Fork seals?

[roy]

Anyone here have residual oil film on both fork tubes. Only 250 miles and both have exhibited this since day one. I wipe it off and one ride I have the film rings on both tubes. From last experience in racing and doing trackdays which is very hard on forks this symptom will not cure it self. I had read about a few S10's doing this and was hoping mine would not. Fork work locally is not the way I wanted to get started with my first yamaha. I plan on giving it some more time before pulling the panic bar. Who makes the suspension for this bike? Kayaba or Showa ?

 

[roy]

I am 525 miles, rolled 300 today. Both forks are still showing oil rings on the slider tubes. Does not seem to be getting any worse or better. I plan to take it by the dealer next week. Weird how both sides are doing the same thing.

 

[~TABASCO~]

Hummmmmm... normally I would say that might be bad... but I would put a few thousand on them and then keep an eye on them... Its under warranty. Can ya post a picture?

 

[roy]

Okay I may have discovered the problem. After owning and riding dirbikes for years sunday morning a light bulb went off in my head. One of those early morning type thoughts you either have in the shower or at the breakfast table. Anyway I said I wonder if the front wheel is on right, forks centered that type thing. So I look in the service manual for the axle torque spec's and pinch bolt spec. I loosened both pinch bolts, went to undo the axle and it was way over tight, suppose to only be 52 ft. lbs it was maybe 75. So I re-torqued it correctly and then I did the trick, lightly bumped the front wheel against the wall not using the front brake or anything like that. Just a bump with slight fork compression. This will center the axle on the fork bottoms. Then I torqued the pinch bolts in their prescribed method. Yamaha uses a weird 1-2-1 approach on this. Clearly states it in the sevice manual. Rode it 106 miles sunday and 46 miles to work on monday. What was leaking front forks on both sides is now only a sheen film left which may clear on a few more rides due to residual oil being there for 600 miles. So the moral of this story is center the forks on this thing or those low stitcion seals will weep. Seen this happen on many dirtbike swith inverted forks. Verdict is still out as to whether they will stop completely but it is 75% better than it was before I worked on it.

 

[colorider]

Okay I may have discovered the problem. After owning and riding dirbikes for years sunday morning a light bulb went off in my head. One of those early morning type thoughts you either have in the shower or at the breakfast table. Anyway I said I wonder if the front wheel is on right, forks centered that type thing. So I look in the service manual for the axle torque spec's and pinch bolt spec. I loosened both pinch bolts, went to undo the axle and it was way over tight, suppose to only be 52 ft. lbs it was maybe 75. So I re-torqued it correctly and then I did the trick, lightly bumped the front wheel against the wall not using the front brake or anything like that. Just a bump with slight fork compression. This will center the axle on the fork bottoms. Then I torqued the pinch bolts in their prescribed method. Yamaha uses a weird 1-2-1 approach on this. Clearly states it in the sevice manual. Rode it 106 miles sunday and 46 miles to work on monday. What was leaking front forks on both sides is now only a sheen film left which may clear on a few more rides due to residual oil being there for 600 miles. So the moral of this story is center the forks on this thing or those low stitcion seals will weep. Seen this happen on many dirtbike swith inverted forks. Verdict is still out as to whether they will stop completely but it is 75% better than it was before I worked on it.

GREAT info!!!!

Thanks for posting Roy!!!

 

[fredz43]

The Yamaha setup instructions for this bike address this and also specify those proper torque levels.

 

[roy]

The Yamaha setup instructions for this bike address this and also specify those proper torque levels.

I am sure they do but evidently they were not used on my bike during assembly even with a yamaha parts/service rep there supervising the job. The old saying goes "if you want it done right then do it yourself" I am a firm believer in that statement. I have wrenched on bikes for years, road race bikes, dirtbikes and plenty of my own streetbikes. Worst experiences for me always go back to the initial setup at purchase time.

 

[Koinz]

Okay I may have discovered the problem. After owning and riding dirbikes for years sunday morning a light bulb went off in my head. One of those early morning type thoughts you either have in the shower or at the breakfast table. Anyway I said I wonder if the front wheel is on right, forks centered that type thing. So I look in the service manual for the axle torque spec's and pinch bolt spec. I loosened both pinch bolts, went to undo the axle and it was way over tight, suppose to only be 52 ft. lbs it was maybe 75. So I re-torqued it correctly and then I did the trick, lightly bumped the front wheel against the wall not using the front brake or anything like that. Just a bump with slight fork compression. This will center the axle on the fork bottoms. Then I torqued the pinch bolts in their prescribed method. Yamaha uses a weird 1-2-1 approach on this. Clearly states it in the sevice manual. Rode it 106 miles sunday and 46 miles to work on monday. What was leaking front forks on both sides is now only a sheen film left which may clear on a few more rides due to residual oil being there for 600 miles. So the moral of this story is center the forks on this thing or those low stitcion seals will weep. Seen this happen on many dirtbike swith inverted forks. Verdict is still out as to whether they will stop completely but it is 75% better than it was before I worked on it.

Damn Roy, I'm impressed :exclaim: I hope it did the trick and all that's left is the residue.

