ESE's works engine tuner

[wobbly]

"I'm not keeping up, they were running leaner by exhaust reading to run richer in the blast pot?"

NO - when globs of fuel do not vaporise, they pass thru the engine unburned and this gives rich readings on both egt and Lambda.
If this situation is " fixed " by the tuner jetting down, we then get a chemically lean condition in the combustion space but this then reads as "normal " for
best power at say 13:1.
This is what happens to the KZ2 engines that regularly deto the piston and head to death,when crap fuel is being used with what the driver thinks are safe jets.
In the quoted article, they kept the bad fuel under control by not going leaner than 12:1,this saved the engine, but made alot less power.

[wobbly]

Fuel vaporisation is very good with a carb such as the Lectron, and for years it has been seen that these carbs are way less sensitive to A/F ratio than your average VM round slide Mikuni for example.
If you read the marketing blurb by SmartCarbs, they are telling us that the fine mist from that carb is way better than that we get from what we would regard as normal injection.
But running super high pressures and or air over fuel as we see in Etec etc may ameliorate this , dunno.

[WilDun]

Fuel vaporisation is very good with a carb such as the Lectron, and for years it has been seen that these carbs are way less sensitive to A/F ratio than your average VM round slide Mikuni for example.
If you read the marketing blurb by SmartCarbs, they are telling us that the fine mist from that carb is way better than that we get from what we would regard as normal injection.

Not really up with the play here, but will ask a question anyway, so here goes! - will that "fine mist" remain a fine mist when it passes through the curves of the transfer passages? - is it possible that it could be "centrifuged" into droplets again before it reaches the cylinder?

[F5 Dave]

I typed this before but lost it. I've been following the SC progress on the GasGas forum. They've had manufacturing issues & delays on the cast versions. Some have had luck, but others not so much fun. & much adoo with one-type-fits-all needles needing tiny iterations to get them in ballpark - seemingly with people in Auss having different fuel & thus different requirements.

Makes me wonder how they will last long term with tiny amounts of wear, will they be like early Dynojet kits which ripped out.

Hope they do sort it, it does promise so much. Ironically the renewed talk has other bolting up Lectrons & getting good results.

[wobbly]

To answer the two questions, yes fuel mist will drop out of suspension and become raw fuel sitting on the walls of the ducts.
Conventional wisdom tells us that in a 4T this can be minimised by making the inlet port walls surface finish equivalent to 180 grit wet and dry.
Now this is interesting as in most cast 2T transfer ducts end up being around this number - and so called " beautifully " cast ones and those polished up by
expert tuners end up way smoother - loosing power in the process.

The other question around the SmartCarb fuel needle issues.
I told them right at the beginning that the only way to enable fine tuning of the carbs - especially when on a twin Banshee for example, was to run a powerjet with very small jet increments as Lectron
did with great success very early on.
But they are /were so enamoured with their own cleverness re the insensitivity of the carb thus not needing to be fine tuned, I was ignored.
The possibility was / is there to finely emulsify the powerjet fuel using the so called AdjustaJet principal of having a variable air bleed into the powerjet suction circuit but sadly
some horses dont even like water.
Those carbs do work supremely well, but seems for now the only way to get fine tuning is to be fucking about sanding the needle tips with a digital micrometer in the other hand.

[Frits Overmars]

...when globs of fuel do not vaporise, they pass thru the engine unburned and this gives rich readings on both egt and Lambda.

I don't get this, Wob. When fuel passes through the engine unburned, the oxygen in the A/F-mixture will pass through the engine unused.
That should give high (= lean) Lambda readings, shouldn't it?

[fixer]

The ESE boys might have only half a clue, but it's a good half. And they have a functioning dyno now. With the addition of a small aluminium plate to raise the barrel, a small mod to the exhaust manifold and a little fiddling with the ignition timing, my Aprilia RS50 with it's Conti pipe and Doppler top end has gone from 10hp to 13.6hp. Woo hoo! Evidence below:

[wobbly]

Sorry Frits I gave the wrong impression with that statement, but as per the article I quoted above ( from Dynotech Magazine a superb mine of info on 2T testing )
"unvapourised fuel only displaces O2 in the combustion space " so we do have excess fuel dropping the egt and if the engine is then leaned down
it will deto due to the actual lean condition in the chamber.
But if using Lambda we cannot run fuel that has low amounts of light front ends at the "normal " best power ratio of 13:1 as the unburned droplets contribute nothing to the combustion process.
So the actual " burning " A/F ratio in the chamber is in effect lean.
As in the Dynotech example they gave they had to run under 12:1 or the engine would have been destroyed by deto in an instant, when running the new fuel with zero RVP.

