is it possible to damage a JB performance vr board with rpm?

[Blue 12]

im fighting 1 gremlin after another. after having issues with synch loss at 11500 rpm with just about every type of resistor combo (in line and parallel). i decided to cut half of the teeth from my 24-1 wheel thus creating a 12-1. i removed all resistors and it revved clean to a nice 12500 pull and then a 12800 pull. now it will barely read cranking rpm. i get a little blip on the screen now and then during cranking but nothing solid like before. it started a couple times, but died soon after. is it possible that i hurt the board with higher rpm?

[racingmini_mtl]

The higher the RPM, the higher the voltage generated by the sensor. So in theory, you could hurt the board. But it should be able to handle a lot (over 100V) before that becomes an issue. But that also depends on whether the board is located in a place that allows it to cool if those high voltage conditions last for a while.

What would be affected are the big resistors on the board. What you could do is to measure their resistance (with the sensor not connected) and see if you get about 10k.

Jean

[billr]

Check the resistors, but it is probably time to go back to your "wheel" thread. The 24 teeth was never your root problem. Many of us run higher tachin frequencies with 60-tooth wheels on automotive engines. The tooth shape has to be well-matched to the sensor, and I have found that filled teeth work better than missing teeth with VR. Was that wheel originally a "missing-tooth" type, or did you grind a tooth off to create it?

[Blue 12]

the 24-1 was an oem wheel, not modified. that is until i turned it into a 12-1 wheel yesterday

[Blue 12]

The higher the RPM, the higher the voltage generated by the sensor. So in theory, you could hurt the board. But it should be able to handle a lot (over 100V) before that becomes an issue. But that also depends on whether the board is located in a place that allows it to cool if those high voltage conditions last for a while.

What would be affected are the big resistors on the board. What you could do is to measure their resistance (with the sensor not connected) and see if you get about 10k.

Jean

my board is mounted in a way that only 1 side is accessible, can i test it from the "bottom"

this is an old pic, yes all the wires are on now, i dont have a current pic

[racingmini_mtl]

The resistors are surface mount components so you only have access to them on the other side.

Jean

[Blue 12]

thank you
i think my bike just hates vr sensors. i connected some zx10r wheel speed sensors a couple weeks ago to an external jb board and couldnt get anything from them either. i decided to get that working after the bike was tuned, but now its not looking good for making the july race with anything megasquirt related.