Question about Forks and Seals

[thisisbenji]

So I'm in the process of doing the R6 fork mod to my bike. I ordered two separate fork legs off of eBay. One was new old stock and the other was a used unit.

When I flip the used fork leg upside down and then right side up I can hear the oil going from one end to the other. When I do the same thing with the NOS fork leg I can hear the oil but it's very faint

If I hold the NOS fork upside down when I flip it back it seems to take at the most 1 second for the oil to stop moving. With the used fork it takes closer to 5 seconds.

Help!

 

[ozgurakman]

simple, probably used forks' oil is changed with heavier fork oil.
I recommend change both of them and if needed, change seals of used fork.
If no leakage and no cracks on seals, don't waste your money IMO.
Thanks button is at the below of this text, if you liked my guess.

 

[FinalImpact]

Change the oil and observe the depth of the CAP to the damper rod. The nut must be 11MM on the dot or you risk damage to the damper assembly when using the rebound adjuster (Screw at the top).

As for the sounds; storage flat vs upright could cause separation and as pointed out, different forks with different oils (i.e. not of the same origin) could flow and sound different with different weights of oil.

Freshen the oil to the same make and grade and follow the FSM for proper set up. You will be rewarded with MUCH PREDICTABILITY over the stock setup!

Good Choice! :thumbup:

 

[thisisbenji]

So it sounds like I should bring both forks into my local shop for service before I install them? You mention the nut must be 11mm, will the shop know about that?

 

[FinalImpact]

If you pulled the nose apart, you can change the oil. Take the cap loose and with a 17mm and 14mm, pop the cap off and dump the oil. On the used one dump some spare clean fluid in and cycle the the damper up and down. Repeat a couple times till it comes out clean.
5 or 7.5wt max.

The basic info is here. Take a look - 2nd post.
08 FZ6 Condensed Build thread ~Final Impact~

OK i don't see the fill depth and im not at a location w acc to R6 pdf but each leg takes a whole pint. Going over is ok. Better than being too low. Just make them the same.

Also, because one is used and the other new, lean against a wall and put your entire body weight on the assembled fork. With Ziptie around the tube take three measurements of how far each leg compresses to sorta verify the spring rates are near the same. You'll need to pad the top with a rag and dont bounce, just push get yer feet off the ground. Think of it as a poor mans spring test!
Maybe record it for later. PM me if need r6 f s m or do search. Its on another forum.

 

[FinalImpact]

In the link above, follow the link in the 1st post to this... See "R6 Fork, Best Investment EVER!" 2nd post and it has all the technical info you need. Fill levels etc.

PS when filling and getting the air out, measure level with springs out, don't pump the damper more than 4" or it may suck air and give you a false high.
Have fun... Its pretty straight forward.