Just bought a new pair of 2009 U-turn Revelation forks from Bike Outlet, set them up with recommended air pressures and on first XC ride out today they were producing some worrying knocking sounds on the climbs - seems to be only at the full extent of the stroke when pulling up on the fork. Not sure but it might only be from the left side (the U-turn side) - also the knocking is most pronounced when the fork is wound down off the 140mm and when at 140mm the knocking is barely noticeable. It feels loose and just like when the bushes were gubbed in my old fork. Anyone had any similar issues wth a new Rev fork??? - is it something I can sort (i.e air pressures) , is it somethign that will "bed in" or should I contact the seller immediately and get them to take them back as faulty???
Normal IMO. From tft...
[i]My U-Turn air fork knocks slightly, what is this?
There’s play in the travel adjust helix. A small amount of play is necessary because if it was tight you wouldn’t be able to turn it, however this can cause a knock. During service, we reduce this as much as possible but it can never be completely eliminated. [/i]
http://www.tftunedshox.com/faq/rock_pike_reba_revelation.aspx#link10
My 2 sets of U-Turn Rev do it.
Yes, me and somebody else I ride with had same thing.
Mine was very bad, was sent back to Fisher and I think they just filled it with oil properly.
Is there a solution? I thought I read that the method to reduce it was to apply a good amount of grease to the helix but I could be wrong 😕
In my case I think the fork hadn't had enough oil put in at the factory, so it must have been easy to fix.
mine started doing this today, im really pleased that this is normal on my really expensive brand new forks....
My old 08 Rev does this, my new-ish 09s don't but I won't be surprised if they start. It's not a problem though, it's just a noise, not a symptom of a fault or anything
I would contact Sram to enquire about warranty, I read a few months ago (in MBR I think) that there was a problem with production of some forks that produced a knocking noise from the U-Turn side of the fork. I went for the all travel version as I had problems with the U-Turn on other forks. Don't go with the recommended pressures they are way out.
is this not the same problem as the old fox vanillas used too have
on them there was a heat shrink tube hlf way down to stop this
and occasionally it would slip down and cause a clunk that sounded like you forks were going to collapse
Cheers for the comments folks
I got a reply from Fisher about the knocking - here it is:
"The problem you are experiencing is of a tolerance between the U-Turn assembly and the top cap of your forks. The problem has been cured by releasing all the air and then setting them up again for your riding weight. However, if this does not work we can cure the problem here by reinforcing the shim in the top cap to eliminate the knocking."
So will give it a shot and see - if not then back they go. Its a disconcerting noise to be accepting from a brand new fork - my other sets of U-turn Pikes never did this.
mine have done it since day one its annoying but doesnt affect performance. Although this does make me rethink when buying my next fork
Mine feels a bit odd (like there's play) when pulling up hard but doesn't make an audible noise that I've noticed.