Laser tach?

[rusty ol ranger]

Will these work to check crank rpm to set/check idle speed?

https://www.amazon.com/Handheld-Digital-Tachometer-Non-Contact-Measuring/dp/B0828K3W9H/?tag=959media-20

 

[Curious Hound]

You should be able to measure crank speed with it. But you can not set timing because it doesn't have a trigger signal to synchronize with spark.

 

[rusty ol ranger]

You should be able to measure crank speed with it. But you can not set timing because it doesn't have a trigger signal to synchronize with spark.

No i got a good timing light. Just wanna use it to check/adjust idle rpm on various things

 

[pjtoledo]

should work if you can get reflective tape to stick on an oily pulley/shaft.

 

[Curious Hound]

should work if you can get reflective tape to stick on an oily pulley/shaft.

Could clean the pulley before applying the tape. Just a thought. I know it's radical. But...

 

[bilbo]

We use strobes at work for checking RPM of machinery. They work great as long as the RPM is very stable. I tried to use it at home on a lawn mower engine but it didn't work real well. The RPM moves around a little bit and I couldn't get a great read on it, but it got me close enough for a lawn mower. I'm not sure how precise you'd like to be, and I'm not sure if the laser one would suffer similar issues. I bought an automotive digital multimeter off ebay a while back that also does RPM using a signal from the coil. It was not very expensive, and may work better than the laser one.

 

[Dirt Squirt]

As a small engine specialist for the last 45 years, I would highly recommend Briggs and Stratton #19200 tach. It is called a sirometer, and measures harmonics of any rotating shaft (even electric motors), with a fine wire that you move in and out by turning the dial and vibrates in a circular pattern on the end loop when you hit RPMs as read in the window of the devise. Just place it on top of the motor on any hard mounted component (not plastic shrouds). Takes a while to develop a feel for its function, but is cheap at $24, requires no batteries. You would be surprised how accurate it is compared to a digital tach that costs 4 times the price, usually within 10 rpm or so.

 

[rusty ol ranger]

We use strobes at work for checking RPM of machinery. They work great as long as the RPM is very stable. I tried to use it at home on a lawn mower engine but it didn't work real well. The RPM moves around a little bit and I couldn't get a great read on it, but it got me close enough for a lawn mower. I'm not sure how precise you'd like to be, and I'm not sure if the laser one would suffer similar issues. I bought an automotive digital multimeter off ebay a while back that also does RPM using a signal from the coil. It was not very expensive, and may work better than the laser one.

Thats mostly what i want it for. My ear for idle speed isnt as good as it used to be. As long as it gets me close im happy.

As a small engine specialist for the last 45 years, I would highly recommend Briggs and Stratton #19200 tach. It is called a sirometer, and measures harmonics of any rotating shaft (even electric motors), with a fine wire that you move in and out by turning the dial and vibrates in a circular pattern on the end loop when you hit RPMs as read in the window of the devise. Just place it on top of the motor on any hard mounted component (not plastic shrouds). Takes a while to develop a feel for its function, but is cheap at $24, requires no batteries. You would be surprised how accurate it is compared to a digital tach that costs 4 times the price, usually within 10 rpm or so.

I thought about that but i would also like to use it on vehicles with a carb

 

[Dirt Squirt]

Works on any engine or motor with a rotating shaft.