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Hi all, new guy here 😀 Was recommended to ask here for a little advice on servicing my forks.
Forks are fox f100 rl open baths that came with my 2011 anthem. After 4 months of use and having done nothing but use fork juice on the stantions between rides ive done a lowers service and oil change.
Everything went smoothly and as far as im aware the fork is performing as usual. However thinking about it afterwards i've got a few questions that need answering to put my mind at rest.
Firstly, when i removed the old oil i'm fairly sure it was a lot less than the 155ml/20ml per side that the oil volume table recommended. Perhaps about 100-120ml instead. I then added the recommended oil volumes to each leg but my worry is that i may not have got all the oil out as i've seen some posts say you should cycle the damper to help drain it, instead i just held it in a bike stand with the lowers off and let it drip out. Would have too much oil in the fork have any ill effects? If so i'll go and double check tommorrow but i'd just like to check im not being a numpty.
Secondly the fox guide says to pour the damper side oil through the top cap, whereas the guide i followed said to pour it through the hole at the bottom of the lowers. Is the whole side of the fork just one big chamber so it doesnt matter what end you pour it in or have i done something very wrong?
Thanks all for the replies, hoping its just me being paranoid! 🙂
The damper assembly will retain about 10ml of the old oil in there if you don'tcycle it and lift the shim at the footnut end to release it.
Plus, as an open bath damper lubricates the stanchion and bushings, you don't need to add the 20ml oil bath on the damper side. That's for cartridge damper forks like the FIT versions.
The result is you've probably got 30ml too much oil in the bath which will lead to hydraulic lock between the mid and endstroke phase. You won't get full travel out of the fork in this situation.
A quick and easy way to check, is to deflate the spring and compress the fork to see if it locks before full travel. If it does, try removing the topcap on the damper side and syringe out the excess 30ml, refit the cap and repeat the compression exercise until you get full travel. Then inflate the spring, engage the lockout, and check the fork locks at full extension to check you've not removed too much oil.
Or strip it down again and replace the oil to the correct levels.
HTH.
Hi, thanks for the response.
Just done the check, i'm fairly sure i have got full travel on it (theres 102mm of stanction visable and when fully depressed there's 6mm visable.
So i'm assuming that's close enough to 100mm of travel. Seems like the oil levels are alright then, i'll double check next time i service the seals anyway to make sure (which won't be long considering fox's service guidelines)!
Most fox forks run 160ml in the damper leg. So I guess the 6mm shortfall is the resdiual oil in the damper. I guess you only added the 20ml in the spring leg as you should have, it read as if you'd added it to both in your post.
You should be fine to run with that until your next 25hr oil change.
(these intervals are for the spring leg only as the oil bath is a small volume. It can get to 15hr intervals for TALAS versions with only 10ml in the spring leg bath)
They are high maintenance, but the high speed compression damping is so good, I wouldn't use any other fork if I didn't have to.
RS don't have high speed compression unless you mod them as I've done with some Pikes fitted to my HT.
Then they work real nice. Almost as good as Fox.