well i would like to start off by saying this is a great forum and very helpful with all the information you can find here.

well a friend gave me a i guess a 2007 tomberlin crossfire 150r. when i got it it wouldn't start. replaced starter then wouldn't start. replaced ignition coil with a
spare coil i had ( i know this probably isn't good but it works ) off of my drag car.
a msd blaster 2 coil. gave the air filter a shot of starting fluid and it started. then cleaned the carb. well after this i know why it was given to me. it would after an hour of riding burn a 1/2 a quart of oil . so ordered a 170cc big bore kit and some 10g weights its working good now but still want more power. so what else would you guy recommend from mods for this motor to replacing motor. if i change the motor i don't want to mod the frame too much and would like to keep a reverse on the buggy. thanks for any and all suggestions

did you put a cam in it, what type of exhaust are you running, what carb is on it now?

Know anyone who can port cylinder heads? That, a good exhaust and a good cam would be great.

Seriously, head porting can unlock MEAN HP if you know what you're doing.

stock cam and stock head. no porting done on it. also stock exhaust.

you can put a 4 valve head on.They are big money tho and its a job.You may still want to port and polish it.To me its been worth it.

you will need to get rid of the stock exhaust so it can breath, I am assuming you have a uni or k&n air filter what size jet is in the carb?

nope no uni just stock air box and stock exhaust. so i jets are almost stock

you need to get rid of the stock air box and rejet the carb. I am surprized it running good with the stock stuff still on it. running the stock jet will make it run to lean with that 170 kit . open up or replace the exhaust to

Either a 4 valve or stroker crank. I have'nt needed more than half throtle to pull a hill yet I typically gain speed on a hill with throtle, dont need it for the climb Funnyman is the same

ok just playing around i made a custom exhaust. its just 1 1/4" straight pipe.
i replaced the exhaust flange with one i found off of a 90cc 4 wheeler. it is about 3/4" to 1" opening and welded to straight pipe. man it is loud but haven't got to test the cart out much but it seems like its got a little more power. re-jetted carb a little but need to fine tune it.