Is the transmission fluid supposed to be in the middle of the sight glass on an 02 Pro? I know GG calls for 350cc in the 02 and 400cc in an 04. I'm not sure if 350cc would bring it in the middle of the sight window or not

I just got the bike an I can see fluid if I tip the bike toward the throttle side. I don't want to use it till I've checked everything over. I guess I could just drain and refill with 350cc's.

Just drain it and refill with fresh stuff. Volume is all that matters. The window is nothing more than a rough guide.

for some reason american gas gas site recommends 350cc and uk gas gas site recommends 400cc for the 02 pro. i,ve ran mine and my mates run theirs on 400cc but we do change often. probably every 4 weeks. have fun refilling cos the filler hole is tiny and it takes ages. i made a small funnel from the screw on nozzle of a mastic gun. some people use squeezy bottles.expect a fair bit of swarf on the magnetic gearbox drain plug. thats usual depending on how often you change oil

Yeah, they sure don't make filling it easy do they. And on an angle no less. But the Spanish always seemed to have their own ideas about things. I used to ride Ossa's back in the day and they had a lot of unusual engineering, loved them though ...uh oh, now I'm given away my age The Squeeze bottle seems like a good idea. American GG recommends GM transfer case fluid. At 400cc's does it show in your window when the bike is level?

Thanks again

At 400cc, the window will be covered...also at 350cc

Hey, it could be worse for filling. I had a Sherco and you had to lay it on it's side to fill through the same tiny hole

i had ossas too. yeah you can see oil through window. might be an idea to blow out gearbox breather pipe from time to time.

I used to use 370cc and could never see the oil in the window without leaning it over.