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Lots of fork stiction on RM250….how to fix?

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I picked up an 04’ RM250 with the 47mm forks.   The forks seems to have a lot of stiction. When I set on the bike, the back will drop down to a good rider sag (around 100mm), but the front forks don’t seem to sag at all when I sit on the bike unless I really bounce on them….then they settle down to the proper sag.  Is that common to have that much stiction on the forks?  Could the seals just be dirty and full of junk?

Thinking about pulling them apart this weekend and putting fresh Silkolene Pro RSF 5wt in the forks…..maybe fresh oil will smooth things out?

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The guy I got the bike from said it was set up for his weight (210)....and that's what I weight. I might pull one of the springs out and see what it is. Are the springs marked at all?

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Could be dry seals, worn bushes, bad fork alignment

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The alignment is good, but I'm going to check out the seals tonight. It might be a good time to just pull the forks apart and put some fresh fluid and seals in them and give them a good cleaning.

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Bushes more than 25 hours old ?

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Alignment may look good,  but you don't really know if it is,  or I should say I don't know if it is unless I go through the complete ritual.   The springs will depend on who sold he springs and my have some color codes on them.  Look to see that they are the same length,  as they sack at different rates.     Good time to do as you say and pull them down and check it all out.   Nice way to get to know it :ride:

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Triple and quadruple check the alignment at the axle on the front end.  I had to lathe a couple mm off the right side front axle spacer to allow the right fork leg to get proper alignment.

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Loosen right side axle clamp.  Pry apart gently with a SMALL screwdriver, let it float and find its center.  You should see a few mm of the large part of the axle sticking out of the lug before the spacer.  If the hub spacer butts up against the lug with no axle showing, it's definitely out of parallel.

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Well, I cleaned the seals.....loosened up the axle bolt and checked for alignment issues (it was good), and bled the air out of the forks.  All of that might have made a small little difference....but they still feel really sticky.  I think I'm just going to pull them apart and put new seals and bushings in them and also see what springs are in them.

It's got a full Pro-Action suspension setup....so I'm interested to see what's actually inside of the forks as far as the valving goes.

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I have an ocd fork procedure, tighten non brake side pinch bolts, tighten axle, loosen non brake side bolts, tighten brake side bolts, remove fork caps, raise front wheel  till forks are bottomed out Loosen all the triple clamp bolts, make the fork heights match, tighten all triple clamp pinch bolts to torque value.  Tighten non brake side bolts. Lower front wheel, screw fork caps back in.

This is THE most accurate fork alignment procedure there is.

You can measure the position of the axle in relation to the fork lug with a depth mic so you don't have to repeat this PITA

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I don't think it's an alignment issue.....I checked it, and everything seems good. I think it could be a bushing issue. The bikes an 04'....so who know's when they were changed last. They just feel really sticky......

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