Grease Fork Seals?

[Denver_FJR]

Won the lottery and discovered both fork seals sprung a leak this spring. Have forks apart and about to reassemble but I see mixed responses (not here) about whether to use an assembly lube/grease on front seals or just coat with fork oil.

Thoughts?

 

[Donal]

According to the 'blurb' good quality fork oil is supposed to include additives that help keep the seals in good condition e.g. "while seal conditioners are added to keep seals soft and pliable"YMMV

 

[eddie]

Coat with fork oil only

 

[Denver_FJR]

I'll add that my '07 currently has 30k miles. The first set went out around 15k miles and I used the opportunity to send both forks to GP Suspension for seals and valve upgrade. It does appear there was some type of grease between the seal lips this time, but seeing they again failed at 15k interval is making me think it doesn't matter. I also picked up a 2012 Tenere and it's seals were shot at 18k. I think I'm seeing a trend here with Yamaha seals.

 

[Viper Pilot]

I'm really surprised your fork oil seals are failing! Have you tried to clean the seal to tube interface with a "Seal Mate" tool? Are your fork tubes scratched ? I don't think it's normal for the seals to "fail" like that. Just my experience..............

 

[RaYzerman19]

Agree..... if they are getting dirty, they may leak and need to be cleaned out. But also look for pitting in your fork tubes that might be wearing away at seals and address that or it will continue.

 

[HyperPete]

Were they aftermarket seals? Over on the VMax forum I frequent, it's commonly "known" that the aftermarket seals are not worth installing, that they fail early. They always suggest using Yamaha seals.

 

[Denver_FJR]

I'm really surprised your fork oil seals are failing! Have you tried to clean the seal to tube interface with a "Seal Mate" tool? Are your fork tubes scratched ? I don't think it's normal for the seals to "fail" like that. Just my experience..............

I attempted the Seal Mate trick on the FJR at 15k and on the Tenere without success. Since both seals were leaking I didn't even attempt it this time. Talking with the mechanics at my local dealership, they mentioned seeing seals fail, typically around 12k to 20k miles but noting a few exceptions on the high and low ranges. Anecdotally noting folks who ride year round will go through seals a bit quicker.

Tubes are in great shape as were the bushings. The bushings surprised me considering I've seen a number or reports about worn bushing with under 25k.

 

[RossKean]

FWIW - I have changed fork seals on my '07 two times. Each time, I got somewhere around 70,000 miles out of them. Both times, I tried a Sealmate and it gave me a temporary reprieve but only lasted a couple thousand miles.

 

[Denver_FJR]

Were they aftermarket seals? Over on the VMax forum I frequent, it's commonly "known" that the aftermarket seals are not worth installing, that they fail early. They always suggest using Yamaha seals.

Not sure if seals were OEM since they were installed by GP Suspension. My local mechanics also mention OEM seals are the way to go and that's what I'm replacing with.

Considering the hassle and cost of pulling forks, I've been meticulous about keeping fork tubes clean, at least when bike gets washed. I usually give them a shot of silicon lube to keep them slick and repel bugs and crud.

I could find no sediment between dust seal and seal, so while possible it would surprise me if a few grains of sands/bug guts made it past dust seal and wedged open seal.

I'm currently leaning to just lubing with fork oil and installing.

 

[Fred W]

I generally put a very thin layer of grease only on the outer circumference of the seal, just so it can easily be pressed and seated in the lower fork leg. I do not lube the lips of the seals at all. The inner fork leg should be scrupulously cleaned with no nicks or pits in the surface. Just be careful when you work the lip of the seal over the top of the inner fork tube so you do not damage the lip.

The underside of the seal will be exposed to fork oil splash from below. The upper edge of the seal will be dry for it's entire life. Unless you have done something and damaged the seal they should last for many miles. Well more than 20 or 30 k miles. A seal that is leaking that soon is just dirty.

