I have an 87 200x which runs fine but I have to ask? Where does the ignition trigger from? It has to go to the cam gear doesn't it? There are no connections to the head for a trigger. If it is crank triggered, how the heck does that work? I'm guessing it is a gear in the crankcase?

Rex

 

Hey Rex.

You are right about the crank trigger [pulse coil] being down in the bottom end rather than the topend like the older 200X models.

There are multiple magnets along the outside rim of the flywheel that works just like the old cam rotor with one magnet on the older engines did. There is only one trigger [pulser coil] and it is mounted in a stationary position on the inside of the left crankcase cover.

There are no differences in these systems pertaining to how they perform regarding electricity. The reason that a crank triggered ignition is prefered though is because it removes rotational inertia from the drive train.

Resistance on the crankshaft is better than on the camshaft...and that is why nearly all engines now use this type of system.

 

I understand that crank triggering is more precise, no chain slack, etc., but how does the ignition "know" which rotation the cam is on?

 

I think you are somehow relating ignition triggering with the turning of the camshaft based off the camchain.
There is no relation between the two.

The camshaft, ofcourse is connected to the crankshaft by the timing chain,...so there is no reason that the position of the camshaft should ever play a part in the ignition firing unless the timing chain is extremley worn and stretched.

 

But it is a 4-stroke, so how does the ignition know whether the piston/valves are in the exhaust/intake or in the compression phase?

 

it fires twice and one is just wasted.

 

Ok....I see where you are going with this now. Sorry I misunderstood you earlier.

The CDI box is what controls spark to the ignition coil

The CDI box knows when to do this based on the pulses from the pulser coil in the bottom end.

It doesn't work any differently than it did with the older 200X engines.
You just have a different "point of signal" [crank vs. cam] for the pulser coil.

That is the simplest and easiest way that I know of explaining it here.

There is no room for error with this setup and is why mechanically operated points systems are no longer used today.....not to mention having to clean and sometimes replace worn points every 20 hours of use....LOL