Fork question

[farmer58za]

Another question:
The forks on my '75 400 give a "clunk" when topping out. Is this normal? They are the Ceriani with the stiffening rib. I'm running 185cc of 10 wt fork oil per leg

thanks
David

Regards

David ('75 KTM GS400)

[Rocket]

David
Take your forks apart and you should have a little short spring that goes over the dampning rod that is approximately one long, that may be broke or missing.  This is the top out spring.  I believe the correct oil amount for the 35mm Ceriani's is 200cc.  What weight fork oil are you running?  The forks with a rib also have valving in the slider tube that may need cleaning.
Rocket

[Mike OReilly]

Checking for the top out spring is definitely a good idea.
I ran those forks for AHRMA motocross very successfuly, using 190cc of 25 wt. oil (mixed 30 wt. with 20 wt.). 10 wt. seems a bit light; I'm not surprised that it would produce a "clunk" on top out.  Experiment with combinations of 20 wt. and 30 wt. and I would expect that it would solve the problem. These days, the only place on this side of the pond that you find 30 wt. is at Harley shops!
Good luck.
Mike

[imported_n/a]

Guys,

I'm starting to rebuild a set of these forks and have hit a snag.  Before I put too much torque to it, I thought I would ask the question.

I've removed the bottom screw so I can disassemble one of the legs.  It won't come apart.  Do certain things have to be in alignment or is something just stuck?  I've rebuilt the 32mm and two sets of 7" travel 35mm, and have not had this problem.

Glenn

[Kip Kern]

Just a guess, but if the leg is compressed, you have removed the damper rod bolt and the leg won't pull out, you may have a bent leg that is "jammed" in place.  I would place the lower leg in a vice (protected of course) place a strap wrench on the upper leg and twist and pull, not twist and shout[]

[OUCWBOY]

Kip,
Sometimes you may just have to "Twist and Shout" while you twist and pull!:D

Donny Smith

[imported_n/a]

Kip, I can pull until the top out spring compresses, and I've tried jerking a little, and it just hits the spring, just like it's still screwed together tightly.

Glenn

[Kip Kern]

Glenn  If you have the damper rod bolt out and still can't pull it apart that is one I have never experienced.  You may need to consider the knowledge of an even greater wizard out in POG land, I am stumped[8]

[Doug Wilford]

Questions first:    Are you able to twist the fork tube in the leg? Refer to bent tube!    Are you able to Move the tube up and down?   Sometimes the inner tube which the bolt threads into, is froze internally from rust or dirt.  Are you able to remove the spring and the inner tube?   If all is failing, clam the tube in the protected jaws of a vise, remove the dust shield, get a wooden, (hard wooden) block and proceed to knock the damn bottom end off the tube.   Always have fun though.

[firstturn]

Kip,
  I don't know about wizard[] but here is what I have experienced.  I think you are saying that you have the bottom allen head bolt (should have a copper washer) out that holds the damping rod assy.  If this correct??  If so what I had to do(don't let Kip read this) is use my extra long 3/8 extention and insert the round end into the bottom of the leg(to keep from damaging it).  Put the leg into a vice (protected) and use the hammer gently to tap it out.  After it comes out (or I hope it does) you will probably find that it doesn't slide back in to easy.  I used a brake hone with a homemade extention to go down inside the fork leg and cleaned out the build up and what ever else grows inside there.  I always clean up the sliders (guides) with soft steel wool.
  If I'm wrong[B)] about this please don't embarras me in front of Kip and Donny.



Ron Carbaugh

[firstturn]

See Kip I told you I think we should ask Doug what he thinks.

Ron Carbaugh

[Rain Man]

is it possible for the bottom of the fork tube to "mushroom out" from years of use? that would not allow the tube to clear the bush. Just a thought
Raymond

[imported_n/a]

Thanks to all for a plethera of suggestions.  I will print them and head out into the garage this weekend.

Yes, the stanchion is straight, the slider is straight, because the fork will travel its full (8") length without binding.  I can twist them okay.  The spring comes out just fine, it just won't come apart.

I'll let you know how it goes on Monday.

Glenn

[Speedy]

quote:Originally posted by Glenn Sonntag

Thanks to all for a plethera of suggestions.  I will print them and head out into the garage this weekend.

Yes, the stanchion is straight, the slider is straight, because the fork will travel its full (8") length without binding.  I can twist them okay.  The spring comes out just fine, it just won't come apart.

I'll let you know how it goes on Monday.

Glenn

On some hot days in Italy at the CERIANY plant,the workers put little GREMLINs inside the forks.They hold onto the inner tube to make you sweat.Spray some insectisice into the fork.That kills the GREMLINs and they let go.(Here in Canada we call that DIESEL OIL.)
Cheers,Speedy------>>>>>>>>>

Helmut Clasen KTM
162 Hillcrest Ave
L9H 4Y3
Dundas Ontario Canada
Ph.905-627-5349
[email protected]
http://speedy_c.tripod.com
Sachs GP-GS 250-7A reeds
Zuendapp 125 GS ISDT repl.73
KTM 450 EXC Auto.03
Duke spec.Edit,1996
Adventurer 02

[Rain Man]

okay Glenn, Monday has come and gone, the curiosity levels stifling, whats the final results?
Raymond