Sealing fork casting to chrome

[rhill]

Ran the new bike for 3 sessions over the weekend; it turns out the one fork was leaking between chrome and casting, so they came back off. (the second one had a tiny weep) The fork that was leaking has silicone (I think) on the threads of the chrome. The one that was nearly dry, didn't seem to have much of anything. Any recommendations for reassembly?

Link to a few photos: https://goo.gl/photos/wkjo5Z4bwqdgsBPc7

I've heard that most forks have a seal and red loc-tite on the threads. These have no seal at the bottom and they are secured with a set screw. As the fork is screwed into the leg, it actually secures the damping rod into the casting. Without the chrome tube in place, the damping rod jiggles around free, only retained by the little spanner screw where the compression screw is normally located.....which will be removed tonight for a full inspection.

 

[rhill]

Just added two photos to the album that look down into the casting. You can see an aluminum flange with spanner holes. The flange is attached to the damping tube....it is loose right now, but when the chrome is tightened down, it secures the flange and rod in place.

 

[Emerson]

quit tinkering with stuff and just ride it!!!

 

[rhill]

quit tinkering with stuff and just ride it!!!

That's the plan for Sunday and Monday at Mid-O....if I can get the forks to seal up and stop leaking. If I have to, I'll put the stock forks back together to ride the thing.

 

[rhill]

so here is an exploded view of the fork broken down.

the tiny little o-ring bottom rightt (believe it is 2mm thick x 42mm ID) was chewed up on one fork and the other was completely severed.....I'd put money someone removed the cartridge previously without first removing that O-ring.

It is really fun to put that little guy into the casting after the cartridge is installed, and that is the only way I could figure avoiding pinching & damaging the o-ring. Nothing a few minutes with some dental picks couldn't take care of.

Tested the seal on the fork by wrapping a tie-down strap and compressing it almost fully and leaving it sit for a couple hours....nothing leaked.

The bike is now back together, but I'm thinking it is going to need to come back apart AGAIN, because the compression dampening is not functioning properly. These Race-Tech cartridges separate compression and rebound damping into individual forks. The rebound fork works great, but I can turn compression fully out to fully in and it doesn't reflect (much) in the damping.

The odd thing, with the cap off and manually moving the damping rod(as pictured) the damping changes with pressure to the internal rod. When fully assembled, the compression damping adjustment does little. Bounced the bike and got like 90 mm of travel with the compression fully out and 85 with it fully in. I'd expect it to nearly hydraulically lock like every other set of forks I've bounced in the past...the rebound settings work as expected.

Just for fun, took a couple pics of my homebrew fork fluid height gauge

 

[wmhjr]

I actually thought somebody hacked your account and was posting pics in your name because I didn't see any zip ties in the photo anywhere. But then I did see there was at least one on the fork tube so I could rest easy knowing your account was safe.

 

[rhill]

I actually thought somebody hacked your account and was posting pics in your name because I didn't see any zip ties in the photo anywhere. But then I did see there was at least one on the fork tube so I could rest easy knowing your account was safe.

Loading the photos, I saw that zip tie on the fork leg and had this "Doh!" premonition that it wouldn't go unnoticed.

 

[vinny337]

That's the plan for Sunday and Monday at Mid-O....if I can get the forks to seal up and stop leaking. If I have to, I'll put the stock forks back together to ride the thing.

I you're on to something, good info.