My year old 09 Fox RP23 shock has a dead/flat spot at the top of the stroke. I'd say this flat spot jumps about 5mm before it compresses in the normal fashion. I'd noticed when out on my last ride that the rear shock isn't feeling quite as plush and sensitive as normal, which is why I bent down to have a look…

I thought I'd ask folks on here if there's anything I can try before I send it off for a service. I wouldn't be surprised if there was something broken or worn in there, as it's had quite a hard life this year (including a trip to the Pyrenees).

There's no oil or air leaking from it and it's not making any funny noises, it just feels like something's worn out on it (which it probably is.

Cheers.

I had the same thing happen on my '08 RP23 from an Orange 5 after 7 months use. Sent back to Mojo under warranty, no explanation of cause but is now better than was new

That sounds like some of the damping oil has leaked (probably into the air can which is why you've not seen any) meaning that the top of the stroke is in air rather than oil – eg no damping – which is why it 'jumps'.

At least that's what your description suggests. Can you clarify 'top of the stroke' – is that top out? Also 'flat spot' and 'jumps' – do you mean that there's basically no damping so it just moves very freely/quickly?

If it was the same as mine, the first 5mm of travel had no resistance at all. when you lifted the bike, the swing arm moved to max extension on the shock, as soon as the weight of the bike was put on the shock it moved the 5mm and then met resistance with a sort of clunk- best descrition I can give! And no, it wasn't the bushings and yes the LBS wasn't sure either hence the shock of to Mojo. All credit to both LBS and Mojo- the shock came off frame on Saturday about 11 am, was back on the bike by Wednesday lunchtime.

New seals all round might help, £not much and easy to do.

Mine was the same; it is something to do with the sweeper seal guide washers (the plastic washers between the can and the seal)

I sent it back to MOJO and they said that is the design of the shock and it is nothing to worry about (my ass was my thoughts), I then contacted TF Tuning and they told me about the seal plastic bits. This is a relatively easy problem to fix, all you need is the plastic bits out of the Specialized service kit. I have since found out that Mojo are now doing the service kit with the thicker plastic bits in.

If you get the 2010 service kit, it should sort the problem.

Same happend to me – Fox told me it was fine after a warranty return – they serviced it 3 months ago and is still doing the same – So who knows – I give up 🙂

Thanks for the replies. 🙂

To Clubber: Everyone else on this thread has described the problem with it clearer than me. It's basically a lack of resistance before and weight has been put onto it. No damping whatsoever.

I think I'll send it off to be serviced. I'm not much of a mechanic (as you probably already realised by basically written description of the problem) and I'll probably ruin it if I have a go myself.

Does the 2010 service kit include the new Boost Valve can or do I have to pay extra for that? Also, if I do have to pay extra, is it worth the money? I've heard it makes the stroke more linear but I'm not sure I'll feel it as I suspect it's a bit of a gimmick…

Cheers!