Fork oil advice

Just about to fill the jr t,s with oil. Marzocchi recommends 160 of 7.5w in each leg. I'm assuming that would equal 320 ml from a 500ml (half litre) bottle or are they using some strange measurement that only exists on the moon? I.e. 160ml per leg

To be clear, you mean 160mm (milli-metres) = 160ml (milli-litres) ? no

None of my manuals mention quantities, just heights. Fill, measure, repeat.

It's all done on height... x mm from the top of the stanchions when the forks are compressed and the springs are removed. If you look on the Windwave website there is a chart for all of the forks.

I've always found it best to compress and extend the fork a few times when filling it up. Without doing this the fork has felt too fast so I've had to run lots of rebound. It seems to ensure the damper cartridge gets full too.

.... don't make the mistake I made and fill the fork legs up to the top ..... and then wonder why they wouldn't compress.

Mindmap3":64cdw3fm said:

It's all done on height... x mm from the top of the stanchions when the forks are compressed and the springs are removed. If you look on the Windwave website there is a chart for all of the forks.

I've always found it best to compress and extend the fork a few times when filling it up. Without doing this the fork has felt too fast so I've had to run lots of rebound. It seems to ensure the damper cartridge gets full too.

Click to expand...

Yes it pumps the air out trapped in places.
But don't do it too fast as it can blow the oil out.

Vernier callipers come in handy for oil heights, or a skewer with half cm marks on them.
I know on the turn of the 00's and earlier you can adjust the oil height to tune the spring rate slightly to compliment the metal springs as the air is still acting a bit like a spring (it's in their Tech docs)

Some forks do use XXcc of oil. Certainly Marzocchi turn of the 00's air/oil forks.

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Anyway just a thought, no idea what era your forks are but if not too new then try this,it'll give you some insight anyway .
http://www.retrobike.co.uk/gallery2/d/1 ... f72e652733
I think there are some other techy ones for other eras on the net as well.

^^^ thanks for that .... looks like i'll be refitting my red springs plus checking oil height tomorrow.

hi sorry they are stamped 97 so from the 98 range. on the windwave website it doesn't list a height just a volume which says 160 per leg. just out of interest when I drained the old oil out it stank to high heaven, I mean like dead people stink so I cleaned everything and pit new seals in there as one was leaking real bad. I got some 7.5w rock oil motorcycle racing synthetic suspension oil. all the internal components look good and the gold anodizing on the sliders was in good condition. the only strange thing was according to the manual breakdown picture in each leg it build up as a pumping rod with a collar and a short spring then a seal then a washer then the real long spring then a black plastic hollow tube then the compression adjuster at the top. when I took these apart everything was there in the correct place other than on top of the long spring there was a washer with another short spring then the plastic hollow tube. so in essence an extra 1 inch long spring in each leg. these springs don't appear in the service manual everything still fits and seems to work ok just a bit odd that there are parts there not shown in the book?