Leaking Fork Seal....

BillyBoxer6

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Wife's little 2001 F650GS has a leaking Seal.
Anything I need to know before I attack it?
Any special Tips, Tools etc required?
TIA,
BB
 
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Before you do anything else, make sure it isn’t just caused by grit in the seal. Get one of these and give it a go. I reckon thousands of pounds have been wasted over the years replacing perfectly good seals.
 
Like with most others, Impact gun helps for the bottom bolt; You can make your own “seal driver” from the old seal/bits of drain pipe/ spent silicone sealant cartridge / even some stiff cardboard and a jubilee clip. If there is minor pitting/dings on the stanchions causing minor leaks, you can clean them then use superglue to fill them in and a sharp scalpel to smooth them down. I used plastic from a sparkling water bottle made into a tool to try to clean grit from old seals and eventually to drive new seals down the stanchion to avoid nicking them on corrosion/ding and making them leak again.

Oh, while you got them off, May as well get a rattle-can of smooth silver hamerite to tidy up the bottoms as they have inevitably corroded after 20 years. :) hamerite works fine for the waterpump cover too. I never saw one where the paint is not ‘orrible there. Hamerite is a decent match but takes forever to cure so extra care on reassembly red’d.

Inspect the bottoms, near the axle-holes for cracks carefully and do the axle back up / torque properly. I believe there was a batch where they were prone to braking off. Nasty, that. You can have a look here [ good site, that for most 650gs stuff.]

Good luck.
 
Thanks All, I'll have a go at cleaning them first.
It's odd really because they were fine when the Bike was Put to Bed last November.
She took it out for a bimble yesterday and the left one is Weeping badly, not just Misting.
 
Like with most others, Impact gun helps for the bottom bolt; You can make your own “seal driver” from the old seal/bits of drain pipe/ spent silicone sealant cartridge / even some stiff cardboard and a jubilee clip. If there is minor pitting/dings on the stanchions causing minor leaks, you can clean them then use superglue to fill them in and a sharp scalpel to smooth them down. I used plastic from a sparkling water bottle made into a tool to try to clean grit from old seals and eventually to drive new seals down the stanchion to avoid nicking them on corrosion/ding and making them leak again.

Oh, while you got them off, May as well get a rattle-can of smooth silver hamerite to tidy up the bottoms as they have inevitably corroded after 20 years. :) hamerite works fine for the waterpump cover too. I never saw one where the paint is not ‘orrible there. Hamerite is a decent match but takes forever to cure so extra care on reassembly red’d.

Inspect the bottoms, near the axle-holes for cracks carefully and do the axle back up / torque properly. I believe there was a batch where they were prone to braking off. Nasty, that. You can have a look here [ good site, that for most 650gs stuff.]

Good luck.

Doing mine atm, use a heat gun to warm the top of the slider that will assist in removal of oil seal and top bush. Mine are slightly rusty at the top of travel by bottom yolk, and experienced difficulty removing RHS stanchion from slider, suspect fork leg may be bent.
 
Did mine a few weeks back and they came apart without the need for any heat at all, thankfully.
They were filthy both inside and out, but with some Effort and Patience they came up like new.
The Bike's Handling has been absolutely transformed and she flew through the MOT last weekend without a single Advisory.
Now my Wife has decided that Pillion Riding is where it's at and the 650 is sadly up for sale.
It's a pity really but it'll make someone a cracking little Ride.
 

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Did mine a few weeks back and they came apart without the need for any heat at all, thankfully.
They were filthy both inside and out, but with some Effort and Patience they came up like new.
The Bike's Handling has been absolutely transformed and she flew through the MOT last weekend without a single Advisory.
Now my Wife has decided that Pillion Riding is where it's at and the 650 is sadly up for sale.
It's a pity really but it'll make someone a cracking little Ride.

Like those fork gaiters would you mind sharing the info?
 
Like those fork gaiters would you mind sharing the info?

Just a simple neoprene tube - Lyndon Poskitt sells them at a reasonable price on his site. They should however be over the top of the fork stanchion to offer full protection. These are usd forks but you see the point.

IMG_2057.jpg
 
Like those fork gaiters would you mind sharing the info?

Of course:


eBay item number:
272738788888

You cut them to length to suit but don't cut them too short or they can ride up the Stanchions when you stop (DAMHIK!).
Even if you do, they still protect the Fork whilst Riding but you have to pull them down when you stop or they look daft!
Well, I do because it bugs the cr@p out of me........
 
Just a simple neoprene tube - Lyndon Poskitt sells them at a reasonable price on his site. They should however be over the top of the fork stanchion to offer full protection. These are usd forks but you see the point.

View attachment 532492

For Info - the ones I've used are not wide enough to slip over the Lowers, but they were all I could find at the time.
 
The problem with not being able to slip them over the seal and stanchion is that they become a very effective crap trap, and force material into the seal making it fail sooner - as I experienced at a Hafren rally years ago.
 
The problem with not being able to slip them over the seal and stanchion is that they become a very effective crap trap, and force material into the seal making it fail sooner - as I experienced at a Hafren rally years ago.

Yes, it's less than ideal I know.
It's not a drama to switch them out at some point, but she's up for sale now so I'll leave that for the New Owner to Tinker with.....
 
Fork seals are quite easy to do. Replaced several over the years.
The oil inside them seems to get dirty very quickly even after a few hundred miles.
When separating the stantion from the lower leg, do it over a lawn or ground you don’t mind getting covered in oil!
Even after draining the fork some oil remains and it gets everywhere!
 
Fork seals are quite easy to do. Replaced several over the years.
The oil inside them seems to get dirty very quickly even after a few hundred miles.
When separating the stantion from the lower leg, do it over a lawn or ground you don’t mind getting covered in oil!
Even after draining the fork some oil remains and it gets everywhere!

I'll second that, 5 ft up the garage door in my case!
 


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