Yamaha xj 900 s Front fork oil amount in cm

Hi, all model VS 800 from1992-2000 take the same amount of oil in the front forks, using 10 weight fork oil measure into a clean measuring device or mark the side of the oil bottle 413 mls, pour this caerfully into 1 fork, and the same amount into the other fork, 413/413 cm (3)

Your front fork seal are bad and need to be replaced.
When you loose fork oil, your loosing suspension dampening and only riding on the springs.(POGO)

Replace both front fork seals and dust caps, and put same amount of fork fluid in both forks.

I bought my seals and caps for $30 on ebay, and then took my forks off my bike and took them to a shop and they charged me $75 to do the job.

You can take them the whole bike and they will charge $100 - $150 including parts to do the job.

491cc of 10w fork oil.

BUT, if you want it smooth, use lesser oil

if you want it hard, use enough to more oil.

no air on the fork mean no movement, make a note of that.

Manual calls for 10 wt
13.2 US oz
389 cm^3
or
13.7 imp oz

dissassemble forks and replace fork seals.(and oil) becareful forks are under a lot of spring pressue. use a workbench vise to hold fork tubes. you will need the manual for this. plus you will need to know the "proper" amount of fluid to put back into the forks.

you should change oil and oil seals at the forks