Hello.I have a Banshee-99 with FMF pipe and silencer.I want to change the carbs but in Spain are very expensive.Anyone know what is the response if I bore the carbs?What size?what pilot and main jet?Too,Id like to mill the cool head.Anyone make this before?How much can I mill,0.25,0.50,0.75 mm?
Thanks.

 

The carbs can easily be bored 2-4mm over and main will need to be richer by at least 4 sizes.than what you have inthere now and the pilot up as well,
Im not to sure on how much can be milled of the coolhead but you want to end up with about a .020" squish band,

 

you can oval bore the carbs(increase the height but not the width of the carb bore), this will help top end but will not kill the bottom end as if you straight bored them.

 

What kind of increases can I expect from oval boring? Jetting changes? Does anybody have dyno charts?

 

the jetting can be checked by using a EGT gauge. mark the throttle 1/4,1/2,3/4, and wide open. run the machine up a long hill at the different throttle setting and read the exhaust temps and rejet to suit. a good EGT meter with recall so you do not have to try to read it while you are riding costs about $300.00 so if you do not have one your best bet is to buy modified carbs that this work has been done to.