hey all, im new to the forum but i just picked up an 89 blaster real cheap and just wanted to get it going for something else to putt around on and so i had the top end bored and a new piston, rings, complete gasket set, pro circuit pipe, boyeson reeds, and an oil injection block off kit put on as well as a new spark plug. I mixed my fuel at 32/1 with spectro 2 stroke oil. well problem is i start it up and it runs ok till it warms up and then it just keeps getting a higher and higher idle untill its screamin! It doesnt want to idle down well at all unless i pull the choke out all the way and then it will idle down and then i push it back in and it revvs up unless its cold and i checked the carb slide and it doesnt move! well my first thought was air leak, so i put a leak down tester on it adn it held 20 lbs for like 15 minutes easy so next i thought carb, i tore it down cleaned it and everything and its got a 240 main and stock pilot and 2 1/2 turns out on the air screw. is there something im missing???? Thanks for any help!
blaster revving too high after rebuild
- Thread starter blazin450
- Start date
you are jetted way too low you should be more like 300 with those mods. I would buy like 270-310 jets and start high and work your way down. you are running way lean is why it is going crazy. also only put like 7 pounds of pressure for the leakdown or you could blow your crank seals out.
Woo hoo 1001 posts. sh*t i have no life outside of this place lol. probably because i am STILL buyin parts for my build. sorry for the tread jack
i dont think the main has anything to do with idle anit that the pilot thought main jet was for WOT i think hes got a air leak
Well i did have an air leak around the intake boot after using the leak down tester so i took out the gaskets and rtvd the crap outa it let it sit a day and did the leak down again then it held air no prob. Fired it up ran great then i put it in neutral revved it up and it took forever to idle back down. Messed with the air screw the idle screw everything. Idles great as long as i dont give it gas. Im pretty lost. Also crank seals r brand new! Thanks
stock pilot should be just fine. i am having a hard time beliving that pro circut pipes only wants you to go up one jet size from stock. does your throttle cable feel like it is sticking at all. I really think i would up that main jet. most people go to like a 260-270 just by taking the airbox lid off. either that or you have an airleak, but you swear you don't so, i don't know unless the leak is in the carb somewhere. take the carb off and cover the top and one side with your hands and blow in the other side and see if air rushes out anywhere.
well i got back to the blaster today i tore down the carb again and cleaned the choke and took out all the jets. I looked at the pilot a little closer and it actually said its a 25! i also blew into the carb with everything covered and i only had air come out of one of the vent holes. So i ordered a 270 280 and 300 main jet and a 35 pilot so ill find out how that runs and see if it makes a difference! Thanks!
^Good plan.^ I was reading along on the thread, and figured I'd say that yup, that pilot jet was WAY too lean for your engine. I bet putting in a 35 pilot and starting with a 280 main will make your engine behave. One of 'my' Blasters (it's a neighbor's, but I've adopted it to make sure he takes care of it!
) runs an open airbox and an FMF pipe. We put in a 35 pilot with the airscrew 1.5 turns out, and a 260 main. You've got a Pro Circuit pipe, which I think flows even better than FMF, so I'd say your Blaster needs at least a 260 main to run properly...
Also, random thought...make sure the rubber 'O' ring under your carburetor cap is intact. If it is pinched, twisted out-of-place, or missing, you'll have a massive air leak up there that a leak-down tester won't catch, and the bike will run lean.
