Inner bushing on Fork lowers

[wherearewe]

Hey guys. Anyone out there ever replaced the inner bushing on a fork lower (the teflon coated one)? Got a nicely polished lower that has a bushing where the teflon looks a bit worn. There has to be a better way than shopping around for an entire replacement lower and discarding an otherwise good part - I've done that before.

Some research says this might work, but I can't find much confirmation outside a couple of posts here and there...

http://sideburnmag.blogspot.co.nz/2013/06/mystery-part.html?m=1

cheers

 

[peterg]

Have you looked at boats.net

 

[jetmechmarty]

I don't think that part was ever part of the breakdown.

 

[wherearewe]

Jetmechmarty is right. The bushing was never listed as an individual part and factory pressed in. Maybe Yamaha thought it would last the life of the vehicle. Later vehicles have is similar inner bushings listed, the fork slide bearing. It just seems half arsed to rebuild forks with all new tubes, seals, upgraded internals and then leave a worn out part.
I think I'm going to try this SR500 route. Ill go today to Yamaha and see what can be done, and maybe do a test on an old lower. Either way since no one else seems to have explored this, ill report back with any findings.

 

[650Skull]

http://www.xs650.com/threads/fork-bush-removal.43459/

 

[wherearewe]

http://www.xs650.com/threads/fork-bush-removal.43459/

Seen that thread. Ironically I told him to just find another lower. That part number is the same one I found. Chances are he found the same blog post I did. Thing is he never came back to report that it was a successful replacement and the part number was correct. All we know is Razor cut the old bushing out....

 

[650Skull]

It was the only thread i knew off relating to that bush with a part no. Didn't realize you had kept track of the thread.

 

[wherearewe]

It was the only thread i knew off relating to that bush with a part no. Didn't realize you had kept track of the thread.

I would send him a message and ask how it turned out but he doesn't seem active.

 

[TwoManyXS1Bs]

And another one:

http://www.xs650.com/threads/front-fork-bushes-tricks-wanted.39293/

 

[wherearewe]

Ordered a bushing through Yamaha. $10 approx ex Japan. They refer to them as metal slides. Will take a couple of weeks but will report back if successful.

 

[wherearewe]

For those interested I can confirm these bushings fit on 35mm forks. The ones I removed are stamped DU9K and the new ones are marked DK57A, the only difference being the newer ones are 0.05mm taller.

Here's the removed bushing. I basically made 2 cuts, alternating from one to the other. One I made on top of the split. I used a diamond point rectangular Dremel bit as pictured. The flat end and long grinding area made it perfect for control, much easier than a ball type. I just took my time & using a small flat screw driver I would gently tap behind the bushing between the 2 cuts to see if it was going to bend inwards (emphasis on gentle otherwise you could damage the seat). Once it got started I would just grind a little more, tap again, grind, and eventually it was ready to be hit with a heavy punch. Then it came straight out without marking the seat at all.

 

[mrtwowheel]

Have to ask the question......How did you determine that the bushings needed to be replaced?

Scott

 

[wherearewe]

Have to ask the question......How did you determine that the bushings needed to be replaced?

Scott

Good question. I dont claim to be a suspension expert by any stretch of the imagination, so don't take what I'm saying for gospel. My determination was based on how they looked. At least 50% of the teflon had worn away from use. Some searching online suggested the wear limit specified by other manufactures of the time was about 2/3 worn, but in other places I found people saying if you can see any wear replace them so I dunno.
I guess I didn't see the point of putting in all new fork tubes and seals over the top of bushings that looked spent, especially since getting the seals out can be a pain in the arse. Honestly it wasn't that difficult in hindsight. I might also add that the new bushings are much improved in terms of stiction over 40 year old ones...