R65 GS:How can I take the forks off???

[Vincent]

Hi,
I've been trying to fit new forks gaiters on my 1991 R65 GS (not covered by my Haynes manual BMW Twins 1970 to 1988). I need to remove the forks. No problem for the bottom yoke pinch bolts, it's the top plug I cannot unscrewed.... Whatever I do with my 40mm spanner, it won't move. In the top plug there seems to be a big Allen section(not the filler plug which is further down), like a ring fitted in the top plug above the filler plug. See what I mean?? Does it need to come off first?

Thanks
Vincent

 

[Rob Farmer]

Vincent,

The allen head in the top of the fork is just for topping up the fork oil. If you are really struggling with the top nut just leave it alone and undo the large allen bolt at the bottom of the fork slider - draining the oil first. Once that is undone the slider can be removed. Slide the gaiter on, put the slider back on and refit the allen bolt. Remove the allen bolt from the top nut and use a funnel to refill with oil (takes a while).

If you just undo this bolt you can leave the stanchions, springs etc in the bike.

 

[Rob Farmer]

This is the damper mechanism that the bolt goes into. It's also the only thing stopping your fork slider from falling off. Once the sliders off you can just slide a gaiter up into position and put the lot back together again.

 

[MiGSel]

Here are the parts:

 

[Beemerboff]

If you have the Marzocchi forks on your 91 bike the tubes will slide out of the yokes with the nuts still on them - no need to touch anything except the clamp screws on the yokes. And the mudguard and callipers.

Do one side at a time , and mark the fork tube so it goes back the same way it was before you started , and the only thing you will have to reset is the level of the wheel spindle.

And if you haven't bought the boots yet fork out for OEM as the pattern ones don't last any time at all- don't ask.

 

[Rob Farmer]

Beemerhoff,

The R65 G/s kept the original forks from the 80G/s

 

[GS Weissbeer]

Hi,
I've been trying to fit new forks gaiters on my 1991 R65 GS (not covered by my Haynes manual BMW Twins 1970 to 1988). I need to remove the forks. No problem for the bottom yoke pinch bolts, it's the top plug I cannot unscrewed.... Whatever I do with my 40mm spanner, it won't move. In the top plug there seems to be a big Allen section(not the filler plug which is further down), like a ring fitted in the top plug above the filler plug. See what I mean?? Does it need to come off first?

Thanks
Vincent

I overhauled the forks on my '87 G/S last year and also had trouble loosening the 40mm top bolt. I used a VERY LARGE adjustable spanner and had help from a friend who held the spanner pressed down on the bolt so it didn't slip off the bolt. You might have luck by extending your spanner with a piece of pipe to get more momentum.

When removing the fork from the tripple clamps I had to use a wooden block and a large hammer to get the fork out.

When taking the bottom fork slider apart you have to remove the big lock ring at the bottom and that can be quite a challenge as well. I soaked it with WD40 and then used a good quality lock ring plier which was a very big help.

Inside my forks there was a lot of sludge and the oil looked like hot chocolade because water had entered through the leaking gaskets. So it's certainly worth doing an overhaul on the forks.

Hope you succeed

Dan

 

[Baffo]

The 80G/S and 65G/S forks are not exactly the same (!), see picture below. Nr's 22 en 25 need to be bolted against each other with an allen key and a spanner, this also locks/attaches the fork tube at the top yoke. Nr2 is only for the oil. So for tightening, allen key at 4 o-clock and spanner at 8 o clock and then push them both to 6 o-clock, or maybe this was to loosen it, I forgot, and then reverse it for etc

 

[Vincent]

Right! Brillant! Let's get on with it! Thanks a lot.
I'll give it a go from the bottom allen bolt. Just waiting for the rain to stop and get some hydraulic oil. I might come back for another shower of knowledge.
Thanks

 

[Voyager]

Hi,

I'm not sure about the R65; but on my 100GS and (previous) 80RT it is possible for the damper rod to turn as you try to tighten the bottom bolt on re-assembly.

I used an air-driven impact driver on a low setting to get the bolt to the point where the rod started to tighten.

Then the bolt can be torqued-up as normal.


Bob.

 

[Vincent]

I did as Rob advised; and no problem for the left fork, on and off with the new gaiter fitted and fork oil filled up. On the right fork (with the brake), it's doing what bob mentionned earlier, although it's happening when I try to take it off. I cannot unscrew the damper rod allen screw. The all damper rod is coming with it. Could I unscrew it by tightening the rod first? Which way does the rod tightened? Clockwise? Can it cause any damage? Any ideas?
Thanks
Vincent

 

[Vincent]

Hi Baffo,
I think I see what you mean... unfortunately I cannot open or find the picture you've attached. Are you talking about the bolt fitted with an allen ring at the top of the fork. Looks like the handlebars need to come off in order to fit the allen key, is that right?
I did as Dan advised for the left fork, no problem. But when I try on the right fork the all damper rod turn as try to unscrew it. so I think I'll try your way from the top.
Thanks
Vincent

 

[Baffo]

Can't find the edit button , but try this image

or these 2 URL's
And yes, handlebar needs to come off unfortunately

 

[Voyager]

On the right fork (with the brake), it's doing what bob mentionned earlier, although it's happening when I try to take it off. I cannot unscrew the damper rod allen screw. The all damper rod is coming with it. Could I unscrew it by tightening the rod first? Which way does the rod tightened? Clockwise? Can it cause any damage? Any ideas?
Thanks
Vincent

The damper rod won't unscrew it'll just turn forever. Its being extended by the fork spring and just runs in bushes within the stanchion.

An impact wrench will usually remove the bottom allan bolt as its action is so quick the damper rod doesn't have time to turn.

I've had the same problem with Mcpherson strut top mountings on cars.

If you don't have an air impact wrench - try a cordless drill in reverse and set to 'hammer'. That may have the same effect but you may need to cut the shank off an Allen Key to get it to fit the chuck or use a small bolt that has the same head size as the recess in the Allan bolt (from memory its 8mm).

Its these little 'niggles' that turn a simple job into an all-day event

Bob.

 

[Flipfly]

YOu could start a new trend, like the hoodies that have one leg rolled up on their trousers!!!!

Have you tried using a heat gun???

It worked wonders on the bolts on the RT, it may have been loctited

 

[Vincent]

Done!

Thanks a lot to you all. New gaiters are on! What a pain in the a....! took me a good ten hours. But hey, best way to learn for a newby. The bike is almost ready now: new Metzeller tyres fitted, new front brake pads, new battery, new spark plugs, tank resprayed with new filters, only need to sort out the exhaust silencer, give the engine a flush(any advice on that? I've got a 125ml MMP Motorcycle Motor Flush can. I was advised to drain 125ml of oil, add the MMP flush, run the engine on idle for 10 to 15 minutes, change the oil and oil filter. Is that right? Any risk of damaging the engine?), and ... I don't know actually, what else do you recon for a bike that hasn't run for ten years?
Anyway, thanks again, I'll be back...
Vincent