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Discussion Starter #1
I have an 05' 1100 w/BSR37 carbs. I got the bike from my brother who changed out the pipes and rejetted the carb. I pulled the plugs yesterday and found the rear jug burned nice & gray. The front plug was black and smelled like gas. I suspect the air/fuel mix needs to a adjusted. Any thoughts on what the problem is and how to fix it?

Thanks

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https://sites.google.com/site/vstar1100kb/home/tuning/carb-jettingscroll down to table A that will tell you how to jet your bike.are the pipes slipon or full performance,with only an exhaust change you normally up your main jets by putting the front jet in the rear carb and getting a size 115 and putting it in the front carb,stock setting on the mixture screw is 2 turns out. you could have a stuck float in the front.
 

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The rear cylinder and its carburetor sound OK. The front cylinder is running rich. Check its air filter, if the two carbs have separate filters. Check that the enrichener is operating correctly. If the bike has true dual exhausts with no crossover or connection between them, the exhaust for the front cylinder will be sootier than the rear cylinder's pipe. Once the easy stuff is checked, it is time to look into the carburetor. It could be jetted incorrectly (compare jet numbers to the jets in the rear carb bearing in mind that sometimes correct jetting differs between carbs) or, if you are lucky, a jet may not have been tightened correctly and may have fallen out. Float levels are also important, and depending on the setup it might be easy to check them with no more than a couple of short pieces of clear tube.
 

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Discussion Starter #4
carb adjustment

Thanks for the link, it was very helpful. There is a very well written description of jetting issues based on throttle opening. At this time the transition on the throttle feels pretty smooth, I'm not sure there are issues with the jetting or float being stuck. I ran stock dual pipes on the bike for a short time, the plugs burned pretty evenly. I have just built and installed a 2 in 1 exhaust and that is when I started noticing the front jug burning rich. Is there any way to lean out the carb mixture without re-jettting?

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Discussion Starter #6
Adjusting Carbs

Thanks Nick,

Is the PMS screw on the outside of the carb or will I need to pull the bottom off to get to it?

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