[scotty97]

After taking my bike off a trailor on saturday, i noticed a bit of oil on the fork seal on the one leg. the tubes are normally clean and theres been no evidence of a leak. could i have compressed the suspension too much using the straps on the trailor because the seals were inspected the same day during my MOT and were good, and i only put the bike back on the trailor and brought it home???????

[shercofray]

the seals can break for a number of reasons but compressing when you compressed the forks alot there may have been a mark further up the stanchion and this could have broken the seal

[scotty97]

im hoping like you said that there might have been a mark and by compressing the forks and holding them in that position has caused a little bit to leak. there was only a tiny bit on top of the seal. the leg itself was dry

[shercofray]

no the seal will be leaking now and you will have to replace it, this is because when the leg slides in even the smallest mark can rip the seal and allow oil to pass through it

[scotty97]

Typical, i'v only had the bike a few weeks, is it a big job??????????

[shercofray]

not a major job but it involves taking the legs out, draining the oil, and then changing the seals, simple when you know how

[trialsnutterman]

You can quite often get a bit of muck trapped under the seal, try removing the dust seal and give it a good clean then using a small feeler gauge go around the oil seal to fetch any trapped muck out.

If you have got a nick in the leg fill it with super glue and using a very fine oil stone smooth it off before putting new seals in.

[scotty97]

What spec oil do people use in the forks?? im about 13 stone.

At the moment the fork set up is spot on, if I leave all the settings the same and just change the oil and seals will the forks feel similar to how they are set up now????????

[copemech]

scotty97, on Apr 22 2010, 12:33 AM, said:

What spec oil do people use in the forks?? im about 13 stone.

At the moment the fork set up is spot on, if I leave all the settings the same and just change the oil and seals will the forks feel similar to how they are set up now????????

5 wt oil is standard, should be fine. You can use a dull flat blade to tap the outer dust covers up to dislodge them, then inspect/clean what is underneath them on the seals.

As trialsnutterman stated, a thin feeler guage or an old 35mm filmstrip can often be used to slide round under the actual seal lips to get crud out.

Results vary, yet takes only a few.

[scotty97]

Took the bike out yesterday for a couple of hours, and its leaking quite a lot through the fork seal, it was actually running down the out side of the bottom part of the forks. Spoke to the local trials shop and they said they'd service the forks for me, it'l cost me the price of the fork oil, the seals and about £20 odd labour. Atleast i know they'll be done tidy then and because i hav'nt had the bike long, i dont know whens the last time the fork oul was actually changed.

[madbob]

What year is the 290 is it the type with the blue plastic caps on top of the forks ?
I had the same problem as you when i tied my 2001 sherco 290 down hard on my trailer after not having it long.
I suspect my fork seals were old and it had been standing for a while before i bought it but the air pressure being held for a long while didn't help.
I replaced the seals and changed to a 5w for 2 weeks which seemed a bit soft and then tried 10wt which seemed a little hard.
I allready had plenty of fork oil so did a 50-50 mix to make 7.5wt and it was much better. I was supprised that i could tell the difference to be honest.
If it is the type with the top blue caps i slightly unscrew my ones when i strap it down now and tighten them back up once it is off the trailer.

If you go to the sherco site and the then the support tab and then Waynes help there is a guide to changing the seals.

http://www.sherco.co...Replacement.pdf

Rob

[scotty97]

No, the forks on my 2007 sherco 290 are the ones with the red rebound (allan Key) adjuster on them. I've also noticed that my forks only seem to travel half the distance that they are suppose to, i checked against some on elses bike and theirs seemed to have double the travel. i have not touched the fork adjusters since buying the bike, as the forks feel tidy, a nice quick rebound just as i like it and tidy compression setting but they deffinatly should be travelling further. they do not bang to a stop as if they're bottoming out but its like as if they get really hard gradually until they cant go down any further. anyone got any ideas on this????????

[tony27]

Sounds like the cartridge didn't get emptied of oil & when the amount in cc's was added you've ended up with less air gap, always safer to use the oil height with the springs out & fork compressed to get the correct amount of oil

[scotty97]

Forks are not leaking now, so looks like there was a bit of sh*t in the seal and its out now. But im convinced they should be travelling a bit further so after reading what TONY27 had to say about amount of fork oil im going to have them serviced anyway. Just spoke to the mechanic and he said he always measures the air gap and not the amount of oil, so atleast i'l have new seals, new oil and the right amount of oil put in. Looks like a night in the garage tonight then!!!!!!

[hermancremer]

does anyone know if there are after market fork seals for an o6 model ?
or if someone has the dimensions that would help a lot !
thanks

This post has been edited by hermancremer: 07 September 2010 - 12:14 PM