Possible to put oil back in 83 GS750ES monoshock?

[baz666]

Hello all,
Now that I've sorted my engine problems, I wanted to change the rear shock, which is pretty tired. I have a low mileage shock from another GS750ES but the hose that runs off the shock to the adjuster with the big round knob was twisted so much it split and its oil leaked out.
The hose and adjuster on my existing monoshock are in good shape and I plan to use them but is it possible to fill the replacement shock with oil?
thanks in advance,
baz

[Macmatic]

Hello all,
Now that I've sorted my engine problems, I wanted to change the rear shock, which is pretty tired. I have a low mileage shock from another GS750ES but the hose that runs off the shock to the adjuster with the big round knob was twisted so much it split and its oil leaked out.
The hose and adjuster on my existing monoshock are in good shape and I plan to use them but is it possible to fill the replacement shock with oil?
thanks in advance,
baz

Yeah, this is totally possible. Think of the adjuster as a master cylinder and the shock as a caliper.
When I first did mine the adjuster had a lot of gunk in it so I took the whole thing apart and cleaned it out then blew some brake cleaner down the hose while it was free of the shock. I don't know if this was smart or not but I also shot brake parts cleaner into the shock to clean that and it's been fine for the last 12,000mi or so.

Let me know if you need more detailed instructions but basically what I did was put the shock in a vice and fill the reservoir, then fill the hose and attach it while keeping a finger over one end to keep the fluid from running out. Finally draw the adjuster plunger all the way back, ALL the way, and fill that. There is a little extra room and I used that to bleed the hose again by cracking it loose at the shock.

Be careful with the adjuster knob! It's a weak design and both of mine got ruined as far as the intended design when the plunger took a little more force than normal to turn. Very little of the knob grips the adjuster shaft. Putting in a longer allen head bolt with some blue locktite has worked fine for the last couple of years though so don't worry if the knob cracks. And don't sweat it if you get a little air in there, it's only the preload and I don't think I've ever set mine to more than 3.5-4 even fully loaded down with a weeks camping gear and food/water. So if you have a little air you'll be fine.

I used ATE Super Blue because that's what I had around the shelf but DOT 3 would probably be fine too.

/\/\ac

[baz666]

Thanks for the instructions. So, if I understand correctly, this pre-load thingamabob uses brake fluid. It sounds sort of like the anti-dive contraption on the front fork.
As for the reservoir with the adjuster knob, I fill that too? I don't have it in front of me but I remember there is a little red indicator behind a plexiglas window in the adjuster body. On the window itself is inscribed the numbers 1 through 5 with white lines. Are these to indicate how much pre-load you're adding to the bike's suspension?

thanks for the help,
baz

[Macmatic]

Thanks for the instructions. So, if I understand correctly, this pre-load thingamabob uses brake fluid. It sounds sort of like the anti-dive contraption on the front fork.
As for the reservoir with the adjuster knob, I fill that too? I don't have it in front of me but I remember there is a little red indicator behind a plexiglas window in the adjuster body. On the window itself is inscribed the numbers 1 through 5 with white lines. Are these to indicate how much pre-load you're adding to the bike's suspension?


baz

That thing with the red indicator is the adjuster. Pretty much what you want to do is get that, the hose and the reservoir in the shock full of fluid and without air. I don't know what the OEM fluid was but I used DOT 4 and it's lasted 5+ years.
I took mine all apart and cleaned the gunk out before I filled it, yours may not be as bad.

This really isn't like the anti-dive on the forks at all. You use this and the 1-4 dampening adjuster to compensate for different loads and riding conditions. The system still works great on my bike from riding to VT with a fully loaded bike last weekend, to just me and the bike on some sporty rides to those last 50mi home at the end of a 750 mile trip when I wanted things nice and cushy.

/\/\ac

[Clone]

I am pretty sure the manual shows how to recharge the preload. I will look for the manual.
But if I recall, it is a process of draining the old oil out of the proload body, then refil. as well as screw down the adjuster and then filling that up as well by removing load

[SVSooke]

I am pretty sure the manual shows how to recharge the preload. I will look for the manual.
But if I recall, it is a process of draining the old oil out of the proload body, then refil. as well as screw down the adjuster and then filling that up as well by removing load

Which manual?Never seen it in the one I downloaded from BassCliff.Just rechecked,nothing I could see.