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manwithtool

Fork Seal Maintenance And Rear Master Cylinder Maintenance

4 posts in this topic

Mixed bag of subjects....but having just replaced my Evo fork seals ( a job I hate doing) it strikes me that an awful lot of crud builds up under the dust caps....Does anyone prize these things of anc lean under them ? should you spray WD40 in there ? I was told WD40 makes the seals swell up ?

Also just about to replace the rear master cylinder on the EVO, this seems to a leak letting a bit of air in and some fluid out. How does that wear out in 3 years ? it's pretty well protected. Lampkins did advise squirting WD40 up there to flush out dirt and lubricate. Anyone do this ? and again WD40 affecting the seals ?

Maybe I've been missing a bit of vital maintenance on my bike here ?

Love to hear other peoples comments or advice on making these bike last a bit longer !

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The Standard Paoli dust seals are terrible, SKF's are much better, The problem I have found with the original dust seals is that they have a slight gap around the inner edge of the fork leg, Which allows loads of muck to get underneath them, The SKF seals fit much better & they have no gap on the inner part, If you have the standard seals in though, Keep lifting the dust seals up now & again and blow all the dirt out.

As for the rear brake master cylinder, I've never had any issues with the one on my Evo, I just look after mine by pulling the rubber seal off the bottom of it & use the air line to blow all the muck out of it, & I also put a small cable tie around mine to seal it a bit better. Using WD40 would be fine as well.

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Them fork bootie things work well at keeping crud out. Specially if you ride in the mud a lot.

Ck outer rubber on MC for tears due to rocks and debris. If it is grunged up inside there is likely a hole. Once repaired, pack the inside with silecone grease as a preventer. It is inert to the rubber components.

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I always slide up the dust wipers afet a ride and leave them up till next time. This lets the seal retaining clip area dry out and lets you do the feeler gauge trick to clean them both out (seals and wipers).

Once cleaned, bounce the forks up and down to settle them and get a good seal again. Wipe the legs clean and bounce again - you should get no oil on the legs. Leave the wipers up and let the whole job dry out during the week.

Mine are the original seals and wipers from 2007! The wipers and seals will be repalced this year for the winter as my wipers are just beggining to get to the point that dirt can make its way past - probably explains why I need to clean the seals and wipers every ride.

10 mins in the workshop and they both last a long time. I'm not a fan of covering up forks as you can't see any issues soon enough and it creates a damp atmosphere behind them.

As for the brake a little maintenance goes along way - strip & clean out with an airline or clutch/brake cleaner. Re build the components using waterproof greas such as Silkolene R2 (which you use for swingarm bearings etc). Do this after really wet and muddy trials (or a full on pressure wash) and it will last a long time.

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