RPM activated switch to save motor from nitrous blow up

[crutschow]

The max speed governor on my car's engine works only when I am passing a slower vehicle on a 2-lane road and a big truck is coming towards me.
They say it is for tire safety. Maybe I should slow down.

There should really be an automatic short emergency delay on the governor (say 30 seconds) that would allow for just such a situation. Certainly the tires wouldn't overheat in that short a period, if that's the real concern.

 

[audioguru]

A timer would be dangerous.
I think the speed governor should have an over-ride push-button.

 

[Roff]

How long does it take to get from 14000 to 14500 RPM in first gear on this bike, especially if you hit an oil slick and lose traction, or miss a shift? Not very long, I'll bet. The LM2907 (or any similar frequency to voltage converter) has some time lag, which could be disastrous. I would consider doing a digital period measurement on the tach output, which is instantaneous. The noise immunity is worse, but you could do some digital filtering or a sanity check (comparing with previous results) to improve it, if necessary. These also have lag, but it could be less than the F-V method.