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Discussion Starter #1
I thought that I post up my latest round of messing about in my garage. (One day I might actually ride my bike!)

Anyway I have recently had my forks (2013 EXC) serviced and re-valved, I've not been out on my bike yet but I was a little disappointed by the stiction that the forks seemed to have, they were not great in this respect before I sent them off and they seemed worse when they came back. I don't want to moan about the chap that did the work because I feel it would be unfair, they may have been fine when riding the bike. He did apply a very light cross hatch pattern on the tubes but it was barely noticeable, I guess some people would not be happy with a dull looking tubes so he had a 'fine line' to tread (pun intended!). My simple test was to slowly compress the forks and see how far I could compress them without them springing back, this turned out to be around 20-25mm. (SKF seals and dust covers).

I then pulled the forks apart and applied a 'stronger' cross hatch pattern to each tube using 320 grit paper, even this fairly rough grade only leaves a fine cross hatch pattern on the tubes. I've rebuilt the forks but not added any oil yet. I can now only compress the forks about 5-8mm without them springing back, hopefully this simple mod will improve the 'floaty' feeling that I want to get from my forks. All the tests were done with the forks off the bike so bad fitting of the forks to the bike can not be blamed. I think that this is a cheap mod that is worth doing if you have the time and know some with a lathe!
 

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Do you oil the chrome? I’m a fan of a finger of oil over the chrome or DLC depending on the fork. I do this after cleaning when dry. Never had stiction issues? Be OCD on keeping seals clean so they don’t fill up and go tight. Never leave bushes in too long either. Apparently 10-15 hours max. I use mine longer than that though. You always notice an improvement with new bushes and oil. Never tried the cross hatch.
 

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Are you telling us that where the seals seal on the crome lower legs there is now a x-pattern in the chrome???
 

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Discussion Starter #4
Do you oil the chrome? I’m a fan of a finger of oil over the chrome or DLC depending on the fork. I do this after cleaning when dry. Never had stiction issues? Be OCD on keeping seals clean so they don’t fill up and go tight. Never leave bushes in too long either. Apparently 10-15 hours max. I use mine longer than that though. You always notice an improvement with new bushes and oil. Never tried the cross hatch.
I did use oil on the wet and dry whilst the tubes were spinning in the lathe but I then cleaned everything off because the wet and dry gunge would not be good for the seals. I did use some waterproof grease in the grooves of the seals but I think that it was a bit to sticky so I wiped most of it off. At the moment the tubes are bone dry and the forks feel good when being pushed down by hand, I think that they might be even better when the oil is added because it fills the cross hatching and lubes the seals. My forks have new bushes and when I tested the 'slideyness' of the forks without the seals they were as smooth as silk, it is definitely the seals and dust cover that creates the stiction.

I read up on doing this mod before actually doing it, some people reckon that over time you may lose a small amount of oil but really it should be replaced before that becomes an issue. Other people reckon that the cross hatch may hold dirt but it is so fine that I can't see that happening. Obviously I was a little worried about fucking up my tubes but I had a spare tube to I tried that before diving in on my actual tubes. It took about 10 minutes per leg at most and so far I am pleased! To measure the stiction I clamped the bottom of one leg in my vice with the fork upright, I then put a cable tie around the tube and pushed it up to the dust cover, I then pushed the top tube down a couple of mm at a time an then let it go, if it stayed in position I pushed it down another couple of mm and let go, at around 5-8mm of compression it then sprang back up leaving a gap between the cable tie and the dust cover the you can measure.
 

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Discussion Starter #5
Are you telling us that where the seals seal on the crome lower legs there is now a x-pattern in the chrome???
Yep, its very fine but you can see that its there. You would think that a polished tube would have the least amount of friction but this isn't the case. One thing that I read was to think of it like a windscreen wiper going over a dry windscreen, it judders and sticks. The cross hatch holds a very small amount of oil which stops the seal grabbing hold of the tube. Its hard to believe that it works but it does seem to!
 

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Discussion Starter #6 (Edited)
Here is one of the threads that I read, there are loads of vids and threads on doing this....


Some more gumph here...

 

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I might have let the new seals bed in with a couple of rides before deciding to do any more work. Just my opinion of course..
 

