Many have seen this monster thread and various user reviews of the APT carb. http://www.cafehusky.com/threads/apt-smartcarb.28324/ My personal testing showed the APT to be no joke and an amazing carb. Now the Lecton is in my hands thanks to Vinduro for letting me check it out while he is laid up. I'll take some pix ASAP but this is a cool looking unit. Clear see through float bowl, Same looking flat metering rod, "Power jet" top end adjustment (screw adjustment). I just pulled it out of the box and took a peep, will get more info tonight but here is the measurements for those concerned about fit. Reed block side - 1.678" / 42.65mm Air box bell - 2.377" / 60.39mm Total length - 3.812" / 96.84mm will post the stock TMX carb dims this afternoon. Looks promising. Kelly
Snapped some pix Fuel inlet, Idle (big brass), clear bowl. Line from bottom of bowl goes to the the top of the carb and that spring right where the "T" is in Lectron is for the top end adjustment. It draws fuel from the bowl to add to what the Metering rod does. Intake side. Metering rod seen here at the bottom of the slide (like a needle on a standard slide) Note Choke is on the wrong side for my application but it big and should still be pretty EZ to get to. Here you can clearly see the pickup tube for the top end nozzle.
Is it going on your WB165? Stupid question, lol. Hopefully it will stack up well against the SmartCarb well.
So here is my take after investigating two of these metering rod carbs. These "metering rods" are basically taking the needle to the next level to cover all ranges. This in theory makes some sense as it does not change circuits and thus no crossover or some circuits not working well with others. The key seems to be that the metering rod needs to be behind the slide for draw and velocity I am guessing. The slides in the APT and Lectron are quite different. The APT is much thicker and has like two guillotines. The APT metering rod seemed larger (guess) and had a different looking nozzle. The APT does not have the high speed main jet adjustment the Lectron has (although it id not seem to need it either) So they both basically use a needle to cover everything from pilot to main on a standard carb. That said I would think the metering rod, slide, carb shape, etc would be very important. Also It seems like this design would need to be very load / draw dependent (like all vacuum fed carbs are) so that a wide range of needs are addressed. It all makes perfect sense to me and APT seemed to get it right. Oh, it seems this system wound me more water tolerant as it can draw it through instead of getting caught in a pilot or main. This to me is another semi large advantage as many times I have had to limp through or fix water in the carb issues. We will see if this earlier version of the idea already was there of the APT has some forward progress on this tech. Oh, unfortunately all i will be able to do is put the carb on and blip the throttle as my shock is out for a rebuild. Will get rirst ride Friday if all goes well.
What size of carb, 36mm ?. and thanks so much for keeping us updated on your testing, Very Valuable information . . I trust your views so I will be sitting on the fence until the verdict out.
Mikuni TMX dimensions http://www.carbparts.com/mikuni/tmx_dimensions.htm Keihin PWK dimensions http://www.carbparts.com/keihin/pwk_jetting_and_dimensions.htm
Great info so far and will decide on either the lectron or the smart carb after reading some reviews. Thanks Kelly!.
Still looking for a dyno comparison between the Mikuni TMXX with Suzuki jet needle and RB divider plate mods (like mine) vs APt vs Lectron. Sorry, I'm an engineer, I need facts, not opinions before I spend a grand.
Interesting and informative post. I remember reading some of that over there. My first thoughts on the matter is the keyhole design and altitude compensation (none vented pressure changing bowl) are the main differences. Sounds like the Letron is an older generation roundbore and meter rod design and needs to be adjusted more. As for the keyhole shape the engineer in me thinks you could compensate for that with the meter rod cutout to correlate with the air volume regardless of shape. The APT might be smoother because the shape makes it ramp up quicker but you would think you could still design the rod to be right. Again I could be talking straight out my ass. Just tossing crap out there. I just installed it and fired it up...
Funny. I am also into high fi stereo (well kinda) and there is always the guys that have to measure sound and flat and those that buy because is sounds good to them. I'm a sound good, could care less how it measures. For me the carb is the same. I put it on and went wow, that works well. Took it off and went, man I wish that APT was back on there. I miss it. All I need to know. I ride for fun not numbers he he he I would not drop a grand on it. The stock carbs work great. The APT, to ME works better. How much that is worth to you is a personal decision. I have no horse in this race, someone else bought the carb and I knew nothing about it. I was an innocent bystander :>) I will never sell APT carbs, they don't even have a dealer program. I like the APT, it works. Completely unbiased opinion. Your mileage my vary.
