Setting up my Lectron on my newly built WR300. I'm a little confused. I put the idle screw at 1 turn out from fully in. So I screw it in (clockwise) till it stops, then back it out (counter clockwise) one full turn. It idles high, but has crisp response to throttle input off idle. However, turning the idle screw out (counter clockwise) lowers the idle. What is that an indication of? If it idles high at one turn out of the idle screw, I should be progressively increasing the richness of the rod until idle comes back down, right? Also on page one of this thread Kelley's edit says to go by slide height instead of idle screw. But how is he measuring the slide height? Is he talking about the gap between the bottom of the carb and the bottom of the slide?
Its a idle screw You set it for the best idle as per any carb, Once the bike idles nicely you may have to fine tune the rod if its rich or lean but the norm would be it comes set around 1/2 turn to rich. Pretty sure if I turned mine in to one turn out every bike would sound like a weed whacker on full chat.
Call Lectron they will have you setup in minutes, this thread seems to be all about selling. They know the carbs better than anyone here.
Right your idle screw is a simple screw that has a point on that when you screw in pushes the slide up. That's how your idle is metred so winding your idle screw fully in with the throttle shut could just be biting into the side of your slide. Crack the throttle slightly and wind the screw in you should be able to get it to rev it's nuts off. Yes he is referring to the height of the slide that is allowing the air past. If your lean then your slide will be higher (I'm guessing that's what is ment)
Idle screw not that important jus set it wher it idles best 1 turn out normal tho. Juicy right jus lifts slide so crack throttle wen screwin in. Screwin in will increase revs as more air cumin thru
Okay, thanks all who answered. Shawbagga answered what I was really asking. Thanks for that. For some reason I was equating raising the slide with raising the metering rod. And that made me think it richens it. But now I realize that although raising the slide does raise the needle, there is more air coming along for the ride, too.
What Kelly was probably referring to is somewhere in Lectron's tuning info, says if slide is more than a certain distance up need to richen the rod. So if you need the idle screw less then @ 1/2 turn out the rod is lean. Both mine are 1 - 1 1/4 out.
I spoke to them last week, he stated it made no difference where the idle needle was set as long as you can obtain a solid idle. here are the notes he gave me on the 36mm setup. Lectron average settings Metering rod 2.020-2.095 Power valve 3/4 - 1 1/4 turns Idle screw not closed Top screws 6 - 32 X 1/2 inch
Yes, the lectron tuning instructions (PDF file from lectron) says "Note: with engine off observe the slide cutaway if the slide opening and very small it a good chance you are too lean. If the slide cutaway is open very wide you are most likely too rich." Problem with that is, it's touchy-feely. I'm a software engineer so unless there's a formula to use, or measurements to take, my brain goes nuts. But where I'm at with this is: It's a 38 mm carb. 1 3/4 turns out on the idle screw maintains a decent (but just slightly high) idle. If I go out even a 1/8 turn, the idle drops quite a bit and starts to wonder. Throttle response in neutral is crisp. When riding, bottom end is a little weaker than I'd like it, but transitions nicely to mid without a huge hit. Pretty nice. When getting close to the point I'd normally switch up a gear, like from 2nd to 3rd, if I maintain a steady speed and rpm the bike starts to ta-ta-ta-ta-ta-ta... Accelerate from there and it sounds normal. What's the ta-ta-ta...?
Stuttering? Most likely a little lean? Which rod are you using? Anyway, go 1/4 turn one way or the other (keep track!) and see what changes. I'd go 1/4 richer (clockwise) first, if it's worse 1/2 lean. My 300 likes the 3-1xl rod, so rich on top and lean on the bottom. After doing the tuning dance with the 300 I did the 165 differently. I set the idle screw and PJ to 1 turn out and adjusted/changed rods until it was good, then fine tuned a little with the screws.
Wish these carbs weren't as tall as they are. I have to take the dang tank off every time I need to get to the rod. It's a real pain. And for that matter, this is the hardest carb to get out of the boots. It's just way too long. And I believe its one of the shaved ones because it's only about a year old.
why do you need to get it out of the boots? are you not able to just loosen clamps and rotate to side to access the slide? im able to for my 360, even tho i know its older. 3 bolts and pop the fuel line..tanks off...seats off with a quick turn, pretty easy. better than having to remove carb to swap jets around. would have to hear the tatatatata you are talking about. it could be four stroking (too rich) or maybe lean. try adjusting richer and see if it gets worse or better. i wouldnt base the tuning off where the idle screw is at, unless the idle screw is way in or way out. tune the rod length for best performance then set the pj for best performance. try to enjoy the simplicity of the lectron.
thats why you take a minute and pop the tank, easier than pulling carb. seat and tank are super fast to take off.
Yeah, 250/300 is PITA compared to 165, but still worth doing. Once it's done shouldn't have to worry with it again.
When I bought my Lectron in 2012 it was longer. I was able to move it closer to the engine by using the intake from the pre 2009 WR 250. 2008 and earlier had the older Mikuni TMX that was a little longer so the intake was a little shorter. Luckily on my Beta I able to loosen and turn to left to tune.
I actually bought the older intake boot from halls. But the 38mm lectron won't fit in it. Might have got the wrong part, but I verified with halls before the purchase.