KX Riders

Maintenance & Technical => KX250 / KX125 => Topic started by: RoostDaddy on February 22, 2009, 11:33:30 AM

Title: Big carb
Post by: RoostDaddy on February 22, 2009, 11:33:30 AM
I know many guys running the 500's (including myself) are using 44mm lectron carbs.  Anyone know how big of a carb you can run on a big bore 250.  I've run a 40.5 keihin, but thinking about either a 41.5 Mikuni or 42mm lectron for more top end.  Any thoughts?
Title: Re: Big carb
Post by: tobys 2 strokes on February 22, 2009, 01:50:30 PM
My ILR 330 has a 40 Lectron on it know. I had it dynoed with a 44 Lectron and it did considerably better but I havent had the extra funds to shell out for one as of yet.The bigger you go they tend to be a top end engine but with mine thats what I am shooting for I am running billet locked P/Vs.
Title: Re: Big carb
Post by: DoldGuy on February 23, 2009, 11:43:54 AM
what mods are done to the bike (285 / 310?) Is this a bottom- mid or mid-topend motor? If you have a 44 tron already, try that on there (will be a bit fat down low, but should be in the ballpark in the mid & top with current needle used on the K5). You should see a considerable difference in upper mid & top. Let us know how it works out.
Title: Re: Big carb
Post by: kaw rider on November 28, 2009, 05:51:10 AM
It depends on your build, you could run up to a 46mm carb.
Title: Re: Big carb
Post by: GREENKAW24 on November 28, 2009, 06:50:16 AM
I know many guys running the 500's (including myself) are using 44mm lectron carbs.  Anyone know how big of a carb you can run on a big bore 250.  I've run a 40.5 keihin, but thinking about either a 41.5 Mikuni or 42mm lectron for more top end.  Any thoughts?

I've seen guys at the hillclimbs out here run 44 lectrons on their KX250's, they're fast on a straight run but very doggy when the throttle is chopped/landing off big jumps/on breakers where they have to holeshot again into a steep hill.  If I was drag racing I would try it, why not?