Fork Seals - AK20 forks

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

RossKean

Well-known member
Joined
Feb 15, 2010
Messages
6,778
Reaction score
3,307
Location
Fredericton, NB
I have a leak in my left fork.  Bike has Traxxion setup with AK20 fork cartridges. 

I will certainly start with trying a Sealmate but if that doesn't fix it, has anyone done seals and bushings on this configuration?  I know Traxxion does not use the middle bushing. 

Any other differences compared to a "standard" seal/bushing replacement?  

Recommended fork oil for this?  I have used Bel-Ray 5W in the past for my '07.  I think Traxxion recommends Maxima 125/150 (7 Wt).  A little more viscous than the Bel-Ray according to the chart in this link:  https://www.peterverdone.com/archive/lowspeed.htm

Special tools?

Does the "slide hammer" method work well to separate forks?  (Thinking it could be easier without the middle bushing to jam under the top one.)

Hope to avoid the full meal deal this time but will likely need it eventually.  Bought the bike used but probably 65,000 miles on these forks.  I will do fork oil this year,  even if I don't have to do seals.(I have FJRed"s excellent post on fork seal/bushing replacement)

https://www.fjr-tips.org/maint/ForkSeal-BushingReplacement.pdf
 
The Seal-Mate seems to have done the trick.  At least for now.  Still interested to hear from anybody who has replaced seals and bushings on Gen II forks with Traxxion AK-20 innards and just the two bushings.

 
had a leaking seal not cured by using Sealmate this go around and found a very fine vertical scratch barely detected by bright light and fingernail feel. I buffed out with 800-1200 wet/dry paper which cured the weep. It was amazing how much oil passed by this fine scratch. How it got there, I will never know....

Good idea to check your seals monthly as you do not want to contaminate your calipers/pads. I tied a small bit of rag on the brake line to catch a drip while figuring how stop the drip.

 
Good idea to check your seals monthly as you do not want to contaminate your calipers/pads.
Yeah, I know!  Got the forks sorted out (for now) but front brakes required a little more force to stop effectively until the oil got burned off.

I don't think it really damages the (sintered) pads but it does take a little while to get them working right.  If I hadn't been lazy, I should have removed the pads, cleaned the rotors with varsol, wiped the pads with a varsol-soaked rag and then ground off the surface of the pads with a little coarse sandpaper.

A few hard stops seems to have accomplished the same thing.

 
just be careful of solvents on caliper seals. I would use IPA alcohol instead. Good idea to take some time to pull the calipers, remove the pads and get a Q-tip and clean all the fork oil around them. Probably the most important item on your machine for safety in my opinion.

 
just be careful of solvents on caliper seals
Didn't say anything about varsol on caliper seals.  Rotors and brake pads only and applied with a rag.  Varsol isn't especially aggressive toward rubber and is a far better solvent for oil than IPA.  (And far less aggressive than brake cleaner!!) Calipers typically get cleaned with an alkaline degreasing detergent (Spray Nine in Canada), scrubbed with my wife's toothbrush and thoroughly rinsed.  When pads are changed, pistons get extended as far as I dare and dirt is wiped off pistons and seals with a dry cloth before pushing them back.  Didn't do a thorough disassembly and cleaning this time - pads likely need to be changed this year (or at least rotated).   

 
Since this was first posted, I have had a second leak in the left fork and a leak in the right fork.  I was able to restore these with the Sealmate but am pretty sure I will have to replace them - probably over the winter or early spring.  Haven't been riding on especially dusty roads - looks like the seals are just getting worn.  No visible scratches on the fork tubes.

1) Anybody have experience with doing seals/bushings with an AK-20 setup?  Specifically, what tool (if any) is required to hold the cartridge while the lower bolt is removed?  At least I don't have the middle bushing to contend with. 

2) What did you use for oil level and did you use the Maxima 125/150 recommended by Traxxion?

3) Any difficulty getting it back together and adjusted?

4) Anybody use a bellows type gaiter to keep dust out of the fork seals?  I might give that a try this time.

Thanks

Edit:  I wrote to Dan at Traxxion and this was his response about the cartridge holding tool...

