1st problem bike smokes like a trooper and bogs down at full throttle. Auto mixer is disconnected and fuel is mixed at 40:1. (i race motocross and used to run my bikes at 40:1 but have no clue if its right for a ATV)

There was a split in the air boot right by the carb and it had sucked a lot of dirt in which i have cleaned out the carb thoroughly and the piston, rings and cylinder are ok remarkably .

2nd problem is the engine wont turn over unless i directly connect the live wire to the red/white wire under the tank, starter motor is fine. This is the starter relay or is there any chance it could be another problem?

Where is the best place to order parts from in the UK?


I can do anything mechanical but electrical is a weak point

 

The start problem could be the start button. Other than the relay, it's the most common problem.
You did a compression test?