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4stroke cdi on 2 stroke

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I got a vortex on the other bike it quite rips but it rips also the wallet quite a bit.

Procom runs around 130 US vs Vortex close to 600. Any other CDI producing developer around for a YZ250 2007?

In regards to destroy the engine it should fire the spark still every stroke wouldn't it?

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Yes it would. The biggest problem which I can foresee is that four strokes need more advance as revolutions rise, two storkes need less. IIRC typical two stroke has zero advance at high load high rpm. Any advance would kill it immediately. But the trigger is probably off anyway on the flywheel so no one knows where it will actually spark.

But wiring a 4 stroke FI bike ecu onto a two stoke might need a bit of improvisation.

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Sure I agree, the flywheel is easy to manipulate, but some boxes come reprogrammable so there I basically could convert the 4 stroke CDI into a 2 smoke cdi :smashpc:

I found this article > here

Edited by arnego2

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Most 4S run off a battery (12 volts DC), most 2S run a straight off the CDI (70+ volts AC).

If you do get a CDI that can run off your stator, there is a lot of work to get the ignition timing right. Not all crank positin sensors are in the same position in relation to actual max retarded ignition. Your article appears written for bikes from the 70's

Buy a unit designed for your bike.

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Not many sensors on the pre injection bikes so far I'm aware. That I have to improvise is also clear but will the connection fit, meaning are the plug ins of the 4 stroke cdi identical to the 2 stroke? The maps can be changed, you get a cd with it.

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None of the modern MX 4-strokes run off a battery.
I swear I am Drain Bamaged somethimes. Thanks for catching the mistake.
Not many sensors on the pre injection bikes so far I'm aware. That I have to improvise is also clear but will the connection fit, meaning are the plug ins of the 4 stroke cdi identical to the 2 stroke? The maps can be changed, you get a cd with it.
What you need to do is compare relative crank position sensors (meaning when the sensor signal fires off in relation to the piston position). Most CDI's that are programmable only have so many degrees you can play with.

Chances are you'd be ok assuming the resistance of the sensor is within limits, the stator output and so on. It would be a shame to try to save money only to discover the CDI you bought falls out of range for the bike you are trying to put it on or even worse, burns it out.

I doubt the plugs will interchange. You may have to remove the pins from your old CDI and graft them on to the new one as well as swap shells of course. Highly doubtful too, color codes will match up so some very careful sleuthing will be needed to get that right too.

A fair amount of experimentation and risk to save a few bucks IMHO.

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