how many missing teeth?

[mill383]

Just wondering if I should do 1 or 2 missing teeth? Engine is a single cylinder 4-stroke. It is a kickstart machine. 320 cc. Was planning on a crank triggered 30-1. Was going to set it up as a 2-stroke, so I don't need a cam trigger. Wasted spark is ok. Am using LS2 coil.

Dave

[grippo]

I would use 30-1. There is nothing to gain from a larger tooth gap, the ECU has no problem recognizing 60-1 tooth wheels. In fact a larger gap can make detecting the gap more prone to seeing a false tooth in the gap. Plus the timing across the gap will always be a shade less accurate since you are predicting over a longer time interval.

[mill383]

Thanks Al. That's what I'll do.

If anyone's looking for ideas for a speed sensor, I'll be using an ABS sensor from a failed front bearing assembly, 2000 Silverado C1500 Chevy truck. Nice and small, and works well (at least during my bench test).

Dave