The Lectron - Review (vs SmartCarb)

[singletracker]

That's interesting. I don't have the issue with the hanging idle, and mine has good throttle response at low RPM's as well. I did have a bit of a lull in power when I was running it richer, but I wouldn't call it a bog.

92 octane, Motul 800, 48:1, RB head mod with stock compression.

 

[Jakobi]

My idle screw is definitely not wound up too high. I'm well aware that it can cause hanging idle issues. I physically and visually set the slide height to only be a few mm open and the bike sits at a very low tickover and will generally stall after about 30 seconds. Same same as I always had the PWK setup and the way I'm happy.

Interesting info above. I found a quarter turn richer settled the hanging idle issues instantly, however it still feels a touch lean in the lower rpm. It reminds me of the Suzuki needles, where its silky smooth delivery, but just doesn't quite have what I'm looking for. I've got no doubt that I can get this carb to fuel well and Daves supplying a richer needle to play with which I personally think will be a leap in the right direction. The top end is very very nice. You can never have too much!

 

[swazi_matt]

from what you have shown so far it goes on what Corey has said previously that the lectron is more of a drag racing carb working awsome at full power, but not as well in between.

But I don't want to lead your thoughts on this and am eagerly awaiting the APT report

 

[Jakobi]

from what you have shown so far it goes on what Corey has said previously that the lectron is more of a drag racing carb working awsome at full power, but not as well in between.

But I don't want to lead your thoughts on this and am eagerly awaiting the APT report

I disagree completely.. From the moment it was installed it has been right in the ball park. I have made 3 adjustments to the rod, which totals a change in needle length equivalent to 0.5mm. Think about the distance between a clip position with a Keihin. It would have to be at least 2mm between adjustments. You also have to consider I was previously running what I would consider to be a pretty angry/aggressive needle taper profile so what I may be feeling as a lack of snap/punch could be the result of things being smoothed out.

Ask Corey if they offer different metering rods for different carbs/engine configurations and I think you'll find they do. The APT carb has the added bonus that the dial adjuster for the needle height is external to the carb which allows instant adjustment where the Lectron needs the slide removed first. I'm not sure if its method of picking up fuel is the same or not, but I'm looking forward to receiving mine I've been a bit skeptical as to how well it will work from the start. The old saying if it sounds too good to be true it probably is. After trying the lectron I am confident it will be really good. Just not sure if it will be great! Either way, big props to both manufacturers.

You also have to configure that I am obsessively complusive when it comes to tuning this so while I harp on about how I think I could get it better here or there, it will honestly probably be the best jetting a lot of people have ever experienced even if running slightly off perfect. Worth the coins? Yep! A single carb and a single needle has equalled the state of tune I had spent endless hours changing brass to achieve as well as the coin spent buying needles and jets.

 

[singletracker]

I would like to add a little to what Jakobi explained.

I like the smooth Suzuki needle in the PWK even though it doesn't have the punch of the N3 needles that Jakobi likes. Because of that I figured if anyone wouldn't like the tunability of the Lectron/SC it would be Jakobi because he likes the aggressive needles. I'm glad to read that isn't the case. With the Lectron I feel like I have the smoothness that I like and I gained back nearly all of the punch that the N3 needles offer. Very smooth, strong power, and very easy to tune compared to the PWK. Drag race carb? I don't think so.

 

[dmcca]

Jake start the 3-2 needle at the same length you are currently on with the existing 3-1 needle... 50.50mm unless you've changed it since... Then go from there. That should mean the mid range jetting will be similar to before and the bottom end richer... In theory.

 

[GMP]

Jake,

The key difference between the Lectron and APT is the APT is compensated by float bowl pressure working with signal at the nozzle. In addition to atm pressure and air density, this pressure will change with velocity in the air bell, as thats where the pressurization port is. I don't know what you know about control systems but think of it as open loop vs. closed loop. I get it, not all the detailed math but I understand the theory. I think that if it was easier to get where they wanted to be they would have done so. Smarter guys than you and I figured this one out.

