I have 2 leaking GPR dampers - is it possible to service them myself?

Discussion in 'Equipment' started by men8ifr, May 13, 2011.

  1. men8ifr

    men8ifr Been here awhile

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    Anyone else done this and was it successful?

    I don't think there is a rebuild kit for the GPR's i.e. seals but they are all plain O rings.

    Sending both of them off is a bit $$$ (£££) for some-one else to replace the orings.

    Both of the dampers are a few yesrs old but I'm a bit miffed they are both leaking.
    #1
  2. Mercury264

    Mercury264 Once you go Triple...

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    Mate had one leaking - he contacted them, not sure of the exact details but I am pretty sure they replaced it with a new one.
    #2
  3. Treewakr

    Treewakr throttle junkie

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    I've rebuilt my GPR damper a couple of times. They are pretty simple and straight forward. Just find the right size o-ring and you're good to go. Refilling the unit with oil is the most time consuming part. Add oil slowly and move the lever back and forth to work all the air bubbles out.

    Also, changing oil viscosity just a little lighter or heavier makes a big difference in performance!
    #3
  4. KTM450SX

    KTM450SX Been here awhile

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    Don't GPR's have a lifetime warranty?

    I only owned one but I thought it did. ( I don't use any stabalizers anymore )
    #4
  5. YamWOW!

    YamWOW! Been here awhile

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    #5
  6. men8ifr

    men8ifr Been here awhile

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    Yeah we get screwed over here (UK) a service is £55 ($80-90) in the US it's $25.

    I've never seen any mention of a first service free so I don't think we get that either.

    Better get the O ring kit out - I've tried once to repair one damper but it's still leakign though may be from the adjuster shaft - i did not replace the O rings on that i did not think it would leak there.

    It was a pain to get all the air out - I was going to try and submerge the unit in oil and re-assemble it should hopefully be easier.
    #6
  7. malsin

    malsin Adventurer

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    My GPR is leaking yet again, after two free redos by GPR after I paid for service (with me paying the shipping so not really free). Unit lasted two years before it leaked. Now it leaks on day one of riding after getting it back. Each

    Here are two items that may help anyone else that comes across this thread.

    Picture of a GPR disassembled and barebones instructions. I'm less nervous about trying the service myself. I figured I would open the top and have springs flying everywhere ...
    http://www.georgiaoffroad.com/forums/viewtopic.php?f=17&t=47520

    GPR refill and bleeding instructions that they used to have on their site. I saved a copy way back when and now it isn't posted anymore. So here is my copy of their document:
    http://home.everestkc.net/malsin/Motorcycle/rfs/GPRAirBleedingInstr.pdf
    #7
  8. luv2lean

    luv2lean not lost til out of gas

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    Thanks Malsin for the useful instructions. It looks fairly simple. Anybody found a good source for the o-rings?
    #8
  9. ndrordr

    ndrordr n00b

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    Anyone that's done this know what the size of all the little allen screws is? I am in need of re-oringing mine, but none of my metric or sae allen wrenches fit.

    Any help is appreciated.

    Rob
    #9
  10. men8ifr

    men8ifr Been here awhile

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    I will have to try again - I'll try to take some pics and let you know O ring sizes etc.

    Re the allen bolts all I know is it's a U.S size and was standard in a small set of allen heads I got in the UK so should be very easy to find in the U.S. Also re the O rings a $10 O ring kit with say 20-30 different sizes should have all you need.

    Regarding the re-filling and getting air out all I do is fill as much as possible and re-assemble then turn the unit upside down, remove the 2 small silver cross head screws and pour a bit of oil in each then move the damper arm slowly left to right adding oil at each screwhead for 20min and all teh air should be out. Check by setting the damping to max and moving the arm by hand left to right - you should feel no free play in the arm around the centre.
    #10
  11. de Razendebol

    de Razendebol n00b

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    Okay, it is easy diy but they don't sell the o ring kit, just measure the seize with a calipher,
    all standard seize, fill oil with a syringe, good examples on you tube how to do it
    got mine gpr 4v dirt 2 years and start leakingwill take it apart and post the seize
    #11
  12. Roland3

