125-200cc LECTRON....FOR SALE

Guys,

I will be posting in the Classifieds as well but since the Lectron from Kelly seems to be so popular on this list, I thought I would reach out directly and see if someone is interested in taking a brand new 38mm Lectron with cable and adjusting tool off my hands. Never had a drop of gas in the bowl - carb does not fit my application and I want to get it off my work bench as it is a very expensive paper weight. Paid north of $400 and hoping to get $345? Make me an offer.

Thanks -

"carb does not fit my application "

What is the application ?

Flat Track racing.

For what engine? 2 or 4 stroke applications?

My apologies for confusing everybody with the term "application." Perhaps the following summary will address the inquiries and PMs (thank you btw.)

My son campaigns a 2012 Husky CR144 that has been ported (thanks Walt) and runs a Scalvini pipe (if you have not purchased a Scalvini from list member John, you should - the pipe is nothing short of amazing and John is an absolutely great guy to work with.) Albeit I am on the bottom rung of the mechanic ladder, I felt that I had the bike dialed in relatively well by relying heavily on the aid of the forum and as a result, my son was doing quite well in the Open B Class in flat track racing. He turned 14 this year and was leveraging a Husky CR144 to compete against the 450's and ultimately finished the season First In State. Noting all the rave reviews of the Lectron, I ordered a brand new 36mm Lectron midway through the season and immediately noted that it drastically changes the power curve from "give me a cape because I look like Superman when this thing hits" to a more predictable, linear power curve with a bigger bottom end. My son relied on that original "snap" to compete with the four-stroke 450s and because the Lectron gives you the same predictable power as a four stroke, he finished at the end of the pack his first race out with the Lectron. I attempted to leverage the musings of the list and read all the Lectron publications I could find and ultimately, per the advice of the Lectron manual, I took it to a Dyno run by a Lectron tuner and spent a zillion dollars of dyno time only to discover it was going to perform as it was intended. I reached out to Kelly with the dyno charts and he hooked me up with the Lectron factory whereby they willing replaced the 36mm with a 38mm at no additional cost - great customer service and they are more than willing to work with you but ultimately, I have the wrong "application." I believe this is a great carb to provide a predictable and linear power curve with a noted bigger umph down low (I have the dyno runs to confirm) and referencing the collective rantings of the list, I guess you do not have to re-jet for big altitude changes (although that baffles me since the Lectron has a low and medium tune via the metering rod girth and length and a power jet for top therefore I do not get the 'no circuits' claim.) Hence, I have the wrong "application" as I was looking for "hit you in the face with a baseball bat" top end, RFN horsepower and I re-jet but twice per year as I live in the upper Midwest at a 900 foot elevation. The air changes twice per year - summer flat track racing and winter ice racing.

Hope that diatribe explains why I have a brand new, in the box, Lectron 38mm ready for your consumption at a discounted rate. Between the $400 for the carb and another $400 for the dyno time, I am hoping to recoup less than half of my investment.

Ok thanks. Good luck with sale.

Id expect that a 38mm lectron would give more hp than the 36mm though .

Did you do any dyno tuning with the mikuni?. Hp figures ? Just wondering what jetting its running

I rode a WR300 with a Lectron installed. Not my cup of tea. I'm sure they're wonderful for many but just didn't turn my crank. I like non-linear power delivery some I guess. You're not alone.

Can we see the dyno runs? This is a good discussion

Hoping to get the Mikuni up on the same dyno soon - would like to put the 38mm on there as well but then it would not be "new". Would be great to compare all three but that would prove to be another $400 out of pocket.

These graphs are about the only way to present what an engine is actually doing at different RPMs in a way that aids tuning if nothing else... It's sort of an inside look at engine performance written out on paper... Without it, its back to the seat of pants method ... Which has its place in tuning also ...

dyno graph below was my 150xc with the crap stock needle and slide and a miss aligned powervalve spline - jetting specs are at the bottom of the graph.
Now with the RM needle and larger main much better. The only thing I've noticed that is an issue with the RM needles and the other slides is you need a leaner pilot jet, the problem with this is the engine does lose some of its low down lugging power.
I've dropped from a 37.5 pilot gradually down to a 30 pilot and each drop gave a nice crisp low end but its been to the expense of pulling/lugging power. seems these engines like a fair load of fuel from the pilot.

