ESE's works engine tuner

[Grumph]

[QUOTE=TZ350;
Two advantages I can think off straight away.

1) Width of the power spread, if a normal crank has a power spread of 4K then a 2:1 crank would be 8K. An 8K wide power spread from a 2T would be handy.

2) The magic exhaust port duration of 192 for reinforced superimposition of the wave action in the chamber would be easier to achieve with the lower blowdown STA required for a motor doing only half the rpm it was before.[/QUOTE]

The apparent gain in power spread was one of the selling points of Ricky Main's Geneva wheel motor/con trick....IMO the same applies here, not true.
You've still got a piston reciprocating at a finite - and as wob has pointed out, pretty limited velocity. So this crank setup simply means half as many revs at the output shaft for the usual piston speed.

[TZ350]

if a normal crank has a power spread of 4K then a 2:1 crank would be 8K. An 8K wide power spread from a 2T would be handy.

An 8K wide power spread is meaningless. Any difference between the maximum and minimum rpm values of a power band is meaningless.

It is the ratio between those maximum and minimum rpm values that counts: http://www.kiwibiker.co.nz/forums/sh...post1130525788

I prefer to work not with a powerband but with a power range, which I define as the highest rpm of a power curve, divided by its lowest rpm.

http://www.kiwibiker.co.nz/forums/sh...post1130525788 It is all double Dutch to me at the moment, I don't have the slightest clue about what the post is trying to tell us, its a real head scratcher for me. So I will need to make a study of your concept of "power range" and get my head around it because it looks good, thanks for the heads up.

[karter444]

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[husaberg]

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Thanks for the imput we will all mull it over and consider that thoroughly, Frits are you able to comment on that with out breaching the non disclosure order?

[Yow Ling]

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Great post ! keep them coming

[karter444]

Hi I have been reading all the info on this forum with interest for a few months now it really helps amateur engine and pipe builders like myself . I have an engine problem that I need help with , we race 3 kx 250 engines in the nz superkart series and for the past 6 months or so have been trying to diagnos an engine electrical miss at about 7000 rpm plus under acceleration . we did everything electrical you can think of and did most things more than once, finally not thinking that this would fix the problem we swapped the flywheel from another engine and the miss was gone . so then obviously needed another flywheel , ordered one on e-bay fitted to the engine that was now missing a flywheel [ie different engine from the one that had the original miss ] engine miss returns . flywheel has same partnumber , same dimensions and looks perfectly fine . ignition is ignitec , trigger coil and ignition coil wiring has all been separated . Can anyone offer an explaination I don't want to keep buying flywheels until I get one that works
cheers Richard

[Yow Ling]

Hi I have been reading all the info on this forum with interest for a few months now it really helps amateur engine and pipe builders like myself . I have an engine problem that I need help with , we race 3 kx 250 engines in the nz superkart series and for the past 6 months or so have been trying to diagnos an engine electrical miss at about 7000 rpm plus under acceleration . we did everything electrical you can think of and did most things more than once, finally not thinking that this would fix the problem we swapped the flywheel from another engine and the miss was gone . so then obviously needed another flywheel , ordered one on e-bay fitted to the engine that was now missing a flywheel [ie different engine from the one that had the original miss ] engine miss returns . flywheel has same partnumber , same dimensions and looks perfectly fine . ignition is ignitec , trigger coil and ignition coil wiring has all been separated . Can anyone offer an explaination I don't want to keep buying flywheels until I get one that works
cheers Richard

is that all you changed? nothing else, carb?

[karter444]

no changed nothing else 100% sure its flywheel or flywheel related , read somewhere on this forum a post from wobbly about the length of the trigger coil striker plate causing an ignition misfire so he may be able to offer an explanation
should have mentioned that the miss with the flywheel off e-bay wasn't nearly as bad as the original misss and disappeared when the good flywheel was put back on

[husaberg]

no changed nothing else 100% sure its flywheel or flywheel related , read somewhere on this forum a post from wobbly about the length of the trigger coil striker plate causing an ignition misfire so he may be able to offer an explanation
should have mentioned that the miss with the flywheel off e-bay wasn't nearly as bad as the original misss and disappeared when the good flywheel was put back on

Only thing that comes to mind is the air gap on the pulser and loss of magnetism on the flywheel.
Any damage evident from main bearing failure on the inside of the flywheel (ie smearing) or on the pulser protrusion. Is the insides still round?

[speedpro]

The triggering bumps are easy to compare so I expect you have done so. What may be a little less obvious is if you are using the rotor to generate power for the Ignitech and the magnets are "off". If it's rotor related and the triggering is the same I would be looking very carefully at the generated supply current. Not just the DC level but also any AC and if possible look for noise on the supply side. I wonder if the generator magnets are displaced in relation to the triggers if that would have any effect, perhaps one rotor is busy generating electricity exactly when the Ignitech needs it.

[karter444]

we are not using the charging system to charge the battery that runs the ignitec and as I understand it the magnets wont have any effect on the ignition system as they are only there to work in conjunction with the charge coils to charge the battery and supply voltage to the original ignition system . the charge coils have been removed .so now the fjywheel is only there to switch the trigger coil on and off , my feeling is that its not a physical problem as such more of an electrical interference problem .

[seattle smitty]

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One of the best posts I've seen; exactly expresses my own bafflement over all these Ryger leaks and hints. Bravo, karter444!! I wish I were as articulate.

[senso]

Can you mount the trigger closer to the fly-wheel?
Use a feeler gauge and gap it around 0.5 or 0.7mm.

Consider using a trigger/pick-up from a foul-stroke, from an R6, they are small compact and made to spend their lifes submerged in hot oil, they are a bit more rugged than almost all the 2 stroke ones that operate in "free" air.

[Grumph]

Can you mount the trigger closer to the fly-wheel?
Use a feeler gauge and gap it around 0.5 or 0.7mm.

Consider using a trigger/pick-up from a foul-stroke, from an R6, they are small compact and made to spend their lifes submerged in hot oil, they are a bit more rugged than almost all the 2 stroke ones that operate in "free" air.

I'd go closer again. I've gone as tight as .3mm. If the pickup is mounted in the cover, measuring can be difficult - plasticine is usually the easiest way to get an accurate figure. The suggestion to use a more rugged pickup is very good.

[wobbly]

What is the diameter of the rotor and what is the trigger lobe length.
In reality the lobe length only needs to be as wide as the magnetic trigger pole.
If the lobe is too long the rising voltage waveform from the upward bump can decay to zero and give a false trigger signal
before the actual dropping edge has left the poles magnetic field.
Re electrical interference, of course you have resistor spark plugs and a resistor cap ( measure both to ensure the resistor element isnt fried ).
And the other trick is to tightly wind the two wires together from the trigger up to the ECU, by holding the ends in a battery drill and slowly winding it over.
This gives good common mode rejection of spurious noise.