Lectron Carbs on a 450, anyone use these?

Finnigan

Over 1,000 Posts
Wanting to pull the trigger on a set of Lectron carbs, they claim jetless fuel delivery and no adjustments needed for temp/altitude. As someone who can never really dial in the jetting on my 1971 cb450 stock carbs, despite main and secondary swap and needle shimming, these sound too good to be true. On top of all that reviews say they give you better gas mileage. They are however, pricey as a brick of gold and I'm wondering if anyone on here can claim good results with them.
 
In place of a regular needle, needle jet and main jet a Lectron uses a special needle with different tapers to do the jetting.

I have a couple of pairs here and no intention of going mad trying to set them up. They are still popular with drag racers and there is a lot of information available for some applications but probably not for that bike. Check around and see if anyone used a pair on a similar bike to get a starting point and then start buying needles and a setting tool.
 
teazer said:
In place of a regular needle, needle jet and main jet a Lectron uses a special needle with different tapers to do the jetting.

I have a couple of pairs here and no intention of going mad trying to set them up. They are still popular with drag racers and there is a lot of information available for some applications but probably not for that bike. Check around and see if anyone used a pair on a similar bike to get a starting point and then start buying needles and a setting tool.

Should work good on the GT?
We both know they suck on a street four-stroke though ;)
 
err...Thanks for the encouragement, PJ...

I just got a notification they're sitting at my front door, so stay tuned for an update soon.
 
I wouldn't even try to use them on a 450 unless I had them and wanted the intellectual exercise, but for an all top end drag bike 2 or 4 stroke, for sure. But I already have a set of TM38s bored to 39.5mm for that :)
 
They remain fairly popular with 2 strokes. Power jets work very well for top end tuning on the 2t's.
 
I have seen them used in drag racing like teazer said, and did hear that they are a bitch to get right ..
 
A. The carbs are not idle synced, instructions said to put them on and run the bike, damn thing was WAY off right to left
B. Even though they were 'dyne tested' there was no gas in the lines or the bowls and nothing smelled of gas
C. The float levels are off, and not evenly off

So ya, money well spent
 
Keep going and let us know how they work. I'm interested in hearing about the throttle response in a street situation.
 
Lot's of people lust after Lectrons. Don't get discouraged right off the bat. And you can dyno test a carburetor without fuel, so that's not a good indicator of whether they had been tested or not.
 
Contacted Lectern for tech support (they are pretty good over the phone) and the float situation is fixed, now both headers read the same temps while the bike idles. The idle is still rough as hell but they encouraged me to take it for a short ride. I went down the block and was really pleased when I got on the throttle, it feels like a whole new bike and it sounds really nice. BUT i came to a stop and the bike died, it fired right back up again but I had to keep blipping the throttle to keep it alive, the ride back to the garage was the same story: amazing on the throttle and died when I came to a stop. I've had enough fumes for one day and decided to end on a high note since Lectern is currently closed, I'll contact them to figure the idle issue on Monday. In the mean time I couldn't help take a photo, they look pretty nice.
 

Attachments

  • IMG_0084.jpg
    IMG_0084.jpg
    2.4 MB · Views: 239
  • IMG_0085.jpg
    IMG_0085.jpg
    2.7 MB · Views: 188
  • IMG_0088.jpg
    IMG_0088.jpg
    2.9 MB · Views: 196
They look amazing and the throttle response is why people use them - that and the top end power. What needles are you using and how are they set? You may need to screw the needles in a couple of turns to get a richer bottom end.
 
They are 34's with 0-2 XL needles. A needle adjustment is the next step for sure, but I'm not sure if I have to lean them out or richen them up, my butt dyno isn't as astute as some.
 
If you have to keep the throttle cracked you are likely too lean on your low end settings.
 
Interested to see where you go with these. I really like Lectrons, but never tried using them on a 4 stroke. Been a while since I used them - still have some around here somewhere - do they still offer the clear fuel bowls? I always liked to see the fuel level directly even though it mostly isn't needed.
 
Sav0r said:
If you have to keep the throttle cracked you are likely too lean on your low end settings.

Agree. Try one turn at a time and see what happens and if it gets worse, try one turn at a time in the opposite direction.
 
At least the needles are 'fat' enough that making new ones is easy (although I haven't made any for a long time)
You may need multiple transition tapers to get close on part throttle cruise
 
crazypj said:
.... part throttle cruise

Please explain this "part throttle cruise" phenomenon. Carbs are basically digital devices On or off - or in this case open or closed. Ahh. I see. You mean when going around a long sweeper where WOT is too much..

All joking aside, part throttle is likely to be clean enough but may require a few different needles to get there.
 
It's why Lectrons are so much 'fun' on the street, you ain't flat out everywhere all the time (no matter what 'we' tell people ;) )
 
Back
Top Bottom