125-200cc Im nuts!

Well out if total boredom I decided to pull my Lectron off the WR250 and try the original Mikuni! Lectron has been pretty good but it was on the bike when i bought it and i just couldnt resist trying the original TMXx. Always felt the Lectron was a little flat coming off the bottom. Went from the original 3-1xl to a 3-2xl finally settling on the 3-2m rod.
Lanky Doug provided me with jetting specs to run Mikuni got all parts and carb is installed. Ready to try it but weather has turned for the worse. 14 degrees here right now not expected to gdt above freezing for a full week. Just want to see how good i can make bike run with original carb. Pretty sure I will go back to Lectron but figured why not try it??

I tried the Lectron (s) and found the same - was not a fan of the power delivery as I felt I was trading horsepower for a linear delivery. After researching it on Google and YouTube, it became readily apparent that the strength of the Lectron is the staid relationship between the low-end circuit and the mid-range circuit and how it leverages that relationship to deliver fuel. Guys have been impressed with it’s ability to run in large altitude deltas with minimal or no changes to the fuel rod setting which I believe attests to the aforementioned - it is not delivering the ultimate ratio to the conditions like an EFI but it is delivering a global setting for a multitude of conditions.

I traded in the Lectron for a JD Jetting Kit and was totally happy as I too enjoy the low end punch of a Mikuni. Just had RB Designs work his magic on the carb and now I can lug down low all day long with immediate response, no bog. Check out a couple of guys on YouTube running his mod and you will see what I mean. There is absolutely no hesitation hopping over logs and going from chugging to wide open.

In my opinion, for half the investment of a Lectron, I have a substantially better performing motor than a Lectron will ever deliver. Will it perform better than a Lectron when changing altitudes 3000’ at a time? No idea as my riding environment does not traverse extreme changes in elevation.

Hoping to achieve similar results. Thanks for the feedback

Thanks for the info Caferacer. Was readig up on the RB mods. If i decide to stay the course wit the Mikuni I may get the slide mod done first. Read a lot of good things about it.

I can vouch for the RB modded tmx. I have one on my 144 and it works wway better than I expected

In the same vein, I thought this thread from Thumpertalk was somewhat insightful.

https://thumpertalk.com/forums/topi...8-01-08-+Lectron+Review+2016+yz250&trlv=63906

Just spend the money and get the whole mod package. You won't regret it.

The guy's a nut, but he knows what he's doing and it really does work.

Update: 50 degrees here finally. Woods clogged with snow and ice but roads mostly melted. Fired on second kick. Had to adjust idle speed up a little. Revs much quicker in neutral sounds real snappy. Couple short runs up and down street feels noticably stronger off bottom. Couldnt really wind it out due to sand and ice still on street. Initial impression is good!

Finally git to really test Mikuni yesterday. 45 degrees all snow melted. Bike is quite a bit stronger off bottom. Lifts front wheel much easier just cracking throttle. Very slight bog when you go full throttle but then explodes nicely on top. Thinking i need to lower clip from position 3-4 maybe a tad lean in mid. No ping at part throttle using pump 93 and Torco race concentrate. Overall im very pleased. May sell Lectron and get the RB mods done to Mikuni??? Going to run Lacey/Forked River on Sunday for real test.

If it's a 36mm Lectron I'm interested if you decide to sell it

Ran 50 miles of wet icy muddy singletrac today. The Mikuni performed very well. Very slight bog when i crack it wide open maybe need to lower clip 1 position seems like a lean midrange condition. Bottom end is quite a bit stronger. Was able to run my 14/50 gearing in the tight stuff no problem. I think im gonna stay with the Mikuni. Started easy and idled good all day. Prob gonna send carb to RB Designs and get the divider and slide mod done. Read lots of good reports on this mod.

I found the Mikuni to be very responsive to changes and very precise. This is a good thing if you like tuning to get the most out of it even when there is slight changes in air density altitude... the bad news is it's sensitive to slight changes in air density altitude. I thought about getting different slides cut, thinking it might make it a little more forgiving when it makes the transition from the pilot to the needle. I just wasn't willing to spend that much on carb parts. The 1/2 step washer on the needle clip helped by allowing to go 1/2 steps on needle clip changes. (most carbs would not notice a 1/2 step but the Mikuni did). If you do send it to RB I will be anxious to hear the review, I was torn between the Lectron and RB and went with the Lectron. If you get the RB mods you will have done both and would know first hand the difference.

Ive got a RB designs blade modded 39mm carb on the shelf from my Wr 125 days - I cant say I really felt a huge difference .

Another Mikuni guy here. I have run a Keihin (with JD Jetting kit) and a SmartCarb on my 150 but couldn't tune either carb to the point I was totally happy. I wound up putting the Mikuni back on with the Suzuki needle and RB slide mod and am very pleased. It idles very nice, refuses to bog and pulls very hard through the mid range.

Bike us running really strong now. 1 kick starts good idle and clean crisp lugging power. lowered float levet to 7.5 mm and installed 30=pilot. air screw at 1.5 turns. GAY needle in middle slot with 430 main. The 30 pilot completely cleared up the 1/8 throttle sputter. Picked up a Thunder Products Torque Wing to try out next.

Good to hear you're getting it fine tuned to your local air.