Fork Rebuild, need some input

[Patmac6075]

Finished front end rebuild, tires, bearings, complete brakes, complete forks, springs, sliders, and seals. WHAT A DIFFERENCES!

I used 10wt fork oil and I seem to get a noticeable "pogoing" action at lower speeds (under 35)...it's quite irritating, especially around 25mph, at highway speeds I am rock-solid.

I'd read many times that 10wt is the way to go.....has anyone else had this issue?

BTW - Progressive springs, 360ml of oil (per recommendation), and no air assist. Although pogoing still persists no matter how much pressure is in forks.

Question is.....heavier weight oil?

[bongobobny]

Hmmmm, sounds like everything I did to MY '84! I used forks from a late model MK2 with the little springs at the bottom along with the regular springs. Unfortunately due to the electrical fire in the wiring harness in '09 didn't have a chance to ride it much at all.

 

A looooong time ago, possibly even before the great crash of '06 there was a member from Toronto that did an intensive study with different weights and volume. From what I remember the more the oil the stiffer the suspension. I think he tried with all the way into the low 400's for volume. Also, as expected, the heavier (thicker) the oil, the stiffer as well. I think he tried from 5 to 20...

 

I guess the only way for you to find out is experiment!

[Patmac6075]

I followed (from memory) this thread, http://www.venturerider.org/forum/showthread.php?86243-Front-forks-what-you-should-know-progressive , but after rereading it, Jason also experienced pogoing with 10wt and made his own "voodoo" 12wt which apparently fixed his problem....maybe I'll give that a try.

[Flyinfool]

I have read a few posts of using 12.5wt oil as the magic bullet. When I do my springs I plan to mix a quart of 15 and 10 together to get the 12.5. I am also planning to install the anti dive block off plates.

 

While you were doing all of this did you also do the steering head bearings? I just decided that I need to add them to my list.

[Patmac6075]

Wish I would have and certainly should have, but I didn't replace the steering bearing....mine move without notchieness and no noticeable play, but I agree....with their age...it is the right thing to do.

[MiCarl]

More oil reduces the air volume on top which increases the spring rate. The volume (so long is there is the bare minimum) won't affect pogoing.

 

The pogoing is because the damping rate is too low. A higher oil weight is the way to go.