Hello all

I thought I was going to have to replace my fork seals as the one started to leak slightly. I did lose some fork oil as she dripped a small puddle on the concrete floor in the garage after sitting a week. I did the the ole swipe trick with a thin piece of plastic to clean out any debris in the seal.
To my suprise it worked. Just drove her 30 miles with no oil ring or residue on the fork. Apparently there was some debris in there that got pass the dust seal. But its now in the oil somewhere.

I need to balance the fork oil since I lost some so i figured a change the oil and then add in the correct amount for each side. I found the drain bolt on each fork. But where do I add the oil. Do i remove the top bolt and air valve and add it there? Seems the only place it could be. The manual doesn't say anything about it.

 

yes you add through the top bolt/air valve. The guys at sonic springs recommend a distance from the top rather that a total volume. I went with 125mm for the oil level. So the oil starts 125mm from the top of my forks. Motion pro makes a fork oil level tool that makes it real easy. I will happily lend you mine if your not to far for the shipping to cost more than the tool.

 

Thanks for the offer. I may take you up on that. I was going to go by the recommended volume in the manual and then add some oil if needed to firm up the ride. When you fill the forks with oil should the front wheel be suspended so no weight is on the forks? I was also going to use ATF oil as alot of people recomend that as long as its 10w. Your thoughts on that.

 

If you are going to go for a level like I did you check the level with the forks collapsed and no springs. If you are going to fill a capacity I don't think it matters. I used 10w fork oil, and have heard that you can use tranny oil. I don't think it really matters, for me fork oil was not that expensive and I had no worries.

 

Be sure to support the bike, when taking off the caps. You might try doing one at a
time, so the opposite fork supports the bike, But I still recommend an additional method.

Also, use caution removing the cap, sometimes there is spring pre-load on them.
If you aren't careful, the cap will shoot across the room as you turn that last thread
out. doh!

Pmcg is correct on properly measuring the fluid.
When measuring fluid, it is with the springs OUT. When pulling the spring,
note which way the end of the spring, with the tigher coils, goes.
It usually goes in first, but I won't swear that's true in all cases.

The easy, cheap way, to assure proper level...get a turkey-baster and some tubing.
Attach the tubing to the baster and measure/mark the free end with tape at the
correct distance. Over-fill the tube, and then place the hose into the end,
with the tape at the top of the tube. Draw out any fluid that you can.
It will stop drawing when the fluid gets to the bottom of the tube.
I believe that's the basic idea with the specialty tool.

Re-install the spring and cap. Done.

One thing to consider, if you're going to this much trouble...Use the baster to first,
draw ALL of the oil out. You might as well do a complete change, it won't really cost
much more, and can't be a bad thing, maintenance-wise.

Ern

 

Thanks for the information from you both. I haven't priced fork oil but will do so this week. If its only a few dollars more I ll go with the fork oil.

I was thinking about measuring the fork oil from the fork that was not leaking when draining so I would know what to put back, but I got the manual. I may do so anyways just to see how close it is in volume compared to the manual.