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Adjustable Front Forks Question

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Adjustable Front Forks Question


Post by dmf1 » Sun Oct 12, 2008 1:02 am

When I step onto my 59 pan that has a sidecar and adjustable front forks, I hear a hiss as air escapes out the vent holes and the forks compress almost to the point where they bottom out. If I hop a little, they do bottom out. I just replaced the fork oil and I don't have any leaks. Could to much air be getting out the vents for some reason? Is there another problem I could have or is this just how the forks ride with the added weight of a sidecar etc. Thanks

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Re: Adjustable Front Forks Question


Post by Panacea » Sun Oct 12, 2008 10:04 pm

Have you had the plugs out of the top of the tubes? There should be either a baffle assembly or a spring spacer which provides about 3/4" of spring pre-load. The cap has about 3/4" of threads so the spacer should sit on a washer on top of the spring and flush out to the top of the tube, so when the plug is screwed into the tube, will povide enough pre-load. You may need extra pre-load to compensate for the weight of the side car. Mike

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Re: Adjustable Front Forks Question


Post by 58flh » Fri Jan 20, 2012 2:31 pm

Check condition of baffle & like panacia said --If all your parts are inthere you may need additional --PRELOAD)--Richie---Also if you changed springs-- Make sure the right ones are inthere! I have had good results with PJ1 forklube-(amount plays a role here!)

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Re: Adjustable Front Forks Question


Post by RUBONE » Fri Jan 20, 2012 4:45 pm

The assembly should look like this. The valve is within the screwed in cap. the baffle stack is designed to seperate the oil from the air before it is allowed to escape through the valve. The valve is normally closed and should not open until the pressure builds up in the fork from operation causing heat and pressure build-up. It should not let air out when not in use! Standard springs with added pre-load will work best, progressive springs tend to be too soft on the extended portion of their range for SC use.

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