banshee4587 Posted May 19, 2010 Report Share Posted May 19, 2010 hi i have a 2001 yamaha banshee with 392cc athena cylinders and pistons with 34mm mikuni flat side carbs cpi bigbore pipes and cant seem to get them to jet right.elevation about 1400feet. i have went from 280 jets to 400 jets and every time i put the jets in i test rode it and it does the same thing everytime. it starts first kick has 140 compresion on each cylinder. it starts off great no bogging but as soon as you hit the throttle it cuts out and has no power but never dies. if you hammer on it in first it hits the power band for just a second but as soon as you shift it just kind of bogs. i currently have 340 jets in it now and think its close to the right jets. anyone might have any suggestions on what i should do next? Quote Link to comment Share on other sites More sharing options...
firebanshee Posted May 19, 2010 Report Share Posted May 19, 2010 hi i have a 2001 yamaha banshee with 392cc athena cylinders and pistons with 34mm mikuni flat side carbs cpi bigbore pipes and cant seem to get them to jet right.elevation about 1400feet. i have went from 280 jets to 400 jets and every time i put the jets in i test rode it and it does the same thing everytime. it starts first kick has 140 compresion on each cylinder. it starts off great no bogging but as soon as you hit the throttle it cuts out and has no power but never dies. if you hammer on it in first it hits the power band for just a second but as soon as you shift it just kind of bogs. i currently have 340 jets in it now and think its close to the right jets. anyone might have any suggestions on what i should do next? It could be your spark plug caps(blown resistors)if you have the factory ones i would put new NGK ones on,are you sure your problem is jetting? If you pull the choke on does it make it better or worse?340s sound like you would be in the ball park.Are your carbs clean? Quote Link to comment Share on other sites More sharing options...
Fireroad Express Posted May 20, 2010 Report Share Posted May 20, 2010 hi i have a 2001 yamaha banshee with 392cc athena cylinders and pistons with 34mm mikuni flat side carbs cpi bigbore pipes and cant seem to get them to jet right.elevation about 1400feet. i have went from 280 jets to 400 jets and every time i put the jets in i test rode it and it does the same thing everytime. it starts first kick has 140 compresion on each cylinder. it starts off great no bogging but as soon as you hit the throttle it cuts out and has no power but never dies. if you hammer on it in first it hits the power band for just a second but as soon as you shift it just kind of bogs. i currently have 340 jets in it now and think its close to the right jets. anyone might have any suggestions on what i should do next? what needle jets and jet needles are you running. sounds like your way rich on your mid-range jeting. expect to jet down a bit on your mains. Quote Link to comment Share on other sites More sharing options...
youngracer281 Posted July 22, 2010 Report Share Posted July 22, 2010 what needle jets and jet needles are you running. sounds like your way rich on your mid-range jeting. expect to jet down a bit on your mains. Have you figured out what the problem was or the correct jetting? I am having the same problem. Please help. Quote Link to comment Share on other sites More sharing options...
Snopczynski Posted July 22, 2010 Report Share Posted July 22, 2010 hi i have a 2001 yamaha banshee with 392cc athena cylinders and pistons with 34mm mikuni flat side carbs cpi bigbore pipes and cant seem to get them to jet right.elevation about 1400feet. i have went from 280 jets to 400 jets and every time i put the jets in i test rode it and it does the same thing everytime. it starts first kick has 140 compresion on each cylinder. it starts off great no bogging but as soon as you hit the throttle it cuts out and has no power but never dies. if you hammer on it in first it hits the power band for just a second but as soon as you shift it just kind of bogs. i currently have 340 jets in it now and think its close to the right jets. anyone might have any suggestions on what i should do next? The carbs have to be baselined correctly to work. So they have to have close to the correct main jets, needles, clip positions, slide cutouts, nozzles, float height set, pilot jets, and a/f screw settings to begin the jetting process. Like the other guy said, if you have an ignition issue, or other runability problems, your gonna be chasing your tail. Quote Link to comment Share on other sites More sharing options...
T-rex Posted July 27, 2010 Report Share Posted July 27, 2010 I am selling a set of Gas 34mm Mikuni TM flat slides, I was running a 240mj, 40pj, needle in the third clip. Stock cylinder, 4mm crank, dune ported...bike ran strong 200ft above sea level. Hope this helps. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.