Rear Shock rebuild Qs. with pics

[EncyclopediaRonnie]

okay so between last motor rebuild and now i decided to powdercoat my frame. then decided id have a geez at my rear shock since its way to soft for jumping and i wanna jump lol. originally i thought the seal had blown out and wasn't gonna have much oil but when i pulled the shock down (after a search on here to find out how lol) it seems okay cause plenty oil came out and did not seem to be even slightly low the top guide bushing seems healthy the bladder dsnt seem torn and as far as i can see thers no damage well not from being out of oil etc.

could it be possible that its just old oil bad spring rate/weight low air level in shock that caused it to feel crappy? to change the seal i have to pull the shim stack/valve assembly off corect? is it worth me doing while its apart or just put it all back bleed and go for it?

also what bloudy oil do you use the clymer manual says nothing for rear shock only forks!!!

pics!!!

cheers hagen

 

[EncyclopediaRonnie]

rest of pics

 

[whenfoxforks-ruled]

My 97 used the same oil in the forks, as the rear shock, atf fluid. Did it still hold a charge of nitrogen also? Do you have the correct shock spring? You set the race sag, and check the static sag for set up, and that will tell you if the spring is correct?

 

[EncyclopediaRonnie]

i doubt verry much the spring is corect when i got the bikeit had sagged and the pre load wasnt adjusted the spring wasnt captive with the rear off the ground!!!!

it did hold charge but around the 100psi make it did not stay up near 145 but im thinking that may be a valve leak cause if the bladder was torn it wouldnt even hold 100

 

[EncyclopediaRonnie]

other advice any1?

 

[helio lucas]

there are on market specific oil for shocks, if i remember correctly the oil needs to hold up temperature better than fork oil.

this is what you need: http://www.mx-tech.com/?id=products&subcat=169

you really need to pull out the valve to change the seal. if you are carefull and let everything in the same order while you are disasembling, it´s all good and easy. pictures help a lot.
a seal is cheap enough not to change it.
mx tech can provide it as well :cool:

in the crappy feel thing, try to rebuild the shock, then test it adjusting the clickers as needed.
you don´t have to disasemble the shock to cahnge the spring.

 

[EncyclopediaRonnie]

good advice mate did the pics seem normal to you nothing scream repair me!!!

as for mx tech im in australia so shall have to source an aussie suplier but good starting point as far as what i require goes. im aware i can change spring without disasembly. i guess seeing how onli took me 20 mins to pull down leave seal for now then if it leaks start again lol hopefully new oil brings the feel right back.

onli concern is that it seems to be origonal still as the top nut has never been ground off its a 1993 bike so by the look it hasnt had a rough time as the bushing isnt molested

 

[helio lucas]

i don´t know if you can get parts on new zeland, but on australia there is a member named kiwi john that might help you looking for a good source of parts.

http://www.dirtrider.net/forums3/showthread.php?t=162080&highlight=dual+stage

try peskynz as he might be able to help you as well.

 

[EncyclopediaRonnie]

okay so sussed it all out i got oil and a new bladder now the trouble i have is i cant get it to bleed some1 help me here plz. it presses down and oil comes above the piston but it wont go back below just creates a massive vacume.

it seems asif the piston is blooked or something and oil is pushing bast the piston band

 

[helio lucas]

harder than it seem huh??? :laugh:

the oil flow is very slow. remember that is the function of the oil, slow down and absorve spring movement. remember as well the big leverage ratio on the swingarm to shock, now you may undertsand why the oil flow is very slow.
you have to pull the shaft very slowly and make sure there is absolutly no air below the piston.

my mx bike shocks go to suspension guys but on less than state of the art old bikes i usually do all the work until the shock is sealed, on a big plastic container full of oil. that way no air can get on the shock on the process of closing it.

does it make sense???

 

[EncyclopediaRonnie]

yeah but the mx tech instrusctions say to bleed the shock moving the rod up and down the motion mine dsnt move at all like you can pull up on it till it makes vacume leave it proped with timber come back 20mins later and it still will go back were it was before lifting it.

im wondering can the valving get blocked?

 

[Pete Payne]

Sounds like the rebound needle is stuck in the shaft preventing a free flow when you try to pull the shaft out during the bleed process.

 

[EncyclopediaRonnie]

Sounds like the rebound needle is stuck in the shaft preventing a free flow when you try to pull the shaft out during the bleed process.

sweet this sounds plausable how do i fix this? i dont wanna have to grind the stamp of the nut to pull assembly apart is teher away to free it?

 

[EncyclopediaRonnie]

not to worry pushed it down with a screw driver and now its bleed and reassembled i just hope it dsnt get stuck again :s


big big learning curve this has been lol but now ive done it and worked out what to and not to do and how stuff goes etc be more than confident doing it another 20 times.

cheers to all who helped

 

[Pete Payne]

It should be fine now.