[wobbly]

And as for the 1/2 clue guys I have obviously offended at ESE ( not my intention at all ) I strongly disagree with the idea of taking a 2T cylinder
with very average timing figures, trying a bunch of pipes " just to see what happens " then jack the cylinder up and retry the pipes.
As I did say, lifting the cylinder MAY give an improved result, and who knows what pipe would then work with that combination.
But the bottom line still remains for me is that IF the cylinder had been measured, the result put into a CAD program and the timings/STA numbers matched correctly
you would then KNOW what the result " should " be with a specific pipe - and be able to move forward knowing its for sure not the ports causing big holes or power loss.
The end result you have now is for sure better than what you had, but if it was done " properly " I also know for sure way more power is still on the table.
Look at how much power is able to be extracted from that Athena 50 cylinder with matched STA numbers - if I then stuck some random pipe onto that setup
and it made 7 Hp less at the crank ( ie about what yours is doing now ) I would be looking seriously at the pipe , as I know the porting is correct.
Surely that approach is a better way of getting a really good result - maybe I am wrong again?

[TZ350]

And as for the 1/2 clue guys I have obviously offended at ESE ( not my intention at all )

No .. not offended but of course you can expect a ribbing for being so blunt......

The end result you have now is for sure better than what you had, but if it was done " properly " I also know for sure way more power is still on the table.

We are absolutely sure your right and this makes Fixer and his bike a great test subject to demonstrate that, as he is a very good rider with a bike he is developing in progressive steps.

Its great that Fixer is posting all the details of his work complete with dyno graphs of his progress and its all happening quite quickly (in Bucket terms).

He is currently running second in F5 and has a realistic shot at first so we know he will ride the wheels of the thing on the track, and so along with the development progress we will get real on track racing performance feedback too.

Currently with cut and try and a few good guesses its at 13.5 rear wheel hp and a 3.5k rpm spread of power, hopefully Fixer will keep working on it and we will get to see how it all unfolds and where Fixer gets to with this tuning project of the after market 50cc road bike 2T cylinder as it progresses from the usual starting place of cut and try to doing it "properly" by bringing ever more science to the party.

Wob, we value your input, maybe this is the year we see NZ's first documented 18rwhp F5 2T.

[wobbly]

I was dreaming late last night ( about 2Ts - what else ) and thought thru the statement that Frits was questioning ( a complement to a very skilled bullshit detector that man I must say ).
Maybe the logic of " unvapourised fuel only displaces O2 in the combustion process " leads to the Ex gas then also being low in O2 so the Lambda reads rich ?
I dont know to what extent ie what % of O2 can be displaced by fuel that is never burnt, and if that level is then sufficient to affect the Lambda reading.
That then leads me to the question - wouldn't a continuously misfiring engine read rich on the Lambda, and isnt that then the same end result as unburnt fuel droplets passing thru an engine?
This is too early in the morning for this - I need strong coffee.

[Grumph]

If oxygen makes up 20% of the atmosphere then in theory, 20% of the volume of unburned fuel equals the amount of oxygen displaced...

But you'd expect a lower proportion of oxy in the end gases anyway - so maybe the effect is bigger than at first appears.

maybe i need something stronger too.....

[wax]

Wobbly are you saying you think the lectron is the better carb size for size ??

[wobbly]

I have done the tests on a Superflow and the so called HV Lectrons will outflow a size for size Mikuni or Kehin easily , and ,as say a 38mm HV has a 34mm venturi
behind the slide it acts like a much smaller carb at 1/2 throttle.
In Europe I know they are using 30mm Lectrons on 50cc race engines with great success.
The SmartCarb does not have a venturi, but has an egg shaped bore at the slide that probably does the same thing.
They also have an aux venturi above the top of the entry trumpet, that is connected to the bowl air space - and it is this that gives the carb its auto adaption to air density,be it weather or altitude.
This for sure works a treat, with no jetting change when climbing Pikes Peak - but at the moment they do seem to be having endless trouble getting the things into the ball park at sea level.
At this stage Lectron do have a huge range of incremental needles to suit any application and also have a powerjet with very fine flow sizing that makes fine tuning a twin super easy.
I have just got a 30mm SmartCarb here for a Giggle project , so if someone with 1/2 a clue wants to do some testing im sure we could arrange something.

[wax]

I have done the tests on a Superflow and the so called HV Lectrons will outflow a size for size Mikuni or Kehin easily , and ,as say a 38mm HV has a 34mm venturi
behind the slide it acts like a much smaller carb at 1/2 throttle.
In Europe I know they are using 30mm Lectrons on 50cc race engines with great success.
The SmartCarb does not have a venturi, but has an egg shaped bore at the slide that probably does the same thing.
They also have an aux venturi above the top of the entry trumpet, that is connected to the bowl air space - and it is this that gives the carb its auto adaption to air density,be it weather or altitude.
This for sure works a treat, with no jetting change when climbing Pikes Peak - but at the moment they do seem to be having endless trouble getting the things into the ball park at sea level.
At this stage Lectron do have a huge range of incremental needles to suit any application and also have a powerjet with very fine flow sizing that makes fine tuning a twin super easy.
I have just got a 30mm SmartCarb here for a Giggle project , so if someone with 1/2 a clue wants to do some testing im sure we could arrange something.

I would love to take you up on that I have an 86cc ported scooter engine i have just finished building. Its a shame I am in australia, some say i have not even 1/2 a clue so best i sit this one out lol
Thanks for the information I am deciding if to try a lectron or to stick with my 28mm pwk on my new 86cc engine