Classic 35

Michael72

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Just finish a revamp on a classic project...whats the RPM on these? no joy online can get close enough by ear but she has mileage and would like to keep it right. thanks

9D902 2006B3 0210285
 

Michael72

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Just finish a revamp on a classic project...whats the RPM on these? no joy online can get close enough by ear but she has mileage and would like to keep it right. thanks

9D902 2006B3 0210285


:anyone:
 

bertsmobile1

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All vertical shaft engine spin around 3000 rpm.
If it is on an 18" mower 3400 is max speed as it gives a blade speed of around 20,000 ft / min which is the old max allowable blade tip speed.
The 4 strokes generally spin a bit slower 2800 to 3200, blue smokes 3,000 to 3,600.

So if you rreally want an exact speed, work out the blade tip circumference in feet, divide 20,000 by it and that is the rpm if the blades are bolted diectly to the crankshaft.
 

Michael72

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All vertical shaft engine spin around 3000 rpm.
If it is on an 18" mower 3400 is max speed as it gives a blade speed of around 20,000 ft / min which is the old max allowable blade tip speed.
The 4 strokes generally spin a bit slower 2800 to 3200, blue smokes 3,000 to 3,600.

So if you rreally want an exact speed, work out the blade tip circumference in feet, divide 20,000 by it and that is the rpm if the blades are bolted diectly to the crankshaft.


Excellent stuff thank you.....:thumbsup: got one of those cheap tach's the other day....does the job but you need to add a small strip of reflective tape to the object you want to check (failed to mention that in product description) ... pain in the ***
 

bertsmobile1

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If you are going to play with small engines have a good think about one of those combined tacho timing lamps.
I have a couple and some times my friends who borrow then actually give them back so I can use one,:smiley_aafz:
While the strobe is not much use as small engines have fixed timing the tacho function is excellent as it counts sparks.
Mine are designed for motorcycles so will do RPM's for 1,2,3,4,6 & 8 cylinder engines.:cloud9:
 

Michael72

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I had a decent one but took a bad fall... this one is not worth a curse....:rolleyes:
 

bertsmobile1

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Apparently there are a few apps for the BatPhone uses that make them into a 1/2 decient tacho might be worth a look if you have one of those phones that do every thing except make phone calls.
 

Michael72

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Apparently there are a few apps for the BatPhone uses that make them into a 1/2 decient tacho might be worth a look if you have one of those phones that do every thing except make phone calls.

Thanks for info!.....I just download tach onto android phone....someone posted a vid on you tube showing his phone matching the rpm counter on his car.... too late to fire up a mower here but will test bright n early :smile: link to vid https://play.google.com/store/apps/details?id=com.javiery.rpmgauge&hl=en
 

Michael72

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....might as well be pointing a slice of bread at the mower!..... another usless app on the phone! :laughing:
 
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