As you can see in that graph the af ratio when its running along the horizontal line is perfect but that stock needle leans out massively as the PV opens.
Never managed to get the bike back on the dyno with the RM needle set up

If you were looking for peak HP you should have never bought a 36mm to replace a 38mm. I would like to see the dyno numbers comparing a 38mm Lectron with a 38mm Mikuni. I tuned on my Mikuni and had it dialed to the point that every change I made was a step backwards. When I put the Lectron it took about 3 adjustments and it was outperforming the Mikuni in every way including top end. Fuel mileage and easy starting was an added bonus but I will say that running wide open the mileage is not much better, it's when you're in the midrange in the tight stuff where the Lectron really saves the fuel.

My YZ125 has a Mikuni that works so good I feel no need to buy a Lectron even though I think it would get a small gain it's not worth the change to me. On the other hand my Mikuni equipped Husky WR250 was kind of a pain in the ass by being way too finicky when the relative altitude changed and benefited greatly from the swap.

I'll give my opinion on dyno numbers, mostly because I like to hear it but you can take it for what it's worth. After 25+ years of being a mechanic and involved in various forms of racing. We are not racing dyno sheets. What works on a dyno doesn't always put the power to the ground and many times will send tuners down the wrong path looking for peak HP when the number that usually matters more is how hard can you come out of a corner or off a drag race starting line in the mid range and put down usable power. If you think about it you are only at peak HP for the moment before you shift or the end of a straightaway in high gear which is probably less than 20% of the time. If you tune to the 20% at the sacrifice of the 80% You will have impressive paper dyno sheets to brag about and zero money winnings in your pocket or trophies (if your racing for trophies).

BTW one of the best 125 2t flat track engines was the 1998-2001 RM125s because they had a long rod and had more dwell time at TDC to make more torque. Long rod engines will make more midrange right as you come out of a corner getting a jump on the drag race to the next corner. I have never looked up the specs but I suspect that the Husky 125 is similar to the older RMs when it comes to rod length, bore and stroke. Most of the Jap bikes have since gone to shorter components to make the cyl shorter and the engine lighter so it will rev quicker but it comes at the cost of side loading the piston more and loss of piston dwell time.

He tried it back to back and it didnt put the "power to the ground" for him. Fair enough, I just wanted too see what the power curve looked like.

I wasn't trying to be argumentative toward anyone, in fact would like to see the dyno numbers especially a 38mm to a 38mm on the same day with the same relative altitude.


A dyno run can be helpful especially in a case like Watky where it shows a lean transition right as it comes on the pipe @8,000 rpm. In his case addressing that drop off would likely make his bike more powerful and easier to ride.

A KTM engine 125/150 engine uses a 110mm rod which is the longest used in that CC range. I've used one in place of a 104mm Honda rod.

He is down 5hp from what I would guess a model bike should make. Correction factor takes in altitude and temp changes to make a number that is comparable to other dynos.

My peak power could have been effected by the miss aligned pv shaft.

Get you a divider installed in the Tmxx carb. You will fool it to think it is a smaller carb and pick up more low end.
When you use the RM needle, you have to go up on the slide, generally a 5 slide to add more air versus Rich needle.
I went beyond the Rm needle and made my own so it delivered even more fuel. I ran a 6 slide and also ran the older 7 port cylinder, that I ported. We dragged bike against a stock Cr 150 and it passed it like it was sitting still. Also, best pipe was dynoport pipe, with the stock silencer.
I spent countless hours on that carb and it was worth it. I still kept the carb. Just in case I pick up another 144 or 150.
Oh, not all Tmxx carbs are alike! Find you a true blue 04 RM 125 one and compare the insides.

Slide on left is 6.0 and my needle I made. Versus 6chy 16- 62 needle and 5.0 slide.