 

[Jakobi]

Very true Glenn

I can see how this could give the SC the edge, particularly at auto compensating at changing altitudes and temperatures. Would it adjust for engine loads too? Even then the metering rod and its profile still has to be matched correctly, or else it will just be correcting for a setup thats not quite right.

 

[GMP]

The point is the closed loop nature of the system will compensate for changes around the same metering rod. So yes engine load, size, etc. to a limit. Thats why it works on everything from a 125 Husky to a 300 GG with the same rod. This is like a very simple, mechanical alternative to closed loop EFI. You have to think about it differently. This buy is nothing, these guys are after the big nut, OEM contracts. You won't get there with a non-compensated system in 2013 and beyond.


Sent from my iPad using Tapatalk HD

 

[AZRickD]

The compensated circuits are a dandy concept *if* the new check valves keep the carb and motor from flooding during a tip-over (as advertised).

 

[singletracker]

Time will tell, but it is probable. I can tell a difference in how my bike runs when going from the upper 30's to the mid 50's with the Lectron, but not enough that I feel like I have to make an adjustment. If it's running crisp in the mid 50's it feels a little lean in the upper 30's.

 

[singletracker]

Only after making an adjustment to the metering rod.

 

[Jakobi]

Makes sense to me Glenn, particularly if thinking of the metering rod more like fuel injector. A certain sized injector can supply fuel over a certain range of conditions. I guess you are trying to say that the pickup on the SmartCarb works in a similar way in conjunction with the metering rod.

Tuxedo. Lifting the slide or lowering it introduces more or less air so will have an effect on the idle and off idle response too. A sign of being too rich on the metering rod (as described by Lectron) is that you will have the slide raised quite high using the idle screw. I also noticed while playing that by lifting the idle up a bit more I could introduce some minor hesitating off idle. I have noticed this on both the carbs though. The PWK and the AS2.

I have also noticed that the Lectron definitely doesn't pick up fuel based on engine load. You still get into the situation where you either jet to pull strongest in higher gears and higher loads and deal with some richness in the single track, or jet clean down low and lack torque in the higher gears. It still requires you to compromise a bit, and again its probably much more noticable being in a 250 than a 300.

 

[swazi_matt]

ok i stand corrected

 

[Jakobi]

Only half corrected though Matt. It still sounds like the SC may offer even more of a benefit again, albeit at an increased price point. Considering the coin some people drop on bling/exhaust systems, I can see both products giving exceptional bang for the buck. Couple that together with ease of use and its smiles all round.

I look forward to receiving the SmartCarb and comparing my thoughts and findings. After testing the lectron I'm definitely looking forward to it more than I was a few months back.

Dave, would you be interested in testing the SmartCarb in your bike and/or on the Dyno once it arrives too? I realise you're a Lectron dealer now, but I also know you don't bs and want to be able to honestly communicate both pro's and con's to your customers, tailoring to their needs.

 

[GMP]

You have to look at APTs mission, its not just about replacing PWKs on racing two strokes. Its about an EFI alternative at a much lower price point that will allow emmisions compliance previously not possible. And yes, time will tell if the carbs live up to there expectation. Only a large population on various machines will provide an accurate picture.

I'm sure the Lecton is close, especially when dialed in for a certain machine ridden is relatively consistant conditions. A PWK is primative in comparison to either. You jet for hit or snap at a certain RPM and TP by creating a "hole" in the power before that range. You don't give extra, you take away and then give back. If fuel was always optimized, you would feel only the efffects or the PV opening curve, ignition map, and general tune of the engine like pipe and porting. Ten years ago I had a Cannondale 440 that I did a lot of EFI mapping development on. I had the enduro version, it was very smooth and did not feel fast, although it was. The MX and SM versions felt faster. The difference in the mapping was an intentional flat spot or "hole" in the fuel matrix and timing before advance continued, giving the impression of a hit in power. An N3xx needle does exactly the same thing.

 

[dmcca]

You have to look at APTs mission, its not just about replacing PWKs on racing two strokes. Its about an EFI alternative at a much lower price point that will allow emmisions compliance previously not possible. And yes, time will tell if the carbs live up to there expectation. Only a large population on various machines will provide an accurate picture.

