I have a 1986 trx 250r that has had a 330 big bore added to it. I was given a 38x40hv Lectron carb to use on it . Witch brings me to my question. Where do you find info on adjusting the carb? Where do yoy get parts? The only place that I could find on the web was racers edge and there site is now gone. thanks ----john

 

I think TC Racing still uses Lectron. the adjustment is simple. I Dont know the difference between your carb and the one I had. (I know they are though) But on mine the only adjustment you could make was by turning the rod that comes out of the slide in or out for rich or lean. The thing is there is only a certian amout you can go or you will mess the engine up. Any way I would call TC racing or FTZ.

 

Good advice to call TC or another good Lectron Dealer/motor builder. I believe Lectrons can only be purchased through certain dealers who know them well because they need to be "dialed in"" for a specific engine in order to work properly. Both my Lectrons are from him. He customizes these carbs(needles and taper)for your engine. But you should know all the details. Lectrons can be supplied with a variety of different length needles with different tapers and different grinds on the flats. Only someone who knows them and your engine can really dial them in. Get some pro help with it and it's a great carb. Slapping it on "as is" may not give you the results you want. Also you may need to modify your manifold to fit the Lectron properly.

If you want to try to adjust it ypourself to see where it gets you and ignore the above advice. Understand that the only adjustment is to the needle. The tapered needle which has a flat on it must always have the flat facing the engine. This needle is screwed into in a brass sleeve which "floats" against a spring. You will need a rubber faced set of pliers to turn the needle (or cover them with cloth). Screwing it in (counterclockwise) richens the mixture, and the reverse will lean it out. Before you go to adjusting the needle measure the length of the needle from the brass collar to the tip with a vernier caliper. It will probably be between 1.75" and 2.1" depending on which needle is being used. The short needle is normally set at 1.85", the long needle at 1.95" and the extra long needle at 2.1". These are the factory "mean settings" for each different length needle.
Try turning the needle 1/4 turn (moves up or down about .030" for each full turn). Then push the needle gently upwards into the slide. The brass collar into which the needle screws is spring loaded, and is "locked" when in the down position. When you push the assembly up you can rotoate both the neddle and the bushing together. Rotate the assembly so that the flat on the needle is facing the engine again, and put the slide back into the carb. If you cannot get the engine to run right by going up or down 8 quarter turns in each direction then this needle is probably wrong for your engine - assuming everything else is equal ie. in good repair.

 

The Lectron's are great carbs - got 2 on a banshee and the simplicity and ease of working on them by far puts them ahead, especially when rejetting needs to take place. I've been getting my parts for them from Fast by Gast (gaskets, main jets, needles, ect). Although they deal mainly with 2 wheelers, they have finally started getting stuff fab'd for the quads - I just got a new T cable to fit the 'shee from them.

Like all carb's, the needle on the Lectron is only good for the 1/4 to 3/4 throttle range, then the main jet(s) are the sole input. Depending on the carb you have, you can have 1 jet or 2 jets. The main jets are usually fed through tygon tubes from the bowl of the carb to the top by the slide housing (flat head screws have the main jets underneath). If you watch your carbs while accelerating you can see the fuel sucked up throught the tubes to the main jets.

When I got this 'shee, it was set up to run alcohol, and I am just running 117 octane racing fuel, so I had to change both my needles and my main jets - I've just about gotten it "right", but think I need to drop down 5 microns on my mains once the weather straightens out in the spring. It only takes about 5 minutes per carb to adjust the needle and/or change the main jets.

 

hckycoach:screwing the rod in richens it,unscrewing leans it(you said counterclockwise,but meant clockwise).And the carb he has, has another adjustment,the top end jet.TC refuses to talk about the power jet carbs,my guess is he feels that they are not needed.I love my lectrons,but have toasted twice on WOT,which I figured that the power jet would have saved me.By the way TC=814-723-3514 Chris Grissom of Suzuki of Paris Tenn. can help you w/Lectrons also

 

I also have a 38mm Lectron on my R. I have the power jet and it is good insurance for when you ride wide open a lot. A Mikuni pilot jet is used as a power jet. I think you can get them as big as #120.
I think I am running a 5-2 metering rod. I couldn't find on locally any larger than #90 so I drilled one out. It worked great for cold weather.
ERIC

 

LT 80 clockwise it is thank you.

But we have never has a problem with highend throttle response on our Taper Jet Lectrons - either of them. Both were dialed in by TC who built one of the engines with the Lectron, and worked on the other and so set up the carb for that engine.

Thats what I meant about having an engine builder set up the carb for the specific engine. The flat on the needle is your secondary jet.

There were QC problems over the years with this flat not being consistent from the manufacturer, so engine builders like Tom Carlson individually grind the needle to their own scale and finish. With all the time and effort TC has put in to perfect this setup it is little wonder why he won't talk about a Lectron Carb with a secondary power jet.

Without knowing the level and style of porting, valve size and grind, cam set up and cdi box it is very hard to make a good guess about which needle should be fitted to the carb. Anyone supplying a Taper Jet Lectron without knowing all this is running the risk of having problems like you are seeing. The Lectron with the secondary jet (I think called the Pro Jet) was their solution to the quality control problems mentioned above, and allowed them to market a successful product without being as dependant on engine builders to "dial in " their product.

 

I talked to Tom Carlson at RedBud last year about my carb and he said he didn't believe in using a power jet. Of course he is a big 4 stroke builder and I am running this on a 250R.
Try to contact Racers Edge at 1-(888)-558-7822 or 1-(901)-286-1688. Ask for Barry or Clint.
ERIC

 

Racers Edge still around? I havent been able to find anything on them, although I havent searched real hard. I done alittle business with them a few years back for the 250X I owned at the time and thats where I got my Lectron from. Barry and Clint were awsome guys and seemed to realy know their stuff. Anyway the X I had was built by Sparks. After awhile the Sparks pipe fell apart. The quad had the stock carb on it which is something I didnt understand. It may have been put on by the previous owner but anyway I know it had alot of work done to the engine. Porting, high comp. piston, no rev limit (or at least I never found it hee! hee!) pipe,ect. They set me up with a WB pipe and the Lectron carb. After a few runs it was tuned in. Ran better than ever! I never had a problem with the top end for the next few months I had the quad. I sold the X because the bottom end went south 2 times in a month!