If you can get all the dirt out from under the seal with a seal mate it will reseal for as long as you manage to keep the fork legs clean. Those folks that brag about never washing their bikes are probably also the ones replacing their fork seals prematurely.

 

[Denver_FJR]

I generally put a very thin layer of grease only on the outer circumference of the seal, just so it can easily be pressed and seated in the lower fork leg. I do not lube the lips of the seals at all. The inner fork leg should be scrupulously cleaned with no nicks or pits in the surface. Just be careful when you work the lip of the seal over the top of the inner fork tube so you do not damage the lip.

Thanks, this is going to be my plan as well.

The underside of the seal will be exposed to fork oil splash from below. The upper edge of the seal will be dry for it's entire life. Unless you have done something and damaged the seal they should last for many miles. Well more than 20 or 30 k miles. A seal that is leaking that soon is just dirty.

If you can get all the dirt out from under the seal with a seal mate it will reseal for as long as you manage to keep the fork legs clean. Those folks that brag about never washing their bikes are probably also the ones replacing their fork seals prematurely.

I want to believe in 30k seals! But I have had poor success using the Seal Mate trick, and there's lots of reports similar to RossKean where it only provided a short fix.

 

[RossKean]

I want to believe in 30k seals! But I have had poor success using the Seal Mate trick, and there's lots of reports similar to RossKean where it only provided a short fix.

The Sealmate gave me a short term fix but that was on seals that had already gone 70,000 miles. At that point, I expect they were significantly worn. In any case, the bushings were in need of a change and did the whole thing at once. I change fork oil maybe every 30-40 thousand miles.

 

[RaYzerman19]

I usually lube the inner and outer seal with fork oil, to help the seal seat and to prevent stiction (for as long as that oil might last between the two lips). I wouldn't use grease on the inner lips, but on the OD is OK. I don't lube the dust seal at all.

We've taken apart many forks at tech days (Gen 1 & 2), and the trend seems to be lower bushing wear is showing itself fairly well at 30k......... I see no reason why seals won't last that long, most have exceeded that from what we've seen, some much longer. So, a 30k interval to change up bushings and seals might seem a reasonable expectation.......

 

[El Toro Joe]

...

never mind

 

[Fred W]

Agreed, if you are popping the seals out to replace worn out bushings on a second Gen at ~30k miles, you may as well stuff a new seal in there on reassembly. You've already done all the work.

OTOH, I've done refurb on several 1st Gen bike forks at double the mileage (50 - 75k miles) and the bushings on them were all fine with the teflon coating still intact. I credit that to the fact that 1st Gens have just two bushings. But by 75k miles the lips of the seals were slightly worn and squared off where they rub against the inner tubes.

If you are unable to get a relatively young oil seal to reseal, or even moreso if the fix doesn't last, it's probable that you just didn't get all the dirt out from under the double lip of the seal, or you didn't clean the fork leg well enough. You really have to dig that seal mate in all the way past the second lip to get all the spooge out, and it often takes a few attempts. I found it much easier to do with the fork leg removed from the bike.

 

[HyperPete]

I usually give them a shot of silicon lube to keep them slick and repel bugs and crud.

Hmmmm, I wonder if the silicone spray might be contributing to the seals breaking down. (Just grasping at straws...)

All I do is keep 'em clean, and when I am waxing my bike, apply a coat of wax to the fork tubes too.

 

[Fred W]

Wax, or any other layered application, is probably a bad idea. The lip of the seal would (eventually) scrape through the wax layer and then build up on the lip of the seal. What you want is the perfectly clean seal lip sliding on the perfectly clean and smoothly polished surface of the inner fork tube.

On my 1st Gen I was having to clean the seals pretty often. I decided to ditch the small fork protector and install the NOJ brand neoprene gaiters, which cover about 3-4 inches up the inner fork tube. This reduced the frequency I needed to clean the fork seals with the seal-mate considerably.

Keep 'em clean!

 

[Denver_FJR]

Ha! Finally perused the fork assembly section of the FSM and it does call for lubricating seal lips with lithium-soap based grease.