x9 500SL Fork Seals - tips on removal

[oldyella]

I have just changed the fork seals on my 500SL. There are lots of helpful hints in the forum but I hope this combines them into one. I didnt remove any panels or clocks to remove the forks.
Step 1 - remove front wheel and mudguard, remove the calipers from the forks (you can leave them on their mounting plates)
Step 2 - loosen allen key bolt at bottom of fork - if it just keeps turning round dont worry. You can use an air wrench if available to loosen allen key bolt - if not available proceed to step 3.
Step 3 - remove fork leg. Okay  - this isnt straightforward. Firstly you need to undo the 2 bolts holding the fork leg in the yoke - not a lot of room but can be reached with a 12mm spanner. Rremove the top cap on the fork tube - the cap has a 10mm allen key slot in it - but you cant get a full size allen key or socket in position. I used a short "stub" of allen key and removed cap with a 10mm ratchet spanner. Once the cap is removed the fork leg can be withdrawn downwards.
The yoke has a ridge at the top so the fork can only be pushed up so far (hence you cant remove the fork with cap in place.)
Step 4 - empty the fork of old oil - it is messy as if you turn the fork upside down the inner spring falls out bringing with it oil. If you managed to undo the bottom allen key bolt remove it completely and you can seperate the fork sections.
Step 5 - if like mine the bolt was just turning in the lower fork leg - try this. I read on the forum that a Haynes manual recommended compressing the forks to hold the internals together to allow the allen key bolt to be removed. Tricky if there is just you and you would have to reassemble the front end of the scoot. I opted to compress the fork off the scoot. Screw the top cap back in and put in the wheel spindle in its original place. With the fork then upside down I wrapped a ratchet strap round the fork top and around the wheel spindle and tightened the strap. I could then remove the allen key bolt after a few hits with an impact driver. Then split the fork into its two parts. Be sure the internals go back as they come out.
Alternatively - the allen key bolt moves as the internal damper is free moving in the fork. To access internal damper remove fork cap, remove spring. The internal damper has a 12mm allen key slot in it (I didnt have a key this size so cant confirm size is correct) - a 12mm 1/4 drive socket should be able to reach the internal damper.
Step 6 - with the fork now seperated into its component parts you need to remove the old seal. Previous experience has shown me this can be tricky as they dont simply pop out when a scewdriver is waved at them! Firstly remove the dust seal then the wire circlip holding the seal in. The forum suggests there should be a washer under the circlip (or even under the seal but none was present on mine) I did try levering out the old seal with a screwdriver but it looked like I was just marking the fork surface.
I then applied heat to the top of the fork tube - enough to warm and expand the metal and tried again with the screwdriver - the seal popped out.
Step 7 - replace the seal. - I centred mine with a big socket and a rubber mallet to seat the seal below the circlip line.I did this with the fork cold.

Reassembly is the reverse procedure. I added new fork oil 90cc of 20W fork oil.

Hope this helps

[Dave Milnes]

Very helpful especially the tip for budging a stuck bottom drain bolt.
I found though on Evo struts if you prize off the seal dust cap and remove the circlip and washer, then jerk the two parts apart the seal pops out with the chrome tube as the inner bearing snags it but yours sound like they were well stuck in anyway so this may not have happened.
The Evo also doesn't have top screw caps but a thin wire circlip in an outer groove that stops the fork dropping down out of the yoke, just push the leg up peel it out then the leg drops clear. You cannot remove the inner white top cap easily so you have to get that drain bolt out one way or another.
If you do need to get the top cap out to get to the inner allen socket, the white cap presses down against a spring to reveal another wire circlip then it should come out BUT water gets in there and rusts the circlip and inside of the leg so the cap becomes firmly wedged and refuses to come back up and out and you make a right mess of it trying to prize it out, so best leave it alone.
If you can't get it out you have to refill through the seal gap before drifting the new seal back down around the top chrome tube and use a long tube as a drift. Plastic drain pipe works OK.

[ronoc88]

Gents any advise for quantity of oil per leg please. Both of kine were leaking so I cant rely on measuring the existing qty.

The web suggested 20w. My local bike shop only stocks 10w should I drive .... or wait for the correct stuff to come in?

Advice appreciated

Conor

[Mr.Chips]

If you don't want to wait for an answer, go to the Home Page and put 'fork oil' in the Search box; there are zillions of posts to trawl through.

 

[Dave Milnes]

Stick with 20W. A few have experimented in the past to try to improve the damping and nearly all ended up back with 20W.

[ronoc88]

Thanks gents, I had done a search and read a lot before starting. but this just confused me more... Most posts seem to recommend 90ml per leg SAE 20W oil. The manual has this comment
'Front fork
This is to inform you that, starting from frame no. ZAPM2700004008122, the front fork has been replaced to improve comfort. The new suspension differs from the previous one for a different stiffness
of the springs and a higher quantity of oil: from 268 cc to 273 cc ± 2 cc of Selenia Fork 7.5 W'

My frame number is before that mentioned in th manual so I assumemed that 90ml per leg was correct. But.. then the one leg on mine that was not leaking bad, had 220ml of oil when drained.

At that stage I had the 10W in hand so said worth a try . I have put in 230ml of 10W. I have not ridden to far on it yet. But so far the fork feels plush. The only concern is that, I can now with force make it bottom out, where im sure I could not do this before. 

Thanks

Conor

[ronoc88]

P.S I now have the 20W so after a few rides will likely change back to 20W. Just wondering if the qty or viscosity of the  oil is important when it comes to bottoming out?

Thanks

Conor