Hello again, I finally got a 1980 XS400SE. It has the third version of the BS34 carbs. I am trying to get the carbs as close to stock as possible as a baseline to begin jetting properly. I can't find any other info about the needle my carbs have, and was wondering if anyone can give me clues on this setup.
I have a 135 main, 42.5 pilot, 271 y-4 needle jet, and a 5gz15 needle on the 3rd clip from the top. The removable jet on the bottom left hole on the back of the carb says 155 on it. The fuel mixture screw is 3 turns out. I have K&N pod filters and stock exhaust.
I am also wondering which needle clip is considered #1. is it the top groove or the bottom?
With these filters should I drill out the plugs to adjust the air screws?
Any info on how close this is to stock, and how this needle compares to stock, will be appreciated very much.
Thanks
Lars
I guess that it wouldn't hurt to add a little intro, it has been a long time since my first.
I am a Mechanical engineering technology student at Camosun college in Victoria BC, Canada. I just about bought this bike almost a year ago, but couldn't get the money together. My plan is to build it into a little two person bobber, just with a longer seat than a normal bobber, like the seats on the 70's trail bikes. For a final project at school I am considering changing it to full electronic controls for the throttle, clutch and shifter. That sure could give it a clean look, no cables, everything inside the handlebars.
Anyway, I have spend a lot of time lurking on here, now I am looking forward to being a more active participant.
I have a 135 main, 42.5 pilot, 271 y-4 needle jet, and a 5gz15 needle on the 3rd clip from the top. The removable jet on the bottom left hole on the back of the carb says 155 on it. The fuel mixture screw is 3 turns out. I have K&N pod filters and stock exhaust.
I am also wondering which needle clip is considered #1. is it the top groove or the bottom?
With these filters should I drill out the plugs to adjust the air screws?
Any info on how close this is to stock, and how this needle compares to stock, will be appreciated very much.
Thanks
Lars
I guess that it wouldn't hurt to add a little intro, it has been a long time since my first.
I am a Mechanical engineering technology student at Camosun college in Victoria BC, Canada. I just about bought this bike almost a year ago, but couldn't get the money together. My plan is to build it into a little two person bobber, just with a longer seat than a normal bobber, like the seats on the 70's trail bikes. For a final project at school I am considering changing it to full electronic controls for the throttle, clutch and shifter. That sure could give it a clean look, no cables, everything inside the handlebars.
Anyway, I have spend a lot of time lurking on here, now I am looking forward to being a more active participant.
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