Help me fix my blaster

Hey guys. We picked up a blaster at a steal of a deal many years ago. It was on the side of the road for $600. The guys daughter used to race it and they were selling it because they thought it was making a bad sound from the engine (turned out to just be exhaust pinging). Anyways we paid $400 for it when I was in 8th or 9th grade. This was in about 2005 and I put a ton of hours on it.

Before I moved out of my parents house it started to get annoying. It's obviously a go fast fourwheeler and I never had an issue before with doing nothing but open throttle or no throttle.

First gear is fine, second is usually fine, once you start hitting the hirgher gears it just bogs down and every now and then it will stop bogging towards the end of the gear, shift up and it might do the same thing in the gears above, it might not. It's intermittent and can even cause me to lose a race against a 250 utility fourwheeler.

I am looking to get this thing back in the field and have been wondering what it could be. I've cleaned the carb, changed the plug nothing. My cousin who was a blaster fanatic had me drill a few holes in the air box before the filter, nothing. Could this possibly be an ignition coil or something? One of the exhaust studs came out and was leaking by the pipe so I thought that would fix it, nothing.

Any input recommended. Note because it was raced anything unnecessary was removed. No lights, no kill switch (except the key), FMF pipe, oil mixer removed and done manually.


EDIT
I just ordered a used, non cut wiring harness to ditch all the cut wires to eliminate any shorts.

Might grab a carb rebuild kit and ignition coil to see if that fixes it. Might as well do a carb rebuild too

 

Being a 2-stroke it is probably ready for a top end.

 

Probably. Is that something I can do myself? I work on cars not fourwheelers

 

You can do it yourself. You don't even have to split the case if I remember right. New piston and rings and get the jug bored for the piston or get a new jug. Should be able to do the repair in a day or 2 if you have to wait for parts. If it kicks over easy its probably ready for one. You can also test compression but idk what it should be for a blaster. Might also be a good time to consider a big bore kit.

 

It was bore'd 20 over to be raced with. It kicks over fine and idles fine it basically just bogs down under load. Random Gears, random tmes

I think since I have 80% of the fourwheeler ripped apart I am going to strip it down, repaint the frame, work on the engine and repaint all the plastics

Might as well rebuild the carb, take the engine apart and see what's up.

I'd really like to get it all done and start riding again