    Roland3 Been here awhile

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    Any update on the oring sizes? I am doing my gpr 4 now and it is simple but would be handy to have actual sizes on record. I am using ATF fluid and it seems to work good. I think the viscosity is around 7 wt. I will update If I get actual oring sizes

    Update: nothing here is really confirmed but here is what I am using, I will update on results:

    large center oring that top plate goes over is a #144 oring - .103 thick, 2.693 OD
    I used a 2-029 on the center hub 1/16 ø, 1.625 OD
    2 small orings on the dial - forgot to measure size, will update
    Bleeding the air out can be difficult, I happen to have a tub of used fork oil that was in good condition still, so I filled the inside as much as possible, then took 2 screw out of the ends and held it under the oil and worked it back and forth

    Also check that the pivot arm bottom is resting on the stud post shoulders, Mine had a gap and I noticed the arm flexing up and down on #8 setting, This is when the oil would leak out.
    #12
  13. sicks90

    sicks90 n00b

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    Thanks Roland3 for the information!

    I have a GPRv4 and it's leaking again, for the third time in 2 years! I'd rather not have to pay for shipping every time this happens, so I'm going to try the rebuild myself.

    I wrote to GPR and asked for advice about o-ring size and oil weight, but they replied saying, "sorry the o-rings are not something you can buy", and, "the oil is 1wt". I can understand that they would rather fix these things themselves, or subcontract it out like they've done before in Canada, but I'd really prefer not going without a stabilizer every few months because of an o-ring leak.

    Roland3, where did you find/purchase the o-rings, are they a special type, and can you clarify the sizes please? You mentioned a #144 and .103 "somethings" thick for the main one, and then a different naming convention of 2-029 and 1/16 "something" for the hub.

    Sorry for all the questions, I'm new to the world of o-rings!
    #13
  14. Roland3

    Roland3 Been here awhile

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    Ok, here is an update:
    I never fully got it to stop leaking and sent it to GPR along with a friends. They ended up replacing the entire body of the unit ( actually on both units we sent in), as I guess it was worn out and the problem was not really the orings. I recall reading somewhere there was some sort of recall on the early models but not sure if there is any truth to that. I got the unit back and it doesnt leak at all.

    my stabilizer was purchased in 2010 with the bike as far as I can tell, I wasn't the original purchaser. And not sure if it was a mistake or intentional but they did not charge us anything on either of them.

    The orings I listed are as close to what was in the unit as I can find, the problem is the orings are worn and stretch and difficult to measure so I did the best i could. You need to look at an oring chart. nobody locally like hardware stores had the sizes I had to order them from online suppliers. One seller on EBay had individual orings if you search the size. 2-029 and 2-144. I believe the 1st number has to do with the material or grade of the oring and the second number is size. so use 2-XXX , or 1 -xxx they will be same dimensions. Sorry this is not much help as I pretty much gave up after replacing the orings about 4 times. one thing on my unit I noticed after several attempts at changing the oil is the oil quickly turned grey, and it was from the aluminum wearing on the center hub

    Aslo I will add if you do attempt, the best way to get all the air out of the unit which is important is to hold it submerged in oil withe the little end screws removed one at a time and just work it back and forth, little bubbles will keep coming out. I only was able to do this because i had a half gallon tub of fork oil I drained out of my forks and it was nice and clean.
    attmeping to just bleed it by hand and keep adding oil in the little screw holes is a painfull waste of time.
    upload_2017-4-12_11-49-57.png
    #14
  15. sicks90

    sicks90 n00b

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    Thanks Roland3, I'm going to reach out to GPR again to see if they will do something with it before I do. Failing that, I might just save my pennies and move to a Scotts. Most of the guys I ride with use Scotts and never seem to have this problem.
    #15
  16. Roland3

    Roland3 Been here awhile

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    yes, I am leaning towards Scotts if I ever purchase another one. However I will add this; on the phone and thru Email their customer service was short and not very accommodating, just saying to send it in. But when we sent the units in, they got them back to us in NY in about a week and charged us nothing at all.
    #16