So here are my suggestions on the bt80 in no particular order.
Upgrade all of the electrical connections because they will rattle loose and cause a huge headache.
The clutch is a wet centrifugal clutch. There is lots of confusion information, it took me a while but I found out it is in fact wet.
40 chain is almost too wide for the engine side.
Most performance parts won't bolt on.
You can't use any aftermarket mounts for this engine.
Replacing the stock air filter gives a massive boost in power.
The pull starter brakes easily.
Lights are awesome.
If you idle too long the fuel in the float bowl will start to boil and the engine will die.
There is probably more I'm forgetting, pm me if you have any specific questions
