I've never had so much grief with a fork seal before. Having changed plenty of USD and conventional fork seals over the years, all with no issues, the Gixer's forks are doing my head in. Plenty of you suffer with leaking fork seals on GSXR's so this time I'm determined to work out why. This bike's done a few k's, and had a bit of stick, but you can seal up the forks of an old 'crosser with epoxy in the rust pits and a bit of wet & dry so lets see if we can't fix this thing on the cheap.
I've heard bushing is a weak point on the 43mm Kayaba's so I'll double check them to make sure they haven't worn through the Teflon coating. Bushes are actually available through the better suspension specialists, but they're a press fit, requiring some form of puller to remove them. If I can get away with it, I will. I have slight scratches in my stanchions so that doesn't help, and I've also never fitted seals the recommended way - with a seal driver! It could all be my fault (and probably is).
Ok, this time I'm going in fully prepared. I've bought a Motion Pro seal driver so the seals can be installed on the stanchions before assembly (this could be where it's all going wrong), and I'm going to try fine (1000) wet&dry on the chips/scratches. Different people say different things. I've been advised against using anything abrasive on the DLC coating because it's so thin but, if they're damaged, it's means renewal is necessary anyway. I'll take the advice of a Suzuki tech. who said to crosshatch the stanchions with a kitchen scourer. Nothing much to lose in fairness.
Thanks to K-tech suspension I have the correct NOK fork and dust seals. Can't recommend these guys enough. Answered my emails with helpful advice regarding the bushes, and sent the seals out very quickly.
The culprit! A chip on the inside of the left stanchion. With no viable option, other than new stanchions, I used 1000 grit wet & dry to smooth it out. It won't show on the inside and shouldn't now cause any damage to the seal. A good look into the fork outers and the bushes seem good - smooth, not worn through and very little play between tube and stanchion. Cool.
Quality seals, they certainly feel different to the aftermarket crap!
Seal saver - wrap the top with insulation tape to prevent damage when fitting, and smear fork oil down the stanchion.
Remember, dust seal first, then the fork seal and finally the washer. The circlip can go on afterwards. I used red rubber grease on the seals initially, but that proved to be too sticky so I added fork oil to the stanchion and seals too. Worked a treat.
One Motion Pro seal driver (showing it fitted). To push the seal in I placed the outer tube upside down on the floor and pushed the seal down into place.
If the seal's fitted correctly, the circlip should spring out and into its groove easily.
Back in and here's hoping we get more than one ride without springing (get it?) a leak! Went to 109mm air gap this time instead of the 101mm recommended by Suzuki, and used 5W hydraulic oil (Valvoline ISO15).
New rubber too! Dunlop Q3's sent over from Rocky ATV - another class act. Tyres arrived in Australia within a week, and the prices were exceptional too.
Yum, love new tyres!
Brilliant, sublime, hard, but not harsh - this Gixer's back to its best and ready for a day at the Queensland Raceway, and no leaks either... yet.