Rail (625Wh) Shock knock

[Drumhitter]

Hey everyone!

I'm getting a knocking from my rear shock on the downs. bolts and mounts all correct and torqued up properly (RS Deluxe coil). I can feel a tiny bit of movement of the bolts, not at the actual shock mount.

Has anyone else had this? Thinking about trying some thin washers between bolt and frame.

Thanks in advance

Ant

 

[Stihldog]

Besides the bearing mounts and bearings, there could be a few other things to check.

Shock bushing mounts. Correct plastic spacers, which include 2 plastic washers and 2 plastic spacers for each mounting point. There should be no lateral movement when these are installed correctly-fairly tight fit.

Is the air can air valve inserted to far? It is possible to turn the air valve too much where it can interfere with the shock operation.

If the shock hasn’t been serviced for a while it could be something internal…but this sounds external.

Ps; check the motor mount and motor bracket torque just in case. Cranks, peddles etc …

 

[Weeksy]

There HAS to be a tiny bit of play somewhere... sit on the back wheel, then reach forward to the midpoint of seat tube, below clamp and pull up in a sharp movement.... then again, again again... you'll notice it..

That said, i have had it on Treks where it's the bushing being undersized, on our Session DH it was supposed to be 30mm but was 29.12.... when we bought a 30mm one it went away. I'm aware of several others that were undersized too.
I've also had it where it's the Bontrager seatpost. But that's harder to diagnose as you'll need to remove the dropper, fit a static post and try it...

 

[Drumhitter]

There HAS to be a tiny bit of play somewhere... sit on the back wheel, then reach forward to the midpoint of seat tube, below clamp and pull up in a sharp movement.... then again, again again... you'll notice it..

That said, i have had it on Treks where it's the bushing being undersized, on our Session DH it was supposed to be 30mm but was 29.12.... when we bought a 30mm one it went away. I'm aware of several others that were undersized too.
I've also had it where it's the Bontrager seatpost. But that's harder to diagnose as you'll need to remove the dropper, fit a static post and try it...

This is such a FANTASTIC way to test for play! I've been working on bikes for 20 years, this (for me atleast) is one of the gold standard tips, free - no training - instantly easier.

Thanks both - it's the upper shock mount bearing, probably worth replacing those two, can't afford to replace others at the mo.

 

[Weeksy]

Blush. It's just what I do on the boys race DH Session as that's been a little flakey in terms of top bushes, but the shock we ran for 2nd half of the year was a bearing mount upper which was ace.