Got Yamaha GT-80 and need some help!

[MuleWrangler]

I just got a Yamaha GT-80 in good condition (except it was a yellow-clay dirty mess) but am having some issues I need help with. I have ordered a manual but it is not here yet. :(

My questions:

1) What oil/fluid do I put in the gearbox (filler by the kickstart)? I did a search and saw someone said 10W40, but I am not sure about that.

2) What oil do I use in the oiler tank (that mixes with the gas)?

3) What is the shift pattern on this little guy? A search shows four down and neutral is up? I can't figure it out due to the below issue...

4) The rear wheel keeps locking--I put it into neutral (as far as I can tell) and start to roll it, the gear shift clicks and the rear wheel locks up. The gearbox fluid is very low--could this be the issue? It also does not seem to shift into all of the gears.

Thank you so much in advance!

 

[Gambini]

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.

 

[mitch_893]

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

 

[mitch_893]

[could you take a look at my post?