QUOTE (suzukiray @ Jul 16 2009, 06:52 PM)
I am a drag racer & engine builder. Lectrons SUCK for part throttle applications. They are abruptly pretty much either ON or OFF. They have NO idle circuit or tunable midrange adjustment. Do yourself a favor if you want a carb that big & get a Mikuni 45. You will be MUCH happier with throttle response & drivability! Ray.[/b]
I seem to remember saying something about that when I was dyno-tuning a Lectron for a Honda. It came in as 440EX with a Lectron, and the owner didn't have the money to rebuld the same motor combo - it went to a stock-bore 400. I had to tune that Lectron on the dyno, for the smaller motor. It sucked, because I tune for all-around riding.
Kinda hard to tune a Lectron for that - all-around. Doesn't work too well, even on a dyno.
If you really think you need that size of carb, then look around at your options for that size. Mikuni HSR carbs are SUPER easy to tune.
But, you're not gonna listen, so it doesn't really matter. Go with your Lectron - your mind is already made up.
Just so you know, a Lectron for dirt is about the same thing as putting on an S&S carb on a Harley - it's just about a straight-bore carb, and good for one RPM. Straight-bore diameter, versus your engine displacement versus your RPM tells you where your carb size will perform. That's a drag racing thing, right there. One throttle position, only, as far as the carb performance goes.
RAY nailed it...