jandyb Posted August 17, 2008 Report Share Posted August 17, 2008 (edited) I`m in the questioning mood these days.. Hope that any of You "gurus" can answer.. The front suspension on my sons 06 125 pro Racing feels a bit stiff. Much stiffer than my 04 300 even when the adjustment is at softest setting on both forks Since I don`t think the fork oil is ever changed I thought I would go for some fresh oil. I`m not sure if new oil would make it softer, but it would definately not hurt. First thing I did was to go for the oil draining skrew at the bottom of the forks. Surprisingly they was not there. I guess You have to take it out and turn it up side down to pour out the old oil? OK.. second i was about to remove the top cap on the forks. Surprised again I found that the 17mm "bolt head" on the right fork was turning like it is supposed to adjust something. In that case what? The spring maybe? If so why not on the left fork also? And last why doesn`t the manual say anything about this? Still if the "bolt head" is some kind of adjuster how do I get the top cap off? Special tool? On the left fork the "bolt head" and the top cap is one. Can I use the 17mm to loosen the top cap here? Heres a cut out of the manual from 08. It is similar to both 06 and 07. It shows 2 different fork types. The one on the left is similar to the forks on my 04 300 and the ones to the right is like the ones on the 06 125. I guess the one to the left has not been used since 2005. What the h**** does this picture do in a 08 manual anyway? -Jan Edited August 17, 2008 by JanDyb Quote Link to comment Share on other sites More sharing options...
sectionone Posted August 18, 2008 Report Share Posted August 18, 2008 I have a quick and easy method to change the oil in the compression side for the aluminum forks. Remove the allen bolt at the bottom of the fork, loosen the fork cap all the way and unscrew the air bleed screw. The fork cap won't come all the way off but the oil will drain from the bottom which you should collect in a measuring cup. Replace the bottom bolt and tighten the cap. Take a big syringe and replace the same amount of fork oil that drained, through the air bleed hole, then replace the screw. If you want softer compression, use less oil and/or 2.5 weight oil. The correct way is to disassemble and measure the oil level but I'm too lazy for that. The rebound side is a mystery to me. Very little oil drains when you remove the bottom bolt and you need a special tool to remove the cap. A tool with pins that fit in the 10 little holes in a circle. Does anyone know where to get one? Quote Link to comment Share on other sites More sharing options...
jandyb Posted August 21, 2008 Author Report Share Posted August 21, 2008 I have been doing some research on this.. The "bolt head" on the right fork is supposed to adjust the spring preload. Testing both the hard and soft ettings I could not notice some change anyway, but the thought is good... To remove the cap one need a special "pin tool", but I think I will figure out some way to manage without... My dealer recommended that when the forks are off the bike and opened I should take them all apart (not the insert though) to ensure that the stiffness is not due to dirt. -Jan Quote Link to comment Share on other sites More sharing options...
jse Posted August 22, 2008 Report Share Posted August 22, 2008 I have been doing some research on this..The "bolt head" on the right fork is supposed to adjust the spring preload. Testing both the hard and soft ettings I could not notice some change anyway, but the thought is good... :)To remove the cap one need a special "pin tool", but I think I will figure out some way to manage without... My dealer recommended that when the forks are off the bike and opened I should take them all apart (not the insert though) to ensure that the stiffness is not due to dirt. -Jan Jan, Just to eliminate misalignment as a possibility (it can cause forks to feel "stiff"), you might want to loosen all the fork fasteners (and take off the fork brace) except for the top tripleclamp bolts, push down on the forks to center them, torque the lower tripleclamp bolts, pump forks again, tighten the axle clamp bolts, center forks again and install the fork brace. Essentially, tighten the fork fasteners from the top down (except for the brace, which should always be tightened last. If the brace holes do not line up, use a small round file to open the holes so the capscrews drop in easily. Any good tool store should have a "pin spanner" type wrench, which is adjustable to fit caps like the one on the Marzocchi's. Jon Quote Link to comment Share on other sites More sharing options...
jse Posted August 22, 2008 Report Share Posted August 22, 2008 I have been doing some research on this..The "bolt head" on the right fork is supposed to adjust the spring preload. Testing both the hard and soft ettings I could not notice some change anyway, but the thought is good... :)To remove the cap one need a special "pin tool", but I think I will figure out some way to manage without... My dealer recommended that when the forks are off the bike and opened I should take them all apart (not the insert though) to ensure that the stiffness is not due to dirt. -Jan Jan, Just to eliminate misalignment as a possibility (it can cause forks to feel "stiff"), you might want to loosen all the fork fasteners (and take off the fork brace) except for the top tripleclamp bolts, push down on the forks to center them, torque the lower tripleclamp bolts, pump forks again, tighten the axle clamp bolts, center forks again and install the fork brace. Essentially, tighten the fork fasteners from the top down (except for the brace, which should always be tightened last. If the brace holes do not line up, use a small round file to open the holes so the capscrews drop in easily. Any good tool store should have a "pin spanner" type wrench, which is adjustable to fit caps like the one on the Marzocchi's. Jon Quote Link to comment Share on other sites More sharing options...
sectionone Posted August 27, 2008 Report Share Posted August 27, 2008 I found the tool to take off the rebound side cap. It is called an adjustable face pin spanner. Make sure you get the 3mm pins. I got mine here for $12. http://www.reidsupply.com/detail.aspx?R=AM...20pin%20spanner Made in Germany by AMF (Andreas Maier Fellbach) Quote Link to comment Share on other sites More sharing options...
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