"Instead of having a $200 cartridge holding tool like other brands, we made the inside of the upper bearing housing a square. We use a piece of square tubing with a hole drilled in the end, stick a screw drive through the hole as a handle. We include it free with AK20s. It’s 5/8” square tubing, you should be able to find that locally."

 
Since this was first posted, I have had a second leak in the left fork and a leak in the right fork.  I was able to restore these with the Sealmate but am pretty sure I will have to replace them - probably over the winter or early spring.  Haven't been riding on especially dusty roads - looks like the seals are just getting worn.  No visible scratches on the fork tubes.

1) Anybody have experience with doing seals/bushings with an AK-20 setup?  Specifically, what tool (if any) is required to hold the cartridge while the lower bolt is removed?  At least I don't have the middle bushing to contend with. 

2) What did you use for oil level and did you use the Maxima 125/150 recommended by Traxxion?

3) Any difficulty getting it back together and adjusted?

4) Anybody use a bellows type gaiter to keep dust out of the fork seals?  I might give that a try this time.

Thanks

Edit:  I wrote to Dan at Traxxion and this was his response about the cartridge holding tool...

"Instead of having a $200 cartridge holding tool like other brands, we made the inside of the upper bearing housing a square. We use a piece of square tubing with a hole drilled in the end, stick a screw drive through the hole as a handle. We include it free with AK20s. It’s 5/8” square tubing, you should be able to find that locally."


I was going to post up you need the 5/8 square tubing.  But Dan already let you know that.  Other than that you need standard tools, seal driver and torque wrench.  Heat does help in the removal of the bushings.  OEM Yamaha seals and bushings recommended.  Pay attention to the oil level that Traxxion recommends.  Other than it is the same as if they were stock fork cartridges.

 
You could contact Dan at Traxxion and I am sure they would sell you one that they send with their kits.
Quite likely, but shipping cross border and dealing with customs is a pain in the ass and expensive.  Will look locally thoroughly before I go that route.  There is a pretty good chance that I would not require it but...

Nevermind!  When I bought my 2011 a couple of years ago, the original owner included a bunch of "stuff" including a cardboard box the Traxxion springs came in.  (The OEM springs were in that box and I had assumed that was all.)  On a whim, I just had a look and the 5/8" square steel tubing that came with the Traxxion kit was also in that box!

I should be good to go once I get the bushings, seals and other bits.

 
I was going to post up you need the 5/8 square tubing. But Dan already let you know that. Other than that you need standard tools, seal driver and torque wrench. Heat does help in the removal of the bushings. OEM Yamaha seals and bushings recommended. Pay attention to the oil level that Traxxion recommends. Other than it is the same as if they were stock fork cartridges.
I need to replace the fork oil in my forks fitted with the AK20 kit. The only reference I can find for the oil level height Traxxion recommends is 160mm from the top (spring, cartridge, etc. removed). Just wanted to confirm this oil level with any one running the AK20 kit.
 
I need to replace the fork oil in my forks fitted with the AK20 kit. The only reference I can find for the oil level height Traxxion recommends is 160mm from the top (spring, cartridge, etc. removed). Just wanted to confirm this oil level with any one running the AK20 kit.
Hi James - haven't seen you around in a while! Still in Australia?
I did my AK-20 a couple of years ago and this is the information that was originally supplied with the forks. Seems to me I just copied these settings.
I have the full set of Traxxion Dynamics instructions including Specific Instructions for FJR. If you need a copy, PM me with your email address and I can send them. (I would scan and PDF what I have since they are not electronic format.)
I did installation without the middle bushing (2011 FJR)

I also have the following from an email from Traxxion - note fork oil recommendation:

"Baseline settings for the forks would be 3 spaces showing preload, 16 clicks out on compression, and 24 clicks out on rebound. Turn the compression adjuster in and count the clicks, so you know where it currently at, further out = softer.

I have attached instructions for service the forks with AK20s, very similar to your OEM cartridge fork. Use OEM seals and bushings. Use Maxima 125/150 oil, oil level is 160mm."

1696858954193.png
 
Thanks for the detailed reply Ross, much appreciated.
Since moving to Oz, I've been spending most of my riding time doing Adventure riding, so the poor FJR has been less active here. I've only got about 320,000 miles on her at this time.
Have PMed you my email address, so please forward any relevant docs you have, thank you.
 
Top