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Need jetting help quickly!!!!

1166 Views 9 Replies 6 Participants Last post by  rupedawg
I'm headed for the dunes this Thursday. I have installed the K&N slip on and have put a 167.5 jet in it and still too lean. I assume it's too lean. Haven't checked the plug, but when a mash the gas, it has a nasty dead spot in it and acts like it runs out of gas until I back off of it. I guess my question it, does anyone know if I can just keep increasing jet size until it comes around, or is it necessary that I adjust the needle with the jet. I would like to just changes jets without messing with the needle, but if I have to, can someone tell me exactly how to adjust it. Any help would be appreciated. Thanks.
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My elevation is about 800' It falls on it's face at higher rpm's. I think I'll take your advice and just get a handful of jets. As long as not moving the needle doesn't hurt it.
J-man, I'm at 800 also. 160 main, 1/4 turn in (just for good measure on the low end)on the pilot screw. That's with the W/B all 8 "stock" discs, K&N drop-in, no foam pre-filter (say that cause some people are running them) and 5 Uni-vents. Haven't done an official jetting check, but the local racers (Rath and crew) are running this.
I run the WB pipe with all 8 discs...no quiet core...160 jet and with the K&N drop in with no prefilter and it runs fine. But with the K&N slip on that I just purchased it's getting more air and the 160 won't cut it, as well as the 167.5. Which one is the pilot screw and what does it do? I don't know much about carbs, this is my first experience.
The pilot screw is located under a brass plug on the bottom of the carb just in front of the float bowl. You can use a 1/8" drill bit. Start drilling the center of it, and probably before you're done drilling the plug will come out on the bit. Turning the screw in (only make 1/4 turn adj at a time) will richen your mixture, and turning it out will lean it. This only affects the idle-1/4 throttle range of your carb. Hope this helps.
I suggest you go down to your dealer PRONTO and order a moose/K&N jet kit, then when you get out to the dunes you can play with it.
Okay, I think I got it figured out. Here's my set-up. K&N slip on filter (RU 1770; thanks JJGI5150), 167.5 main jet; 42 pilot jet; needle clip on the furthest notch down from the top. I get no popping, it has awesome throttle response all the way through till the rev limiter kicks in. The only problem I may have, is it may try and load up if I let it idle for a long period of time. If that happens I may move the clip up one notch. Thanks for everyone's help!!

P.S. I'm taking my air box, K&N drop in filter and original 160 jet with me just in case it acts up, that way I can put it back to the way it was and continue on. Thanks again.
Okay now I have a question. After going through the whoops and stopping my friends noticed that there was a lot of gas coming outta the overflow tube from my bowl. im using a 167.5 main and a 50 pilot. I know that the main jet isnt too big because if i go any smaller it starts to cut out and that is what seems to work the best. Then another inccident that happened was while going up a hill really slowly it seemed like it just flooded out or bogged down and died even though i was in first gear. What is up with my crap. My plug looks okay still so i know its not running too rich.
Sounds like a float is stuck. I'm not a pro on these small carbs, but I had an old hotrod that was having those same problems. It was fine while I was running it hard, but when I tried driving slowly, the carburetor was "loading up" with fuel. It was a result of a float sticking and fuel was constantly running in and eventually flooding out. You need to check your carb and make sure there is no dirt inside that may be causing something to stay open. Also check to make sure you reassembled it correctly. Make sure nothing is upside down or missing. It's actually very easy to put something back in incorrectly. "attention to detail"
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