Blaster questions

[smokinwrench]

I just rebuilt the topend on a blaster Saturday. I also cleaned the carb. I rode it around for 20-30 minutes after I got it running. It ran good but a little rich on the top end. I gave it back to the owner, they rode it for a couple hours. He was riding back to his house, he said 3rd gear half throttle and it died. He pushed it home and said he couldn't get it started. THey installed a new plug and still wouldn't start.

I went and looked at it tonight and it started right up but sounds terrible and won't idle. It is making a bunch of noise through the intake. Not sure how to describe it other then there is a bunch of noise coming from the filter, seems like it has exhaust noise in the intake. Also the exhaust is so hot it is unreal just from a couple minutes of idling. I cleaned the carb, pilot and main jet were both clean, float is operating correctly with plenty of flow. The plug they removed looks good, dark brown color.

I would appreciate any helpful ideas. I'm wondering if the timing might have slipped some how.

[monster 84r]

broken reed petal? might as well check em.

[smokinwrench]

I also checked the reeds they are perfect.

[okieRrider]

i would check the timing on it....if it was retarded somehow it would cause it to come back through the exhaust.

[okieRrider]

lol my bad i meant intake

[Big D]

You have probably figured it out by now but to me it sounds like it was revved to the moon and something failed. When I rebuild a two stroke I will run it with premix and run the oil a little heavy for the first couple of tanks even if it still has the oil injector pump and a full oil tank it takes a little longer to break it in but I don’t like to do things twice. I would look at the flywheel key and see if it has sheared. If not then I would suspect possibly a broken piston skirt if you already checked the reeds. Jmo
I hope it is just an easy fix for ya.

[smokinwrench]

I think maybe it was abused also. The kid riding it normally rides a KX250, so I'm sure it wasn't riden easy. I haven't had a chance to look at it again.

[monster 84r]

that could be a problem. those blasters are great bikes but the kid might have ridden it like a watercooled, was it broken in while they were riding it?

did you put a wiseco piston in it or an oem? wiseco's arent too forgiving in air cooled motors.

[smokinwrench]

I finally got a chance to look at it again. It has a broken key on the fly wheel.

[Big D]

Glade you got it fixed for them