GS100 PD possible wedgie ?

[Captain Black]

Is it possible to perform a rear wheel wedgie on my PD ?

The reason I ask is I want to drain the front fork oil , but you can't get it all out ( any sludge ) at the very bottom just through the ordinary small drain holes.
My plan was to wedge the rear wheel so the front is as firm as possible on the ground then remove the bottom bolts that attach to the fork rods.

I can then do a flush from up top with brake cleaner.

Is this an act of overkill or just madness ?

Having replaced the fork seals on my lads 80 Basic I was amazed by the amount of shit in the bottom, or maybe its just where it accumulates without any detrimental effect on a fork oil change / performance ?


Edit; or do one fork leg at a time ?

 

[JohnnyBoxer]

Just drop the effing forks out of the clamps totally & do the job properly

Centrestand & block the sump

 

[Captain Black]

Just drop the effing forks out of the clamps totally & do the job properly

Centrestand & block the sump

Don't wanna damage my seals ....

Why take the forks out ?

 

[solidstate100]

And I certainly would NOT be using brake cleaner in my (unassembled) forks - how are you going to be sure that you have flushed all THAT out given that you cant completely 100% drain the forks anyway.

Personally I would change the oil in the normal way and not overcomplicate/overthink/overcompensate for it. Save the sludge scraping for when you DO need to strip the forks - BTW you would be amazed just how quickly the compression side of the forks kill/contaminate/sludge up the oil - I have recently been on a voyage of discovery (or more correctly a fu*king PITA ball ache hassle) with forks/springs/oils and can tell you that having changed the oil for fresh and then changed it for a different weight after a 50 mile ride (more than once BTW) that the oils were already significantly degrading/blackening. And yes fully synthetic to dino oil types. So dont worry about it.

 

[Captain Black]

And I certainly would NOT be using brake cleaner in my (unassembled) forks - how are you going to be sure that you have flushed all THAT out given that you cant completely 100% drain the forks anyway.

Personally I would change the oil in the normal way and not overcomplicate/overthink/overcompensate for it. Save the sludge scraping for when you DO need to strip the forks - BTW you would be amazed just how quickly the compression side of the forks kill/contaminate/sludge up the oil - I have recently been on a voyage of discovery (or more correctly a fu*king PITA ball ache hassle) with forks/springs/oils and can tell you that having changed the oil for fresh and then changed it for a different weight after a 50 mile ride (more than once BTW) that the oils were already significantly degrading/blackening. And yes fully synthetic to dino oil types. So dont worry about it.

You may have a point, it was just seeing the amounts of sludge in the lower sliders on the 80 Basic had me thinking ill do a good flush. Perhaps leave it on the PD until the sliders need to come off for fork seals. Maybe BMW should have put the little drain screws further down the leg ? Unless they see that lower part as an intended sludge trap perhaps.
Brake cleaner is lovely stuff for these sorts of jobs , it cleans all that crap out perfectly evaporates and leaves a good clean start for the new oil.
I assume the grey sludge is nothing more than metallic colouring from the springs etc.

I do enjoy fiddling with these old airheads though.

 

[Beemerboff]

You could get a liter of cheap ATF , put half in each fork leg, run with it a week of so then drain it and see what comes out.
You will find out if there is a lot of sludge left after normal draining ,and also what under damped forks feel like, as ATF is on the thin side for GS forks.
You will also have put in 50 cc too much, so you will find out what difference reducing the air gap above the oil makes, and you might even like it - my Funduro forks feel better with a bit more suspension fluid in them.