TT250 Adjustable Fork Cap Rebuild

[2LZ]

Hi gang. As some of us have received some fork caps that weep around the dampening adjuster screw, I thought I'd tackle that today. I believe this may be the same fork cap for the new RX3 so I'm sure if not identical, dang close.

Pic 1 - You'll see that it's probably going to take a heat gun to get these pieces apart due to the red loctite-like thread lock they used. Thanks for the heat gun idea Weldangrind....though flame still would have been more fun. ;-)

Pic 2 - You'll see that they weren't kidding. The thread lock ran the entire threaded area all the way down on this one.

Pic 3 - Once extracted, this is what it looks like inside. Note the blade connector the rod mated with....and the mystery gunk. At first I thought it was ground up o-ring....but the o-ring ended up being intact so, mystery gunk it is.

Pic 4 - Once you pop out the screw/blade to access the o-ring, there will be a very small spring and ball to come with it. Be careful. Note the hole where it all lives.

Pic 5 - You'll see six detentes that the ball is supposed to "click" to maybe keep it in place and for measuring adjusting, I guess. "I'm out three clicks man!"

Pic 6 - You'll see that I've found a replacement o-ring in my stock and put some good grease on it for seating and installation. Note that the cap has been completely cleaned of any mystery gunk for a good, clean seat. Also, my adjuster screw looked like it was adjusted by the same ham-fisted mutant that drilled our license plate frames. I had to hit the head of the screw lightly on my wire wheel to remove the burring that had occurred since someone had a seizure on it with a screwdriver. I didn't want the new o-ring to get buggered up rolling over it on its way to its new home.

Pic 7 - Now it's getting tricky. You have to get the spring and ball back into position. Put the spring in it's hole and push the piece just into the cap hole far enough to let the spring rest on the inner surface. Then, drop in the ball and let it run around the outside of the screw piece. Take a small pick and push the spring into the hole, allowing the little ball run in front of and be held in place by the spring.

Pic 8 - Use a small flat blade screwdriver to shove the little ball into the hole. When it goes in, push the screw adjuster and o-ring into it's new seat. Then, screw the other half of the cap together using a thread locker. I prefer blue locktite as I'd like to get it off someday without a heat gun or torch. Just my preference.

Pic 9 - The finished product for back stock, ready for duty.

Regarding the ball and spring, it's up to you if you want to reinstall. I did for the thread, but the o-ring holds the screw in place pretty well. I'm sure if you're passing Roger DeCoster over a triple jump in the "retired class", you may notice a slight bit of dampening imbalance if the screw moves a little but...up to you.

[2LZ]

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[BlackBike]

You make the most boring things entertaining with your remarks

So you attribute the leakage to the black o ring . how does something like that leak in such a small cavity ? I guess once a microscopic fissure occurs on a seal, thats a pathway for high pressure fluid leak. Amazing.

What can go wrong, can and will go wrong.

[2LZ]

Originally Posted by BlackBike

You make the most boring things entertaining with your remarks

So you attribute the leakage to the black o ring . how does something like that leak in such a small cavity ? I guess once a microscopic fissure occurs on a seal, thats a pathway for high pressure fluid leak. Amazing.

What can go wrong, can and will go wrong.

Thanks! This one was more for the archives. Someone down the road will ask....

All o-rings need is a small slit or flat spot or a small chew mark to fail. Lets not forget that when my fat a$$ sits on the forks and bounces up and down, those little rings are holding back hydraulic pressure being forced at them by a dampening tube trying to stop the bounce.

[BlackBike]

Originally Posted by 2LZ

Thanks! This one was more for the archives. Someone down the road will ask....

All o-rings need is a small slit or flat spot or a small chew mark to fail. Lets not forget that when my fat a$$ sits on the forks and bounces up and down, those little rings are holding back hydraulic pressure being forced at them by a dampening tube trying to stop the bounce.

That must be a Hugeforce.