Servicing Suntour XCR-120 LO forks

Northwind
Northwind Posts: 14,675
edited February 2009 in MTB workshop & tech
Gah... Just putting my kraken back together and the forks are acting up, very very stiff and inconsistent- the same big bump can cause them to use half the travel one time, then almost no movement the next. The rebound all seems to be working and they're returning to height normally, as far as I can tell. They were stored upright but I'll be honest and say they didn't get adequate servicing in the period before I took them off, I knew I was replacing them and didn't really intend to refit them but now I have enough parts to rebuild the kraken to stock so I'd like to get them moving, so that my brother can join us for rides.

I've tried to find a service manual for them, but no luck so far... And TBH they're probably not worth spending the cash on a professional service for, so I'm thinking I'll open them up and have a wee hoover out, see what happens. At worst I'll make them more broken :lol:

But, I can't find a manual, just an exploded diagram from the Suntour website. I've worked with motorbike suspension forks before but not modern bike forks, but it should be within my capacities, only things I'm concerned about is if there are seals, bushings or crush washers that have to be replaced on rebuild, and also what grade of oil to fill them with, since I can't find that anywhere.

Any advice on stripping etc would be much appreciated.
Uncompromising extremist

Comments

  • nicklouse
    nicklouse Posts: 50,675
    just open it up. you will be surprised how basic it is.


    IIRC there are no crush washers on the suntour forks.
    "Do not follow where the path may lead, Go instead where there is no path, and Leave a Trail."
    Parktools :?:SheldonBrown
  • Northwind
    Northwind Posts: 14,675
    Yeah, from the exploded diagram it looks approximately as complicated as a push-top pen :D Good to know on the replacable parts, thanks.
    Uncompromising extremist
  • Northwind
    Northwind Posts: 14,675
    Just a wee follow-on to say thanks, I have no idea what caused it but I'd misunderstood the symptoms- the fork wasn't stiff, it was stuck at the bottom of its stroke, I just hadn't realised. I undid the 2 bolts in the bottom of the fork leg, and immediately it returned to full length, and now seems to work fine. So, thanks for giving me the nerve to start undoing things :)
    Uncompromising extremist
  • So was it easy enough? I've just upgraded my XCR 100mm (to a Tora Race Solo Air :D), and wanna eBay it, but it's been really solid for a while now, so I wanna give it a clean up. Did you find any sort of instructions in the end, or is it pretty simple?

    PS I always break clicky pens...
  • Northwind
    Northwind Posts: 14,675
    Literally took 2 minutes. But it might not be the same as what's up with yours, i was expecting to have to totally strip them. Haven't a CLUE what was wrong with them :lol:
    Uncompromising extremist