But I might be misremembering.
Thanks all. From my reading I’m hopeful that Vincent’s Rev air spring should fit 🤞🏻
Here's what I have @cjr61 ... its a complete air spring side 'cartridge' out a Revelation 426 U-Turn Air (2009?). Still holds air and has all the bits for the adjuster knob, valve caps, footnut.
Can you convert it to a coil if necessary? Can’t remember if those old Pikes could or not
I've recently got my old bike out with an identical fork, never serviced since new in 2009 but lightly used. Not as plush as I recall so any recommendations for servicing? Anyone used badass bikes in the Mendip?
Just seen that mine is actually a 426 uturn air. Does that change anything in terms of serviceability?
Difference is just the crown and steerer, 454 being lighter
I think I might have a load of U-Turn coil assemblies kicking about if they'd be any use? No charge, you can have 'em all and see if you can make them work. I have no idea what springs are in them though, soz.
I'd certainly give that a go if conversion from air to coil is viable. I'll PM you.
@csb - I had the Air U-turn assembly left over (that I sent to @cjr61) from converting Revelation 426 to coil. It was a straight forward swap. I also converted a Fox Talas to coil using the same Rockshox parts - there must have been a moment in time when the top cap threads matched between the manufacturers!
Thanks that's reassuring!
They're super easy to work on. The air spring @vmgscot sent over has done the job perfectly!
Top STW support as always