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Riding Styles => XC => Topic started by: atvmxr on November 17, 2020, 03:10:43 PM
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I dont know if all XC are like this, but I finally got all my stuff to be legal to ride the national forest in texas. lots of big sand whoops like you find on dune trails, but also tons of 3-4" tall tree roots that were basically like ridding a trail scattered with bricks. Very square edged and constantly yanking the bars around. Im sure a steering stabilizer would help the side to side, but I want to ask about shock brand/rebuilder that set up shocks for really rough low-mid speed stuff, but still be able to handle jumps and whoops like you find on MX.
?
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Atvmxr, What did you change to be trail legal?
Joe
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I dont know if all XC are like this, but I finally got all my stuff to be legal to ride the national forest in texas. lots of big sand whoops like you find on dune trails, but also tons of 3-4" tall tree roots that were basically like ridding a trail scattered with bricks. Very square edged and constantly yanking the bars around. Im sure a steering stabilizer would help the side to side, but I want to ask about shock brand/rebuilder that set up shocks for really rough low-mid speed stuff, but still be able to handle jumps and whoops like you find on MX.
?
Even though you may be hitting the tree roots at low MPH, the shock action moves the shock piston in the high speed mode where a lot of fluid needs to flow through the piston without generating very much compression damping. This requires a compression shim stack that can open wide without needing a lot of pressure to lift the leaf valves.
Woops and jumps moves the shock piston relatively slow and needs a lot of compression damping to provide more resistance to bottoming as compared to hitting the tree roots.
I do not know of a compression valve plate stack that will handle both extreme ends of the requirements you stated. I have seen and tried a lot of "progressive shim stacks" but have yet to have them work like theory says they should. Gas pressure should not be used as a tuning tool but lowering the gas pressure will usually improve the square edge shock response, but when the gas pressure gets too low, the shock will turn into a pogo stick. There is a fine line of finding just the right gas pressure and the shock becoming a pogo stick.
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I dont know if all XC are like this, but I finally got all my stuff to be legal to ride the national forest in texas. lots of big sand whoops like you find on dune trails, but also tons of 3-4" tall tree roots that were basically like ridding a trail scattered with bricks. Very square edged and constantly yanking the bars around. Im sure a steering stabilizer would help the side to side, but I want to ask about shock brand/rebuilder that set up shocks for really rough low-mid speed stuff, but still be able to handle jumps and whoops like you find on MX.
?
Might be helpful to talk to a reputable shock builder that does a lot of XC stuff. Derisi is the first builder that comes to mind.
Are you running Flexx bars or a precision bar mount? That might help on the smaller stuff too. Flexx bars work wonders for me
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Even though you may be hitting the tree roots at low MPH, the shock action moves the shock piston in the high speed mode where a lot of fluid needs to flow through the piston without generating very much compression damping. This requires a compression shim stack that can open wide without needing a lot of pressure to lift the leaf valves.
Woops and jumps moves the shock piston relatively slow and needs a lot of compression damping to provide more resistance to bottoming as compared to hitting the tree roots.
I do not know of a compression valve plate stack that will handle both extreme ends of the requirements you stated. I have seen and tried a lot of "progressive shim stacks" but have yet to have them work like theory says they should. Gas pressure should not be used as a tuning tool but lowering the gas pressure will usually improve the square edge shock response, but when the gas pressure gets too low, the shock will turn into a pogo stick. There is a fine line of finding just the right gas pressure and the shock becoming a pogo stick.
Thank you for the explaination
Atvmxr, What did you change to be trail legal?
Joe
Well the main thing was finally taking that ATV safety class. put on a FMF Q spark arrestor silencer. Texas OHV sticker
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Like jerry said what I have requested to meet my needs in woods racing you cannot have the best of both.