Trying to do as much maintenance on the bike as I can and while installing a new front tire I decided I might as well change the front fork tubes oil. The reference owners manual I found online for my 2001 Rev3 with Paioli forks says 60 mm from top fully compressed on the right side and 120 mm from the top on the left (spring) side. It does not indicates to compress the spring side tube for this spec. Does that sound right? I don't want to end up with too much oil and ending up blowing up the seal or worse.

The instructions below clearly ask for the spring to be inserted back in the tube and the picture shows the spring inside the tube in what appears to be a fully extended position. (I just can't copy the picture to paste here from the pdf.)

Left shaft

To replace the oil, proceed as follows:

1) Remove the front wheel

2) Remove the handlebar (see pag. 65)

3) Unloose the shaft lock the screws A

4) Unscrew slider plug

5) Remove the spring and totally empty

the oil

6) Reset the spring and fill with oil

(OJ01 ) up to the level indicated in

figure

Note:

120 mm Oil level 7W fork oil.

Anyone can confirm this? Replies are appreciated, Thanks!

BTW, when I drained the fork I got some 300 ml out which is what Jim at the Gas Gas USA site indicates to use on their bikes. I just don't know if these are the same forks as used by Gas Gas in some of their older bikes. To get to the indicated 120mm from the top fully extended will take some 400ml. I can go back with 300 ml but that is part of the reason I am doing this as the front end felt a bit weak/soft. My weight is 76 Kilos with gear, in case that it matter

Edited July 2, 201115 yr by Rainmeister

After some research on this forum the best answer appears to be:

from the manual ,,,

- right leg ................................................370 cc

- left leg .................................................350 cc

There is a lot of debate about the accuracy of the manual picture showing the spring in the "fully extended" position but the volume measurement is referenced by many. The procedure has been updated in more recent bike manuals and it clearly shows the left side fork w/o the spring for the final gap measurement.

A couple more quotes from Trials Central:

"The Beta manual is wrong - it shows measuring the left fork with the spring installed and fork leg extended. In order to get 120mm from the top of the tube it takes about 500cc of oil which is way too much. Spring out and fork leg compressed all the way then measure 120mm to the top of the tube."

Procedure recommended:

Oil level is measured with:

(1) the upper left fork tube collapsed into the lower leg.

(2) the internal cartridge completely bled of any air.

(3) the spring removed.

(4) level measured (120mm) from oil surface to top of upper fork tube.

and that is what I going to go with!

That is how I did my 2008. Make sure and pump all of the air out of the right fork before measuring the height. It seemed to take a while. Set up like this, it was a little harsh for me (at 155 lbs). I lowered the height in the left tube from 120 mm to 5" and it seems just right.