Suzuki 2 Strokes

So I am having a devil of a time getting my bike started. I have checked and double checked everything that I can think of including making sure there IS spark. I have set the timing to both the 28mm and 32mm marks that the Powerdynamo suggests. I have cleaned out the carbs making sure that the jets are clear. But still, the only thing I can get out the of the bike, is a popping with starting fluid. I have brand new pistons in it, and the compression is about 110 PSI. I cannot figure out where the problem lies. I currently don't have pipes on it as I am waiting on getting some expansion chambers welded up. I am regretting changing so many variables at one time, but it really needed an overhaul. Now I just need a place to start from for tuning, but that is really hard when it won't even fire.

Any suggestions I am open to, and will try to run down.

I know basic 2 stroke theory requires back pressure from the pipes to run well, but it should at least fire, shouldn't it?

Also, anyone have an idea of how to test/adjust timing on a powerdynamo unit that isn't running a battery?

Thanks for anything.

Swap the plug leads side to side. Sounds daft but...........
Then if that fails, it might be an idea to make sure that the plug sparks when it's supposed to and the timing mark actually lines up when it should. Timing disc on the crankshaft and a dial gauge to find tdc required for that. I take it that the spark is big fat and healthy? Never worked on a power dynamo system, prefer points and a battery, but the idea should be similar.

There's no back pressure really, it's a resonant pulse, and the thing needs to fire to make one. That's really how an expansion chamber works really - a bit more complicated than that, but that's what holds the charge in where it's needed, rather than letting it all out of the exhaust port.

Hello Sharky,

What model PD do you have? It sounds a bit like you have the timing somewhat out. My Race PD has a duel output coil so it does not matter which lead goes to which plug but yours may be different, try swapping the plug leads. Timing can be adjusted by moving the stator within the elongated slots or moving the rotor on the taper.

Cheers Geoff

Sorry about the late post, been busy couple weeks. I have the non-race lights set up. I have tried reversing the leads, but then I figured they were 180 deg out from one another. I plan on testing the carb curcuits again, but I will also try to test light the spark, and try to make sure that I am where i need to be when the spark hits, but have to find a way to send voltage to the light. Just again at a loss as to where to start, but will take your suggestions. Thanks all.

So just to make sure, the resonance chamber shouldn't stop it from ticking over entirely? I would figure that.

You do have the pistons round the right way? And the slides in the right carbs?

The Carb slides, yes. The engine pistons, not so sure anymore. They were the wessen (i think) pistons and came with no markings, and not a lot of information on ring fitment or which side was exhaust/inlet.

Please tell me they can go either way. Otherwise, inform me a way to check orientation and give me a couple weekends to tear everything apart again, haha.

Also, seemed to catch a pop a little better as I screwed the air screw in on the 30 pilot jet, so I upsized to the next highest I had on hand, 35s. Nothing. Ordered 32.5 just to see what happens. Just to be honest there were some buggered head bolt holes that need helicoiled, so I am not opposed to pulling the engine again, if anyone has an idea how to check the orientation on the pistons.

With the pistons at the bottom of the stroke, use a small mirror in the exhaust port to see the “R”, “L” & arrow markings on the top of the pistons.
Also could use a digital inspection camera in the exhaust port or spark plug hole.

Check, and both have an engraved II with an arrow pointing toward the exhaust port. Both are pointing directly out the angle of the port, so I assume they are right. Any thoughts?

Also, remembered they were Wosser, not Wessen.

That sounds right