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Discussion Starter #8
I might have let the new seals bed in with a couple of rides before deciding to do any more work. Just my opinion of course..
Fair enough, and that's why I'm not going to moan about the guy that rebuilt my forks. Having said that he must have thought that the cross hatching is a good idea because he cross hatched them, I just cross hatched them more than what he did. I guess he could only give them a very gentle cross hatch because some of his customers might complain. Personally I think that when looking at them you can hardly see any difference between cross hatched and non-cross hatched. Also ultimately I want them to perform well, I don't care what they look like.
 

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What color have your dust seals? Black have the most resistance followed by green. The red ones apply least pressure to the tube...and get leaking faster than the other two...

I have heard about the micro polishing some time ago and it seems to be plausible. No forks manufacturer does it so far.
 

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Discussion Starter #10 (Edited)
What color have your dust seals? Black have the most resistance followed by green. The red ones apply least pressure to the tube...and get leaking faster than the other two...

I have heard about the micro polishing some time ago and it seems to be plausible. No forks manufacturer does it so far.
Hi Steveman, both the dust seal and the oil seal are green, I heard to opposite of you which is that the SKF seals (green) have the least stiction! Just goes to show that you can't trust anything that you read on the web these days! (including this).

Slavens has done a video on them and everything he says is totally true! (admittedly he is comparing them to the standard seals) LOL....

 

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I guess the cross hatching is absolutely tiny but for a trail rider like me all I think of is muck getting drawn in and contaminating the oil faster as well as taking the coating off the bushes.
lets be completely honest and say that on my trial bike it could 75-100 hours before I bother servicing the forks.... if the seals arnt leaking, I am riding! I factor in £90 for seals and bushes when they get serviced
I will say that after trying KTM oem seals and having them leak immediately I changed to green SKF seals. No more leaking.
 

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Hi Steveman, both the dust seal and the oil seal are green, I heard to opposite of you which is that the SKF seals (green) have the least stiction! Just goes to show that you can't trust anything that you read on the web these days! (including this).

Slavens has done a video on them and everything he says is totally true! (admittedly he is comparing them to the standard seals) LOL....

No problem. I was at KTM and that is what they said. No idea if their green seals are from SKF or if they are from another manufacturer.
I like the vid though it shows someone who is a cunt :)
 

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What color have your dust seals? Black have the most resistance followed by green. The red ones apply least pressure to the tube...and get leaking faster than the other two...

I have heard about the micro polishing some time ago and it seems to be plausible. No forks manufacturer does it so far.
So they use the red ones on the cone valve forks to reduce stiction? Can also confirm that they leak quicker...


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So they use the red ones on the cone valve forks to reduce stiction? Can also confirm that they leak quicker...


Sent from my iPhone using Tapatalk
My cones have red seals. They don’t seem sticky in anyway but the forks sure can leak easily for no apparent reason. Not lots of oil but a tiny bit of creep on the coated lowers. No idea why but it doesn’t do it as much if Iet the extra air build up out after riding.....sometimes. I wondered if the coating on the lowers and seals is to slick? Oil simply migrates past three seal- definitely no stiction.

My remedy is keep lowers and seals clean between rides, bleed air out. If they do get any leaks just bounce them up and down and it stops. Weird. I can see why people could be frustrated by this but it is tiny amounts of oil.

My spheres on the other hand never leak (stock tubes with chrome lowers). Seals (red ones) wear out on these and still no leaks. They also have no obvious stiction.

To me it seems that stock tubes just leak less and are far cheaper. Cones are mind melting expensive so you get a lovely feel and they are easy to work on. You also get lots of adjustability but also get leaks thrown in to the deal?
 

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Aye, there’s the rub... excellent forks though. You’ll know you’ve got them and be glad when you’re flat open and hit a tuft of camel grass you didn’t see... would end you on stock suspension.


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So they use the red ones on the cone valve forks to reduce stiction? Can also confirm that they leak quicker...


Sent from my iPhone using Tapatalk
It seems so. My suspension friend says it is a logical consequence....
 

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Last time I spoke to Brokenlegs on the subject, he said that the KTM seals are SKF but double lipped. The standard SKF seals are single lipped as KTM has an exclusive deal with SKF.
 
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