alright. i bought a 91 blaster that was non running for 400 bucks. wouldnt start. found out it needed a new top end, new crank, and new bearings. i tore it apart. replaced all the bearings and seals, put an 02 blaster crank in it. had the cylinder bored and put a brand new piston and rings in it. while i had it torn down i ported the head a little. didnt really port it but more like cleaned it up and smoothed it out a bit. i tore down the carb and put in a new gasket, main jet, pilot jet, and needle valve and valve seat. also replaced the o rings and the air screw. i cleaned it with carb cleaner and sprayed it out with an air compressor. then i got brand new boyesen reeds. the carb has a 230 main jet, i set the air screw like 2 turns out liek the manual sais, and the needle is on the 3rd notch. then i put it all back together and couldnt get it to start. foudn out my case wasnt sealed right. took i to a yamaha dealer and they ptu the cases back together with yamahabond and didnt have that problem anymore. if i put it in 2nd or 3rd gear and pull it behind another quad. it will pull for probably 10 minutes and then pop really loud and roar to life adn then die. then do the same thing prolly 3 or 4 times before it totally fouls out a plug and wont do anything. i have changed the plug about 3 times. i am getting a pretty strong blue spark. i have been using a champion plug. i then did a compression test and i have 153lbs of compression so i got some 93 octane fuel and mixed it 30:1 and i kicked it over atleast 30 or 40 times and i have gotten nothing. i pulled the plug out and it had a little fuel on it. not a ton but enough to make it damp. can someone please please please help me! give me some ideas or something. i have to be overlooking something. this thing has just been sitting and taking my money for about 6 months now!!!

 

This is probably a dumb question, but is your rotor keyed correctly? It can tighten down and feel like it's on right, but if not, it'll spin and you'll get a spark but not at the right time, causing "bangs" and poor starting. Essentially out of proper timing.

 

I can't answer your question, but I saw you were from Indiana so I thought I would say hello. I live in Kentucky across the river from Tell City, if you know where that is.