My s1r9a9m9 replication!

[Shanti]

When I look at your schema you're currently using, something does light up to me.

After the bridge the DC will be a 100Hz only pos-side sine-signal. So if the firing rate gets higher than this frequency, you will have e severe problem, for the loading voltage of the cap will change with the current sine voltage, so you will have a very uneven firing, with some firings at very low cap voltage (could be even near zero!).

So my suggestion would be to use either a much higher freq AC-signal. Or to us some big cap-battery after the bridge to have there a stabilized 320VDC, and to charge the firing cap with the help of a FET from this DC level. And the FET should obviously be in 0ff condition when you want to fire. Otherwise qour whole cap battery gets discharged in the spark...
A simpler solution would be to insert a resistor between the cap and the cap-battery to restrict the amps flowing from the battery, when the arc has established. At the same time, this also restricts the loading current for the cap. Which ist good, for the cap. But the loading time should certainly remain smaller than the firing rate...

Just again some thoughts by myself...In case anyone is interested...

But as I calculated, usually the firing rate of a ICE is not very high, so it most probabely can work directly with only a bridge rectified 50Hz AC, but it would surely then have some 100Hz Power differences overlayed...

[capacitor70]

Today I have taken trials with my 125CC 4 Stroke bike. Its not starting at all with water, not much bulb glow (may be plasma is not generating properly), not a single fire is observed. Spark plug gives good plasma checked before putting it into bike.
Then I given gasoline to start it normal, but it is not starting on gasoline also.
I have not checked spark plug after trials, Then I started plasma, still it is not running not a single fire, but suddenly it given a very very huge blast, sound came from silencer.... Blast sound is very very loud my neighbour come to my home to see that blast...I am scared to start it again....

[Unicron]

Probably residu off gas in exhaust that exploded maybe an Afterfire/back-fire

can it be you have a leaking valve? or maybe the spark is also sparking somewhere it should not?

http://en.wikipedia.org/wiki/Back-fire

[Kineticon]

Did your bike work well before starting these tests? If so, then you need to make the same adjustment of the carburetor as said earlier: put bigger fuel jets.
Also check the needle valve in the float chamber.
Could it be a timing problem? Check the proper tuning of this system.
Use another sparkplug outside the engine conected with wires and check the presence of the spark/plasma, trying to start the bike normally.
Try to clean/dry the carburetor after you use water. If water remains in it, the gasoline will pass very difficult to the engine, sometimes beeng blocked.
Could you make a clear photo of the sparkplug electrodes? One that had been used in that bike before testing with water.
The backfire occurs in the manifold. There is another type of problem, that makes big explosion-like sound in the exhaust pipe/muffler. Its cause may be the wrong timing, weak spark or carburetor running rich.
It seems that changing the fuel type recquires a lot of tuning...
Good luck!

[capacitor70]

Working hard to get it run..... Plasma system is on the bike, tomorrow I will take more trials.
as I told earlier water shorts spark plug, spark plug must get wet but not shorted with water on its tip. this create problem.

Probably residue off gas in exhaust that exploded maybe an Afterfire/back-fire

same thing is in my mind.