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kro
17th March 2006, 21:30
My DR has zero rear suspension. The spring seems ok, but the shock is just a big spongy mess, with no damping etc etc.

It looks as though the shock could be dismantled, and messed with. Would the replacement of the oil, and gas recharging make any difference?. I only ride once a week, for about 6 hours at a time, and really low key adventure riding, with a bit of stropping up and down some rutty tracks/hills.

I am loathed to spend money on it, its just a hobby bike. I have the tools and the mechanical aptitude, but don't want to launch into something thats not gonna make it any better.

Thanks troops.

crazyxr250rider
17th March 2006, 21:36
Buy a RMX shock.

Brian d marge
18th March 2006, 01:24
Its not that hard to rebuild a rear shock, I do mine every hand full of meetings, This time round I replaced all the bump stop, seals etc so was a little more expensive than usual, but no that much so

if you are careful you can do it yourself. and take it to a dealer to get recharged with nitogen .

Stephen

cowpoos
18th March 2006, 09:27
very typical of dr's....god knows why....I got a new rear shock under warrenty on my drz 250....and was told by the dealer that quite a few have failed aswell....apparently a weak bladder is the main weakness in the shock...

kro
18th March 2006, 09:39
Thanks troops. I might launch into it, and see what happens.

Brian d marge
18th March 2006, 20:29
if you need any photos or pictures to help , I have my rear shock apart again. Trying a modded low speed horiface.

Stephen

kro
20th March 2006, 06:34
Sorry Brian D, I lost track of this thread. Thanks for the offer, I will try get a schematic or similar off the net. My one is covered in oil, the shaft, the lower body, the spring. I'm starting to wonder if there's any oil left in the old shock at all. There is definitely a removeable cap on the thing, so I'm going in tonight, and inspecting the "damage".

Wellyman
21st March 2006, 17:54
Sorry Brian D, I lost track of this thread. Thanks for the offer, I will try get a schematic or similar off the net. My one is covered in oil, the shaft, the lower body, the spring. I'm starting to wonder if there's any oil left in the old shock at all. There is definitely a removeable cap on the thing, so I'm going in tonight, and inspecting the "damage".

O dear all that oil is not a good sign! I think it would now be empty judging on what you said and that is a disater. many vitals inside could be damaged. I would get an expert on it (your local shop) or best be would be a suspension Guru (Tjbbe Bruin,Norm Cobb, Browny at Colemans).
WM

kro
22nd March 2006, 22:00
dammit, don't say that, I just got my sidestand fixed, and I'm taking zeRax out on sunday, for a ride, and can't be worrying about such things.

grrr, now I have more work to do.

kro
2nd April 2006, 20:34
Just getting back to this.... is there a speacial oil to use in the rear shock?

Brian d marge
2nd April 2006, 20:42
yes the thinner the better .... depends on the speed at which you want your shock to move.

ATF is a touch to hard, I used it in me CR but it slowed the shock to much and I lost traction you may not notice if you are just trail riding

Stephen

Wellyman
2nd April 2006, 21:16
Aren't you supposed to use fork oil, they can be used for forks and shocks I think. but ain't sure, best bet is to ring a shop to ask.
WM

kro
2nd April 2006, 21:41
My riding is almost exclusively forest work, i.e loose clay, some rocky hills, some loose dirt, and a fair bit of gravel road. I dont race at all (yet), and if I did, it would be low key VMX if at all.

I am not going hard out at all, I just want some traction, of which I have very little at the moment.

Brian d marge
2nd April 2006, 23:47
If you dont mind waiting untill tomorow I am picking up some oil myself , There is quite a range to chose from so I can tell you some more!

Shock oil has a lot of anti foaming sstuff in it, which is why you can use atf , I use atf in the gearbox ( good for 1 race session only), front forks , and as I said the rear , but it was to hard in the rear put that one down to experience !
I do have a list somewhere with the viscositys , I pinched it off a web site some where! I can find if needed.

stephen

kro
3rd April 2006, 06:32
Thank you, I will watch this space with antici...............pation.

kro
10th April 2006, 15:51
Err, Mr D'Marge sir, I pulled the shock to bits, I wager she had all of 4 tablespoons of oil in it total, including reservoir.

I have stripped, flushed, and cleaned it up big time, but dont know how much oil to put back in it. I bought some cheapo Castrol 10w fork oik, which says it can be used for rear shocks too.

The shock is actually quite trick for an old 82 (assuming its original), and has four settings, first 3 are gradual increases in centre shaft orifice size, and 4th looks like a lock out of some description, with no hole on this setting. I never saw the dial thingy on it that changes the settings, as its on the swingarm end of the head, and was full of years of crud, thus making it invisible, and besides which, with no oil in it, it would have made no diff whatsoever.

Mine has remote reservoir too, do I need to flush and clean this too?.

Thanks guys/gals.

Brian d marge
11th April 2006, 13:40
Sorry my apalogies I fogot. I have been getting a workshop together and have been rather busy.

10 w will be fine a bit on the thick side but as you are not racing the thing I doubt if you will notice the difference in drive ,

The holes you are talking about are your low ( shaft) speed damping adjustment. Showa move a wedge which gradually covers the holes making the oil hydraulic lock sooner.

The remote chamber needs to be flushed, cause there may be little bits of rubber from the bladder

undo the valve in the middle release the Nitrogen using a lond socket put it over the valve and tap down , u will expose a circlip.

When reassembling the shock put oil in first. tapping the side of shock to remove air bubbles and then inflate with AIR to about 30 psi to seat everything ....work the shock a few times then remove the air and Replace with nitrogen at about 150 psi depending on what bottoming ressitance you want.

Stephen

Pm if you are wondering, very sorry for not getting back I have been flat out and simply fogot sorry bout that .

kro
11th April 2006, 19:03
Thanks dude, I have the DR back together, and the difference is astounding. The most notable thing is my front wheel doesnt lift so easy, I guess that coz the rear wheel aint squatting hard down every time I accelarate.

I filled the shock, and the reservoir, primed them, and left them over night, for all the air to rise to the top, where I bled it off. There were no "bladders" involved, is this a problem?.

I took half the bike to bits, even hauled the swingy off, and re lubed the bearings, and generally tarted it all up. I set the preload up a bit, seeing as Im a fact bastard too, and like I said, the difference is amazing.

Wellyman
11th April 2006, 19:23
Err, Mr D'Marge sir, I pulled the shock to bits, I wager she had all of 4 tablespoons of oil in it total, including reservoir.

I have stripped, flushed, and cleaned it up big time, but dont know how much oil to put back in it. I bought some cheapo Castrol 10w fork oik, which says it can be used for rear shocks too.

The shock is actually quite trick for an old 82 (assuming its original), and has four settings, first 3 are gradual increases in centre shaft orifice size, and 4th looks like a lock out of some description, with no hole on this setting. I never saw the dial thingy on it that changes the settings, as its on the swingarm end of the head, and was full of years of crud, thus making it invisible, and besides which, with no oil in it, it would have made no diff whatsoever.

Mine has remote reservoir too, do I need to flush and clean this too?.

Thanks guys/gals.


Lack of oil! now wonder why it isn't working.greasing the suspension bearings etc is also a good way to make the suspension work better, I do it regularly with my bike.
WM