2014 Reba 29ers supposed to be 120mm travel but only getting just over 105 ish mm so ordered a longer airspring. Took forks apart only to that the same airspring is already fitted! So it looks like that they'll be staying at 105mm...
The forks had recently been serviced I'd say as they were clean and well greased and worked perfectly before I touched them 🙁
I cleaned and relubed the foam rings and they were a pig to refit with the seals still in place. Regreased airspring, oil in the lowers and put back together.
So tried inflating them and it's taking a long time to inflate and they're not getting to full travel, stiff in movement and sound a bit sqwelchy. So all in all I've done a good job!!
Any pointers please for those symtoms while it's still in the workstand?
Cheers
You sound lost.
Take them to a shop.
How much stanchion is exposed when the fork is fully extended? Is it the full 120mm? IE, are you getting the top 105 km of travel or is the fork stuck down ?
If they are stuck down, ie not showing all the stanchion, let the air out of the main schrader valve, then take the airside footnut off, and stick a small allen key up there to release another hidden schrader valve.
You should get a hiss and your travel back, but this problem is caused by the fork failing to equalise pressure between the positive and negative chambers, and may return at some point. The classic reason is grease blocking the transfer port at the top of the air shaft, but it's possible that you need to replace some seals there.
https://singletrackworld.com/forum/topic/rock-shox-reba-solo-air-problem/
PS remove the wheel before doing this, it can spray a bit of oil out.
Scienceofficer - Thanks, very helpful.
Davesport - I can't remember the total amount of stanchion showing, just know I measured around 105mm Travel. The forks were working somoothly just short on travel so I assumed it had a shorter airshaft fitted so ordered the 120mm one and as I said they looked to have been well looked after.
It's my first time working on forks so it's something I have done I'm sure.
martinhutch - Thanks, didn't realise there was another valve there I'll have a try with that and check the link out cheers.
Only had time to have a quick look at these today.
Removed the LH footnut and released the pressure from the valve, replaced and put around 60psi in and pumped the fork a few times and there was around 105mm of stanchion showing.
Pumped to around 100psi, around 115mm stanchion showing, forks seemed to be moving ok.
Removed the pump and the psi dropped to 50-60 and now not increasing when pumping....
Think I'm going to take the lowers off again and check things over.
Just need to know where the transfer port is so I can check for grease, any pointers please?
Ta
It's at the top of the airshaft, looks like a small dimple.
But before you start delving into that, let the air out, release the bottom valve again, then pump them up in 15psi increments, pushing down and pulling up the fork a few times between each to see if you can force it to equalise between the chambers. It is meant to equalise on top-out rather than when compressed.
I have a set of similar vintage that had the same problem and the source of it was a scratch in the shaft of the airspring. It was allowing air past something or other (I forget exactly what!).
Put your clean new one in even if it looks the same when you take them apart. That may do it.
Let all the air out and compress them completely if you still bottom out at 105mm there's too much oil in the damper side.
Cheers guys, will have a look in a couple of days.
So removed the airspring, where am I looking for the air transfer port?
Thanks
My understanding is that it's a small indentation inside the stanchion. Not on the airshaft.
Lol. I got the wrong end of the stick then 🙂
Bit of an update....
So, fitted new airshaft taking care of not over greasing near the transfer port, new seals & foam rings, 5ml oil in each leg, tighten footnuts to 7nm
End result = no change, pump and it only goes to 60ish psi after a lot of pumps ie, a lot more pumps than it normally would be.
Wondered if air mught be leaking out of top air cap so swapped ut for another I had and no difference.
I'm now wondering if this might be something to do with the damper shaft? When I refitted the air shaft first time round I did push both the air shaft and damper shaft in a few times before fitting the lowers. Am I clutching at straws here....
Like I said at the start the forks worked perfectly before I touched them....
Take the lowers off again and make a decision about which side is causing the lack of travel issue.