TZR250 3MA
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Have made a new setup to investigate the Speed limiter, instead off all loose components I combined them all together to give a better overall view.

You See the:

-TPS sensor
-RPM (display)
-Airjets 1 and 2
-Speed limiter
-Ypvs motor

The New setup in action.

The location of the Speed limiter is mounted at the side of the Speedo meter.
Where a metal tap goes through the optics when it hits 180kmh
Or when bike is standing still, metal tap is between optics to. (same signal is given)

It can be removed easy as its bolted on place with two small bolds

Her you have a close up off the Speed limiter circuit board:


-OUT(B) - If not connected it is making a 10V signal connected it gives a 5V signal
-GND     - Mass
-OUT(A) - signal (3V and 5V)
-IGN      - 12V

Connection on the IC:

-Pin 33 is the speed limiter circuit receiving two signals (3V or 5V)

Small description how it is working:

When the bike is kicked in to live, the metal tap is between the optics. (bike standing still) This gives a 5V signal to pin33 on the IC. (from the 3MA CDI)
This signal is the Sign for the IC to use a different ypvs curve, with allows the bike to just hit the 180kmh (Stop the power off the engine revving past the 10.500rpm)

When the metal tap is not between the optics, The IC receives a 2,88V signal on pin33.
This combined signal is the sign for the IC to use the correct ypvs curve

When the Speed limiter is not connected, the IC holds the 5V on pin33 giving the sign to the IC that it should use the ratted curve (safety curve)
When the Blue/green wire is disconnected, the signal on pin33 is 5V, the IC to use the ratted ignition curve.

The 3MA1 ignition is self supporting. (does not need a battery)
Even When there's no battery at all, and the charging spools are removed (complete Charging system removed), The bike can run.
But the IC holds the 5V on pin33 the IC uses the safety curve.

From what I can measure The two aftermarket speed limiter's (M-max and posh-firm) only giving the signal (metal tap not between optics) to the IC on the 3MA CDI

This is the same signal coming from the speed limiter circuit board when its connected outside the speedometer.

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