Got Yamaha GT-80 and need some help!

I have one GT80 as well, i can help, i guess.

1) the oil that the gearbox uses is a valvoline sae 20 or similar, it has no distribution, it´s just for the clutch and bearings, so, no matter if you can´t get that one, a +/- 10 would be fine.

2) in the automix tank you should use any quality 2t oil, motul, castrol, but be sure that you are using an 2t oil.

3) the shift pattern depends of which model do you have. the older models have 4 shifts so the pattern is neutral is down and four ups will shift between 1th and 4th. modern ones have 5 shifts, so the pattern is the usual in modern bikes, 1th down, neutral between 1th and 2th, and all the rest are up.

4) for unlocking the wheel (that´s neutral ;) ) you have to move the shift several times to the bottom, to be sure that you are in 1th and then, you have to move it a little up, it´s practice. Except that your bike is the older model, then you have to move it down.

Hope you´ll understand my poor english. Be sure that the automix instrument is working or mix the oil directly into the gas tank in %2 or %3. depending the oil.

i got problems too

i have a 1979 gt 80. it was running really good until one day it started backfiring and losing power. it got worse and worse until now when i start it and try to rev it bogs down and just makes a deeper sound. I've cleaned the air filter and Carby, changed spark plug, cleaned points. i don't know what else to do. The spark plug gets coverd in carbon really quick and after awhile it wont start until its been cleaned

[could you take a look at my post?