whats up guys I need help iv had nothing but bad luck with my yf....ok I bought it and it was runnin wicked lean, so i was tol to rejet and I did with teh dynojet stage 2 I also removed my air box lid, I was told that the dyno jet sucks and I still need to get a 45 pilot so I did, and I dont know if it did it before I rejetted cuz i was affird to drive it but when I hit teh gas hard and to the boards my quad dies and shuts off, this is a pain cuz i love to hit jumpa nd wheelie and it makes it kinda hard, the other day I gutted my stock pipe alittle and rejetted with what dyno jet told me to use for a higher flowing slip on and open air lid, and it does it still maybe even alittle wosre there is amore power but I cant stand the dead stop anymore! also witht eh kit I had to use a diff needle on the 5th clip and tune the air/fuel miture screw 2 1/2 turns......plz someone help me im gonin to an open track this weekend and I wanna be runnin good......thanx guys!!

 

plz guys anyone????

 

What did you do to it to cause it to run lean in the first place. Was it running that way when you brought it home? Other than re-jetting, have you done any other mods to it like remove the air box lid or new pipe or anything.

 

throw the damn dynojet kit out the window. Then go buy yourself a new needle and a 170 main.

 

Whatever it is that's causing your bike to do that, I have the same problem. When I accelerate hard and get to the top of 4th and 5th gear the bike coughs and misses bad. I really can't get any top end out of it. Some people say that it is the rev limiter but sometimes it just dies out just like you mentioned. I've got a full Curtis Sparks exhaust and K&N filter with no lid. I'm running a 4th clip position on a Curtis Sparks needle, 176 main, 45 pilot, approx 2.5 turns out on a Zip Ty fuel mixture screw. I've jetted up and down and up and the only reason I kept the 176 in is because that's what other guys that I've spoken to locally are running. I should have stayed stock, the bike ran much better.

 

Can't you just do plug tests like on a 2 stroke? Thats how I jetted all my bike and it works great.

 

yes I took air box lid off and gutted alittle out of my stock pipe.....it rean lean right from the store, my cousin and I bought ours at the same time and we both were runnin lean and I was told on here to rejet......its not lean anymore but has this problem, why do I need a new needle? cant I just run my factory one and just get rid of the dyno jet kit stevendsm? anymore help would be much apricated....thanx guys

 

You can run the stock needle with no problems. I ran mine on the 5th clip for a while. Thought id try the NCVQ needle cause everyone spoke so highly of it. If you have a dead spot in the midrange of throttle they say the needle clears this up. I didnt but the needle was cheap so I tried it.

 

IMO the dyno jet kits are junk. That's what i had and i took them out and threw them away. My mods are cam, no lid and no spark arrester. My jetting is 165 main 48 pilot and i am still using the stock needle on the 5th clip. It's hard to tell if there is something wrong because you are using dyno jet. What size dj jet did you put in?

 

42...I just had my brother pick me up a 170 main and im gonna ut my stock needle in, or do you thin I can still use the dj needle. with my lid off no spark arrestor, a few holes drilled in the pipe, 45 pilot, 170 main what should I put the clip on the stock needel if I cant use the dj one and what should I set my air set screw to its at 2 1/2 rigth now....my elevation is from 800-1500.....depends on where I ride, thanx guys!