Forks bottom out when bleeding

GSrick

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I've just replaced the seals on my 1100GS forks. Topped up with 470ml fork oil each side, but they bottom out when I bleed them, this can't be right.

I re-insert the stanchion , slowly lowering until the oil shows in the bleed screw but the stanchion has bottomed out by then.

There are no leaks and it look like a good job, but surely there must be some available movement downwards for the stanchion?
 
Maybe the O-rings in the bleed screws are shagged?

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I've just replaced the seals on my 1100GS forks. Topped up with 470ml fork oil each side, but they bottom out when I bleed them, this can't be right.

Yes you are right! You are doing it wrong!!!

I re-insert the stanchion , slowly lowering until the oil shows in the bleed screw but the stanchion has bottomed out by then
:blast :blast :blast

440 ML each side is PLENTY

You do NOT need to Bleed them! They are not shocks!!

They only control frontal alignment

You fit the bleed screw and its O ring at just about 30mm below the top yoke and GENTLY nip it up and complete the reinstallation

Basically that then stops seals blowing out

And you need air in there to compress as You cannot compress liquids as you have already found out :thumb

Where the heck did you find those instructions anyway????
 
The BMW Manual says
Fill quantity per fixed tube:
[RS/GS/R/RT] .................0.470 l (0.827 Imp. pints)

It also says , Bleed telescopic fork in no-load position. So I bled it until oil showed.
 
I think I see where I have gone wrong. I'm building these off the bike and I can see that the bleed screw seems to be to allow you to set the 30mm below top yoke. So I'll set them up when I am replacing them in the yokes. I have approached these as normal forks and they are not.
 
Fair enough

AS I said 440ml was what we put But I omitted that it was in the BM dealership where I worked ;)

Be VERY careful nipping up those pinch bolts I can;t remember the exact value but a guide for steel in alloy is to tighten to where you need to apply any pressure to the allen key or wrench to make the bolt turn, and from that point its an eighth to a maximum of a quarter of a turn

45 degrees to a maximum of 90Degrees

Good luck
 
The BMW Manual says
Fill quantity per fixed tube:
[RS/GS/R/RT] .................0.470 l (0.827 Imp. pints)

It also says , Bleed telescopic fork in no-load position. So I bled it until oil showed.

It's not bleeding as such. It's simply letting the trapped air out so it doesn't blow the seals.
Insert stanchions into sliders and do up bleed screw when the top of the legs are in line with the top yolk.
 
These are yolks

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These are yokes

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Sorry, couldn’t resist. I’m becoming Tarka aaaaaaaagh!
 
These are yolks

c1bb77e7559c80e7d7bc0731bb54494a.jpg


These are yokes

9e0bc878dfd704595c212bd1e1a93c86.jpg


Sorry, couldn’t resist. I’m becoming Tarka aaaaaaaagh!

Bloody predictive txt .. I won't edit it because it made me smile, so perhaps it may also put a smile on others feaces.
 
While we're talking forks. Does anyone know what the oil height measurement (if there is one) for the telelever forks?
I have a manual with the capacity but recently I swapped a seal on mine and I just wanted to top the oil up rather than take the forks right off and drain them.
I did some maths to try and work out the height but when I checked the other saide my calculated height was different to that one. It's possible the oil was wrong in that one anyway.
I've been riding it about and it seems fine but I just wondered....
 
For the ADV, in OEM CD ROM it says 650ml...

But I reckon 600ml would do it because there'll be some residue of old oil in there. I did mine a couple of months ago, subsequently had some evidence of oil on the stanchions. Steptoe suggested it could have been the grease on the new oil seals I fitted - seems very plausible . I mention this because I also wondered if I'd over filled them - despite my efforts to measure it the oil carefully, so a little oil was getting blown out. It's now all oil free and as it should be. But maybe of interest.

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Christ the Night!!!! they are just fork sliders to maintain alignment!!!!!

The drain plug is vertically up from the bottom of the fork You need to remove the wheel spindle to access these "bolts"

M8 x 18mm so a 6mm allen key! Probably better to support the front of the bike and slip out the wheel to prevent mess

Like I said 440 is "fine" for them its just to lube your upper stanchions sliding against the Teflon guides inside the legs

I always seal the bleed screw when the leg is about 30 to 50 mm below its fitted position on the top yoke


Official BMW workshop manual quoted

• Fill with oil. Capacity per fixed tube: .......... 0.47 l (0.82 Imp. pint/0.49 US quart)


Oil grade in telescopic fork: ............................BMW telescopic fork oil

Slippery either your finger was in the wrong place and got a 6 instead of a 4 and also you may have too much oil in your forks ?
 
Christ the Night!!!! they are just fork sliders to maintain alignment!!!!!

The drain plug is vertically up from the bottom of the fork You need to remove the wheel spindle to access these "bolts"

M8 x 18mm so a 6mm allen key! Probably better to support the front of the bike and slip out the wheel to prevent mess

Like I said 440 is "fine" for them its just to lube your upper stanchions sliding against the Teflon guides inside the legs

I always seal the bleed screw when the leg is about 30 to 50 mm below its fitted position on the top yoke


Official BMW workshop manual quoted



Slippery either your finger was in the wrong place and got a 6 instead of a 4 and also you may have too much oil in your forks ?
It's me doc. I forgot this was the 1100/1150 section

So to the op "IGNORE MY QUOTED QUANTITY ABOVE"

Actually, I'll just shut up

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It's me doc. I forgot this was the 1100/1150 section

So to the op "IGNORE MY QUOTED QUANTITY ABOVE"

Actually, I'll just shut up

Slippery Ole Son 1st Pints on me if we ever meet up!!!

You pay your Dues! You post away chum

I wasn;t aiming at you! You're sound!

Its the whole being "anal" thing but actually don;t know what they're doing that worries me

These are thee best Road motorcycles ever made

You can keep them going with chewing gum and string!!

SO!!! BE careful how you torque bolts Don;t over abuse them and they will care for you for years and years and years

AND If you are NOT SURE??? Always Always ask a question!!!!

Rise Safe! Keep Safe! Everyone!
 


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