I'm sure the Lecton is close, especially when dialed in for a certain machine ridden is relatively consistant conditions. A PWK is primative in comparison to either. You jet for hit or snap at a certain RPM and TP by creating a "hole" in the power before that range. You don't give extra, you take away and then give back. If fuel was always optimized, you would feel only the efffects or the PV opening curve, ignition map, and general tune of the engine like pipe and porting. Ten years ago I had a Cannondale 440 that I did a lot of EFI mapping development on. I had the enduro version, it was very smooth and did not feel fast, although it was. The MX and SM versions felt faster. The difference in the mapping was an intentional flat spot or "hole" in the fuel matrix and timing before advance continued, giving the impression of a hit in power. An N3xx needle does exactly the same thing.

Interesting.

Jake do you think theres any chance the flat or constant feeling of the lectron from idle to 3/4 may actually be giving extra power in an area where the keihin had a dip or trough before coming on hard, therefore giving the impression of more power from the keihin? As GMP explained above.

If only you weren't a few thousand Kms away cause itd be great to get it on the Dyno and do a back to back comparison... See if the lectron smoothness is hiding more or less power.

By the way I'd definitely love to test the SC... As you already know I want to get to the bottom of how each one differs in real world testing.

 

[Jakobi]

Interesting.

Jake do you think theres any chance the flat or constant feeling of the lectron from idle to 3/4 may actually be giving extra power in an area where the keihin had a dip or trough before coming on hard, therefore giving the impression of more power from the keihin? As GMP explained above.

If only you weren't a few thousand Kms away cause itd be great to get it on the Dyno and do a back to back comparison... See if the lectron smoothness is hiding more or less power.

By the way I'd definitely love to test the SC... As you already know I want to get to the bottom of how each one differs in real world testing.

I had considered that Dave, but not so. The area of the lectron that I'm not 100% happy with is only around 1/8 - 1/4 throttle. Its like if you try to take off in 2nd gear it just wants some more fuel in this range. Everywhere above is fantastic, and the bike still has some snap and punch in the midrange. It has definitely filled in the void that Glenn referred to with the N3xx. I know exactly where that is as I was always dealing with the transition and usually clutching to modulate the hit and bring the bike onto song the way I wanted. Thats smack bang in the mid range. The N3CW starts rich and then leans off. The void is right where the second taper changes from lean to rich.

With the lectron, if you were relating to a PWK setup is the same as the needle diameter and pilot. I'm hoping the other needle you have sent will be just what I'm after. Its also very possible that I could also just richen the current rod another half a turn and find improvements across the rev range. More testing needed.

 

[dmcca]

I just tried another 38 lectron on my bike... Its a CR250 not a gasser but this is a Lectron thread so its still relevant... Started with the 3-1 needle at 50.25mm length... Felt great, insane midrange, good bottom end but idle felt just a touch rich... Only evident by the fact it would load up a little if it idled for more than 30sec of so. Changed the needle to 50.50mm length, same as what you've been testing, and instantly it felt too lean from idle to 1/4 and a bit down on power compared to the previous setting. Went back to 50.25mm and that instantly felt better... Rode with it like that for a few hours and it was very very nice. Starts easily, idles well and pulls like a freight train. Still feels a touch rich at idle but only noticeable if you've been stationary for a while... and I'm being very picky about it really.

Have you tried the 50.25mm needle length yet? It was a noticeable difference on my bike and may fix your lean idle.

 

[Jakobi]

Yep Dave. Basically you sent it up at 50.50mm. I installed it and rode it. Liked it but thought it could be crisper in places. I went to 50.75mm and it hung idle immediately. Went back to 50.50mm and rode it and it was good. Went out on a real ride and loaded it up with some real terrain. Thats when I experienced a hanging idle only after riding hard. I then went to 50.25mm and it ran well. I agree with you. A little more burbly off idle than it was, but then cleaned up quick. Felt a bit flat just off idle, and then a super strong mid and top. I'm running the power jet an extra 1/8th of a turn out from where you had it and the top end is awesome. I'm trying to upload a video at the moment.

Basically, in terms of normal PWK actions, I'd be looking at going a step richer on the needle diameter, and dropping the pilot one size.