FCR 37, will it work?

hey guys new to this forum, i have a klx/drz-s and i want to swap out the carb for an FCR. i have a 37mm from a kx250f laying around not in use. just curious if anyone has done or knows anyone who was done this with a 37mm. i did search and could only find info was of someone asking if a 37 could be bored to a 39. my delema is do i use what i have and go into the swap blind or do i just scrap the idea and just buy the swap kit with the 39. i could car less about the possible loss of top end power with the smaller carb, all im after is to make it feel more like my mx bikes throttle response wise.  any help would be appreciated and thanks in advance.

im sure it would work fine, ive used smaller than average carbs on cars before, they have alot of response .. only thing is your likely on your own when it comes to jetting it and will have to work that out yourself .. it will likely take smaller jets than you'd think ..

yea i figured it would be different jetting. i will start off with the stock jetting for the kawi. i know the pilot will likely be lean but i know the main will be fat. just need to swap out leak jets. ill probably go with a 42 pilot, 55 leak and stick with the 172 main for now. would you happen to know if the tps will work properly? the plug in is the same,  i guess i could ohm it out to see if they are close. i know the plug ins are the same.

The FCR will certainly be better than the BSR, the FCR offers less venturi restriction (shaft/butterfly).  I'd ballpark your jetting from the 39 crowd and adjust from there.

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