Just bought a set if these secondhand and in great nick – super plush with LSC and HSC working fine. However, the rebound adjustment which has 30 clicks does very very little. It’s pogo fast from fastest to about 23 clicks in then it settles into something kind of rideable. Anyone have any tips? It’s been recently seeviced ( news skf seals and Motul oil change) Ive already let the air out twice and cycled the suspension to balance negative and positive air chambers. Fork feels lovely other than this.

Should mention, that it has 2.5w oil in

Should be 7.5wt oil. That’s your issue right there.

I have some AM ones and that has a similar number of clicks there is not a massive difference between each click but a big difference from one extreme to another

@getonyourbike – im glad you posted, i was reading your posts from last year on this which prove very helpful indeed! So I take it you settled on 7.5w after trying 2.5w first and then 5w? I imagine as they are open bath, the weight of the oil will change the dampening characteristics, am I right? I’m just trying to (hopefully) eliminate the possibility that the rebound circuit is shot.

I tried 2.5W first and felt the same as you, and was planning on changing them to 5Wt by mixing with 7.5Wt but never got round to it before I sold them.

If I did it again, I’d just got for 7.5Wt, Motul Factory Line which is which Jim at J-Tech uses, successfully.

I might give that a whirl. Although reading about VI or viscosity indexes is a pain as it sometimes feels contradictory to the W weight of the oil. Many people on forums reckon that BOS used a very low VI which is why in trying to match it, they found that the only oil easily sourced with a matching VI is the Motul 2.5. I don’t think there’s any proof that BOS used 2.5 in their proprietary oils. Plus, apparently low VI isn’t necessarily a good thing, it can mean the oil us more suceptible to thinning/thickening as temperatures change. I think I’ll play it safe and experiment with a 5w and a 7.5 w and see what happens.

BOS and Mad Elk cycles both sell the original oil on their sites.