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47mm showa twin chamber forks home made tool to pull small amounts of fork oil needed

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Have an 06 RM250 installed stiffer front springs for my weight and running 370cc's of fork oil (10cc less than stock) I feel I need to remove more oil the forks have a hard time working in the midstroke on anything but a hard impact. I can especially feel it on jump faces and whoops it doesn't want to move very well.

Does anyone have any ideas/advice on making a home made tool to accurately pull like 5cc increments of oil out of the fork to make the bike work better in the mid stroke? I feel my forks have too much oil in them still hence the brutally harsh midstroke action

Any ideas/advice would be greatly appreciated....thanks!

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try to take off a 20x0.10 from mid valve

While I am competent enough to do this I never have can you point me in a direction to learn how to do this? I would really like to learn how to alter my own suspension I understand how the shims work and oil flows just need to know how to work on it

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350cc is stock oil volume on an 06 RM250 👍

Just pull the bleed screw out and slowly pour the oil out into a graduated cylinder.

Does this work on TC forks?

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Yeah, you're adjusting the oil height of the outer chamber

The fork vent goes directly into the top side of the free piston, how does that make it to the outer chamber. I know there are holes that connect that area to the outer chamber, but does it matter that all that oil sits on top of the free piston? Just wondering... I guess it could be argued that since the top of the free piston and outer chamber are vented together, then more oil, weather it sits ontop of the piston or in the outer chamber, is still taking up space that would be otherwise filled with air, thus decreasing the airspring volume...just never thought of it.

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The fork vent goes directly into the top side of the free piston, how does that make it to the outer chamber. I know there are holes that connect that area to the outer chamber, but does it matter that all that oil sits on top of the free piston? Just wondering... I guess it could be argued that since the top of the free piston and outer chamber are vented together, then more oil, weather it sits ontop of the piston or in the outer chamber, is still taking up space that would be otherwise filled with air, thus decreasing the airspring volume...just never thought of it.

To be honest, I wouldn't have thought of it either, but that is what is shown in the service manual!

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... I guess it could be argued that since the top of the free piston and outer chamber are vented together, then more oil, weather it sits ontop of the piston or in the outer chamber, is still taking up space that would be otherwise filled with air, thus decreasing the airspring volume...just never thought of it.

right 👍

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try to take off a 20x0.10 from mid valve

Cardinale hit it right on the head with this bike. It had a strange midvalve with .15 float. The trick I got from Ferg was to remove (2) 20.10 and replace with a 20.15 This increased the float to .20 and fixed most of the problem. I also found that anything above 350cc would make the fork useless.

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I use 360cc normally as a start point for showas but my personal rmz has 310cc

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Thank you to everyone for the input I think I had my mechanic put in 370cc's by mistake and that would totally explain all the problems with the midstroke being non existent..... I'm going to go down to 345cc's and see how I like it..... I'll bet its going to make a HUGE difference. Thanks again everyone

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Correction that was for a set of forks on my old 250f .... I am running 350cc's right now may need to drop down to 340cc's and see how it feels because as of now since rolling the bars back I have taken weight off the front end and unloading the compression makes the bike stinkbug they just don't work very well but I do like the balance after moving the bars back just need to get the suspension dialed

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Revalving rmz's seems to be a sticky situation, Suzuki likes to run high oil heights stock and while that makes suspension slightly firmer then most are used to, I have found that running one or two less face shims then I would in another bike with showa twin chambers and running high oil yields better results than running a usual stack and lower oil heights

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mine uses one less 20 on the mid , so more float , a small stack of 0.1s on the base and stiff springs for my weight so that's the reason for the low oil amount

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mine uses one less 20 on the mid , so more float , a small stack of 0.1s on the base and stiff springs for my weight so that's the reason for the low oil amount

Thanks for the info ..... I am about nov/int speed in mx speed and replaced the stock springs with .47's and a 5.4 in the rear 350cc of oil after last night I found my settings were waaaay off from stock per the manual so I went back to exactly what the manual calls out for an 06 rm250 ....as a rule of thumb when going up 2 spring rates from stock should I adjust my clickers to work with the heavier springs or stick with stock and tinker? I was just wondering if anyone had any settings or suggestions on where to go from stock settings sorry don't have the manual in front of me but any advice on a setting with clickers or a rule of thumb to follow when installing stiffer springs would be awesome. I know its a broad request but any input would be appreciated ....typing from my phone so I apologise in advance for typos 👍

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normally I would try 2-3 out on comp and 2-3 in on rebound , www.mx-tech.com has a tuning guide that could assist

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