 

[elizilla]

I never had a bike with usd forks before, and haven't yet taken the Super Ten's apart. But I would assume it's like a conventional fork and has a dust cover, then a little air space, then the real fork seal. And if a fork seal is leaking, that space between the seal and the dust cover, gets oil in it. So even if the fork seal stops leaking, there will still be oil on the fork until all that oil works its way out from under the dust cover.

And on the conventional fork bikes I have owned, the dust cover can be pried up without taking anything else apart. The oil under it can be cleaned out. At which point, if the fork seal is now holding, it should stop weeping.

 

[roy]

USD forks work the same as conventional. You can pull down the little spring retainer carefully pry down the dust cover and there is the seal next. You can use old photo film or the wafer thin feeler guages and work them up and down around the seal and slider tube. Technically any debris will be forced out. Did this trick many times on dirtbikes with mixed results. I did take a look under the s10 dust covers and it's not wet at all. So hopefully this solves the problem. If not I will ship them to Ohlins USA fir a complete service. That is who does my racebikes in the past. Thermosman suspension is another good source for this work. I don't trust locals for suspension work. Too much can go wrong. If the front needs fixing I might as well match it with a Ohlins rear shock. I will wait and see how this goes first.

 

[Combo]

USD forks work the same as conventional. You can pull down the little spring retainer carefully pry down the dust cover and there is the seal next. You can use old photo film or the wafer thin feeler guages and work them up and down around the seal and slider tube. Technically any debris will be forced out. Did this trick many times on dirtbikes with mixed results. I did take a look under the s10 dust covers and it's not wet at all. So hopefully this solves the problem. If not I will ship them to Ohlins USA fir a complete service. That is who does my racebikes in the past. Thermosman suspension is another good source for this work. I don't trust locals for suspension work. Too much can go wrong. If the front needs fixing I might as well match it with a Ohlins rear shock. I will wait and see how this goes first.

I have purchased these.

http://www.sealmate.net/instructions.html

http://www.google.com/products/catalog?hl=en&xhr=t&q=dirt+skins&cp=9&bav=on.2,or.r_gc.r_pw.&biw=1920&bih=1003&wrapid=tljp1312907873380016&um=1&ie=UTF-8&tbm=shop&cid=12592440125712819275&sa=X&ei=ZmJBTprNIsHLsQKymcG2CQ&sqi=2&ved=0CEQQ8wIwBA#

 

[zman68]

I am 525 miles, rolled 300 today. Both forks are still showing oil rings on the slider tubes. Does not seem to be getting any worse or better. I plan to take it by the dealer next week. Weird how both sides are doing the same thing.

it happen to me and fork seal fail after 3000km...
still waiting for part to arrive..hopefully it's just improper installation in assembly line.
keep and eye on it..

 

[stevepsd]

I've done this for years....back in the day I used a piece of 35mm film as the seal scraper 'tool'. Works well. But I like gadgets (and tools) so I just bought a pair of the Seal Mate tools. Hopefully I won't need them, but they are pretty neat.

Now that I run the neoprene fork protectors, I have not had to clean or replace the seals on the KTM dirt bike in over 2.5 years (thats a record for me)!

I'm running the Kriega's on my ST http://www.kriega.us/off-road-enduro-motorcycle-fork-seal-covers/

-steve

 

[fredz43]

I am sure they do but evidently they were not used on my bike during assembly even with a yamaha parts/service rep there supervising the job. The old saying goes "if you want it done right then do it yourself" I am a firm believer in that statement. I have wrenched on bikes for years, road race bikes, dirtbikes and plenty of my own streetbikes. Worst experiences for me always go back to the initial setup at purchase time.

I guess the point I was trying to make is that not all setup persons follow all the steps in the published setup instructions. Takes a bit longer if you do.

 

[3putt]

My seals are fine, but I checked my axle just because. It was over 70 ft/lbs to break it loose. Rolled it to brakes making it dive several times before torque. There, now I feel better.

 

[colorider]

My seals are fine, but I checked my axle just because. It was over 70 ft/lbs to break it loose. Rolled it to brakes making it dive several times before torque. There, now I feel better.

I'm sure there is a relationship between original tightening torque to the torque required to break a fastener loose - but not sure what it is.

Anyone know what it is??

 

[rem]

I'm not familiar with fork seals. I think you may have these confused with Harp seals, which are indigenous to NE North America. Up here, it is illegal to own a seal, so I don't know much about them. I do know that they are very oily, but have never heard of one leaking. R

 

[3putt]

How is the weather up there Rem? Really would like to come visit, but parts keep coming in the mail to install on my bike. 106F here and we are 8 days away from breaking an all time record 45 days of over 100f in the summer. I grew up here and never remember this much heat, maybe it is a 100 year thing. ;D

 

[rem]

It's 34 American degrees here this morning. Come On Uuuuuuuuuuup. We were supposed to ride to Keno today but the lying weather vermin say it's supposed to rain for the next 4 years, so I don't know.


We'll see. R

 

[3putt]

34 American, I better put the heated grips on (in 106 degrees, are you crazy). Could use some of the rain from 1 of those years.