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Discussion Starter · #1 ·
So I installed a mod quad intake and cut up the airbox so it is open but blocked of where the exhaust is, at the same time i did the clear tube mod, installed #25 pilot jets and cut into the intake manifold to smooth it out.
in neutral it revs very quick but when i do a w.o.t run, the power seems to be less and it bogs down when i reach 3rd gear and starts backfiring. I'm running a dj kit and have the biggest recommended jets in it, any thoughts
 

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Your description is still quite vague, so without additional information, it's going to be a total guess in regards to anyone trying to get your jetting right. Stock or aftermarket exhaust? What is your current jetting? Any and all information is helpful.
 

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Discussion Starter · #3 ·
im running a full lrd exhaust and i believe im running 145 and 150 dj jets and on the middle clip (3rd i think) for the needles, and air/fuel screws are 2 1/2 turns out, and im at 2000 ft
 

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DJ jets go in sets of two below 150 - 140, 142, 144, 146, 148, 150 then they switch to intervals of 5 - 150, 155, 160 if I remember correctly. If you have a 145 you for sure don't have a DJ jet in the one carb as it is a mikuni number.

With mikuni jets you are likely wanting to be in the 160/165 or 165/170 range depending on altitude, porting, cam, piston.

If you simply want to verify that you are lean use a rubber band and plastic bag over part of your air filter and see if it runs better (which I'm sure you are lean)
 

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DJ jets go in sets of two below 150 - 140, 142, 144, 146, 148, 150 then they switch to intervals of 5 - 150, 155, 160 if I remember correctly. If you have a 145 you for sure don't have a DJ jet in the one carb as it is a mikuni number.

With mikuni jets you are likely wanting to be in the 160/165 or 165/170 range depending on altitude, porting, cam, piston.

If you simply want to verify that you are lean use a rubber band and plastic bag over part of your air filter and see if it runs better (which I'm sure you are lean)
I agree.................
 

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I agree also - AFIK, DJ jets don't come in odd numbers so you are using Mikuni's (which come in multiples of 5) and they're way too small...

If they ARE DJ's, you should try 146L/148R.
 

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Discussion Starter · #8 · (Edited)
thanks for the help, i must have mixed the jets up when putting them in
 

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Discussion Starter · #9 ·
so i replaced the jets with 146/148 and it dosent seem to be running lean but the carbs seem to run out of gas
 

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so i replaced the jets with 146/148 and it dosent seem to be running lean but the carbs seem to run out of gas
Before I go on a wild goose chase trying to help you, maybe tell me what you mean by "the carbs seem to run of ouf gas"................
 

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Before I go on a wild goose chase trying to help you, maybe tell me what you mean by "the carbs seem to run of ouf gas"................
Agreed - MUCH more detail on the symptoms, please - don't be afraid to write pages, if necessary... just helps us figure out what's going on.
 

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Discussion Starter · #12 · (Edited)
ok, so at idle when i rev it up it seems to run great meaning theres no backfireing no hesitation and puffs a little black smoke and smells VERY strong like burnt gas (more than usual) im assuming that means its running rich, now if im cruising at half throttle and gun it, it starts to pull then hesitates and starts backfiring,then clears up when i let off the throttle. when im decelerating it also backfires badly. it started doing this after installing #25 pilot jets, the clear tube mod and removing the airbox
sorry if my descriptions are bad, im not very good at communicating over computers. so hope this helps
 

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ok, so at idle when i rev it up it seems to run great meaning theres no backfireing no hesitation and puffs a little black smoke and smells VERY strong like burnt gas (more than usual) im assuming that means its running rich, now if im cruising at half throttle and gun it, it starts to pull then hesitates and starts backfiring,then clears up when i let off the throttle. when im decelerating it also backfires badly. it started doing this after installing #25 pilot jets, the clear tube mod and removing the airbox
sorry if my descriptions are bad, im not very good at communicating over computers. so hope this helps
Are you using aftermarket needles and if so, what position are they in, what size main jets........
 

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Discussion Starter · #14 ·
im using dynojet needles on the middle clip and dj jets which are 146/148
strange thing though i adjusted the air fuel screw out 4 turns and the symptoms cleared up and it runs fine
 

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thanks for the help, i must have mixed the jets up when putting them in
you will find that the mikuni main jets go up in series of 2.5 and the same for the pilots,standard 22.5 and upgrade would be 25,/standard main jets 140/ L /145R upgrade 142.5 L /and 147.5R. NOW i need help jetting for kn air filter/dg end can/air box lid on /standard carbs and jets
 

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Discussion Starter · #16 ·
are 4 turns out for the air/fuel mix screw too much or can i go more turns
 

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Discussion Starter · #18 ·
whats the next size up from a #25 pilot, i think its a 27 but not sure, thanks
 
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