Help please..


New Member
Feb 21, 2022
New to the site And it has been several years since I have worked on a blaster or banshee as in back in 2000 what's the last one I built.
Now what that said this is my situation. About 4 weeks ago a buddy of mine brought me a 1999 or 2000 blaster the quad would not Idle at all it had been setting out in the weather for a few years yours my buddy purchased the blaster paythe blaster paid an individual to do a top end on it on it and they never could get it to idle it would fall out plugs almost immediately. So in my wisdom and experience the 1st thing I did was pull the carburetor off political part clean it very well checked make sure the main and the pilot jet were correct and that the needle was in Is the correct position for a stock Top end. When we got it to fire up I heard a horrible rattle needless to say the quad needed a full rebuild rebuild. These are the parts that we have put on the quad now I fully rebuilt the motor with a wisco lower crank bearing and seal kit . And winstold a wisCO high compression 240 big boar kit with ported cylinder and don't top high compression piston If he really does not want to put exhaust on it he did put a k&n air filter on it. It has the force reads And the stock making M28 model carb. With 300 main jet needle needle on center clip and we started out with a 37.5 pilot jet . And before anybody throws it out there like I've said previously previously I've done big boars on 4 other blasters in the past using thusing the stock 28 mm carb and A290 to 300 main jet and a 37.5 to 40 pilot jet And I know somebody or several people are gonna say it needs a bigger carb But in the past I have built 4 other blasters big bore and they ran perfect. When we put it back together is together the 1st kick full choke it fired up and I started running the rev cycle to break in the rings After the engine got warm and cool I did the same thing again quad started up perfect with no choke, I ran a second heat cycle on it let it cool And then because it was slightly boggy I started adjusting the idle air screw I got it with the 37.5 pilot jet About a turning 3/4 out and the quad came alive Was beautiful and put it around the yard for about 5 minutes then it acted like it was Refusing to idle back down even with the the idol screw back off all the way I pulled the plug there was absolutely no carbon build-up no white on the plug no Brown no black on the plug. When I tried to start it up again the quad act like it flooded out Spark plug wet very wet is wet. So I dropped down to a 35 pilot jet and the quad would not run without my thumb on the throttle so I went up to a 40 pilot jet the quad would not idle at all If so now the quad has A290 main jet 40 pilot jet in it and it will still not idle one minute you fire it up and it'll run hot as Hades the next minute you'll fire it up virad up it runs cool as can be I checked for air lakes and vacuum lakes Could not find any the reeds look wonderful And well my buddy now has about $680 in parts in the squad and I'm trying not to burn up the top end Does anybody know what jets are recommended nowadays in the 240 big boar kids With the mccooney 28 mm carb
Sorry but I had to stop reading your post because there’s so many mistakes.

Yo hard to translate. Try proofreading it. If you’re in a foreign country say so and I’ll try again
OK short and sweet to it . Is 1999 blaster fresh wiseco crank in the lower end Is newburyn's and seals in the lower unit. Boysen reeds , wisco 240 bigboard kit with wisco 240 ported jug , k&n air filter , 28mm makuni carb with 300 main jet 37.5 pilot jet, needle center clip. Won't idle . I tried a 290 main jet and tried 35 and 40 pilot. I'm scared to go with a stock main or stock pilot because I only accomplished the 1st heat cycle to break in the rings on a fresh build
Quick, hide this from the grammar and spelling Nazis

Wiesco never produced a big bore cylinder. Piston yes, cylinder no.

One thing you didn’t mention is where the air screw is set at?
DO NOT change the main jet !! It has absolutely nothing to do with it idling.
MJ is only 3/4 to full throttle .

Did you do a leak down test? How many heat cycles have you done ?
OK The kit I bought was from weisco It came with all the gaskets all the bearings the crank the piston the rings intake , valve reads and a bored ported cylinder. I've had my air mixture screw with all the pilot jets anywhere from 1 turn out to 2 and 1/2 turns out, with using all the pilot jets mentioned before . I have done 3 heat cycles you could almost call it 4 by the time I'm done getting it warm to change and adjust dust my air screw for the swaps I've done on the pilot. And it seems like any of the jets I put in with with new spark plugs I get absolutely no carbon build-up on it whatever, not white, black or brown. Wet plug on #40jet slite bog during heat cycle, #37.5 jet ,dry plug very responsive throttle, but no idle , and #35 jet ran hot and slow to to pick up rpm to 1/2 throttle
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Reclean the carb. The air passage from the air horn to the throttle bore is plugged. Make sure you can blow air through the passage. Also make sure that the holes on the side of the emulsion tube/ main jet holder are open. Remove main jet and slide and push it up into the throttle bore