I have a Blaster that has a K&N, Toomey pipe, 310 main jet. I have been having problems with it. I will bring it riding and it will run good for like 2 hours or sometimes longer. Then i will be riding and it will start to sputter when i give it gas in like first and second but it will still get up to powerband. As I keep on riding it, it gets worse and worse until i can hold the throttle wide open and it just wont rev high at all in any gear and in neutral. This sounds like a jetting problem but im not sure if it is because it will run good for a while and then start running worse as I keep riding. The first time it happened i just put in a new spark plug and adjusted the air screw on the carb a little and it ran fine for like 4 hours and then did it again. The spark plug looks good and doesnt look like its fouled. I dont think its running to rich because there is not a lot of smoke coming out the exhaust. Could it be an air leak or some other type of problem?

 

A 310 main is waaaayy to high for an unported blasty, try going down to a 290 and see if that does the trick.

Smokin Joe

 

ok thanks should the needle clip position be on the third clip from the top cuz thats what i have it on but the stock setting is the second one from the top

 

my buddies got a 250 with a fmf, and reed spacer, wiseco .020 over, and someother stuff. make sure ure gas isnt bad, and that the carb might have a piece of junk in it.

 

a 250 main jet? ya the carb is spotless there is no dirt or anything in it because i have taken it apart so many times to check if that was the problem and while it was apart i just cleaned it anyways

 

A 310 main jet in not waaayyyy to big. I only have a pipe and removed air-box and at my elevation (1800) feet. When i called LRD they told me that the 310 was the right jet..Although i do not no what the problem is i just wanted to let u know that i don't think that the jeting is the problem

 

or it could just be the motor is getting to hot. i mean its a 2 stroke air cooled motor they get hot easy