lectron flatside carburetor...

[Chang-kuao-lo]

had an XT600 that i did a rebuild on been sitting for the last 5 years. did the top and bottom with 10.5:1 piston, bearings, seals, crank, the works. i knew that the stock carburetor wasn't going to cut it what with the increase in compression and rebuild items for the stock units are rare and expensive, so i got a shiny new set of keihin fcr that were supposedly "bolt-on" to the xt. first, the bottomside of the tank neede a bit knocked in to accomodate the throttle cable assembly, and i couldn't get any proper filtration to fit on them. and the damn thing wouldn't run on them, seemed like they were set up way too rich and i wasn't looking forward to going down the re-jetting road being that the things were a huge pia to remove/install. then the rob zombie 350 came along (the one i really wanted for many moons) and i gave up on the XT.

i had this old pair of lectron flatsides that i almost forgot about that i scored on flea-bay a while back for cheap. never did get around to trying them until the other day. they were a bit of an unfamiliar product to me, and i was a bit leery of them i guess.

so the XT sat under a cover rain, shine, or snow for the last five years. pulled her in, changed the oil and filter, flushed out the tank, new battery and threw the lectrons on. and didn't it start on the third kick. the throttle response with these things is phenomenal, just about had it go sideways out from under me a couple times at barely 1/4 throttle (having knobbies on pavement didn't help).

i'm pretty impressed with these lectron units. they are very short, which is nice when you have a lot of engine crammed into a relatively small frame. no needle and jets to piss around with, all done with a "metering rod" which is adjustable and interchangeable. and you dont have to remove the float bowl, or even the carburetor to do adjustments. just take the top cover off and pull the slide out. adjust the rod height for idle ratio, and change rods for top-end ratio. a one hour to 90 minute jet change winds up down to all of about ten or fifteen minutes.

High Performance Carburetors and Parts | Lectron Fuel Systems

all that's left is just to sort out the push-pull cable mounts (the one the carb came with was pretty flimsy and half worn out).

 

[scott84]

How do you like it so far? I'm thinking about one of these for my Suzuki DR370.

 

[Chang-kuao-lo]

took it for its first proper run yesterday. it seems a little finicky to get a stable idle out of it, but the mid to top end is great, explosive even. mind you the engine is not properly run-in, so i can't rev over 4,000 yet. but it wants to do a bit of wheelie stand in third gear if i crack it real quick (keep in mind i am running 10.5:1 compression). i'm thinking that the metering rods might be a bit bunged up (the carb is probably ~20+ years old), so i might replace them and see if i can get a better idle out of the thing. a while back i talked to the good folks at Fast By Gast - High Performance Motorcycle Parts and they told me to expect to have it run a bit on the rich side from idle to low speed, and that it will increase the idle speed to ~1,500 to 1,800 rpm.

it does have a bit of hesitation when going from off to on throttle (i'm not sure yet if this is a tuning issue, or just the nature of these units), but it does seem happier the wider it's opened. if you're doing a lot of wot on your DR, i suspect you might be real happy with the lectron. if you're doing a lot of low-and-slow type riding, maybe not so much. but i haven't got this thing properly tuned and run-in yet, so i would have to say the jury is still out.

your best bet might be to fill out the spec form at http://www.lectronfuelsystems.com/docs/Carburetor Specification Form.pdf and they should be able to set one up for what you want to do. i really like them just for the ease of tuning, small size, and simplicity of design.


edit:
just got off the phone with lectron, turns out it may be that i'm running a bit on the lean side at idle which causes idle and low-end stability issues. "the biggest problem people have with these is that they tend to over-think it, these carbs are really simple". nice folks, and they seem to put good support behnd their product.