sirometer for propping?

[surlyjoe]

has anyone ever used one of these vibration tachs to prop with? they say they are accurate within 1-2%.

 

[steelespike]

Re: sirometer for propping?

I think I would check it first through the rpm range of your motor before messing with a prop.<br />Then if you are sure where you are at give it a try,keeping in mind it could be 100 rpm over or under what it says.If you think about that it might be as much as 200 rpm off if you figure a high or low error.Another thought will it register the vibrations of a 2 stroke the same as a 4 stroke?And of course there is the number of cylinders to consider.<br /> To be even more long winded if your motor is running at a designed max of 5,000 but tach indicates 4,800 and you change props to an indicated 5,000 you would be running 200 rpm over your max.You'll never know where your at.

 

[surlyjoe]

Re: sirometer for propping?

well, I have an old big twin, I dont think I can over rev it, as the cutout kicks in before then, but I see what your saying. I think its supposed to pick up the ascillation of the crankshaft rotation, so the number of cyliders/strokes shoudldn't matter.<br /><br />if only I had something with a tach to test it on...lol

 

[Solittle]

Re: sirometer for propping?

What is a sirometer & how does it work?

 

[surlyjoe]

Re: sirometer for propping?

http://www.treysit.com/TREYSIT_Presserei_Schwalmstadt/Sirometer/sirometer.html

 

[roscoe]

Re: sirometer for propping?

Get yourself a tinytach.com and have a real tach, they have one for your motor.

 

[surlyjoe]

Re: sirometer for propping?

ya, I have four or 5 e-bay tachs on my bench. still haven't found the right one. I really dont want the digi style, and the extra wire in the motor well is a drag, as I keep the motor inside, so no more 1 plug removal. I was thinking about mounting one under the cowel you could see with the door flopped down, but I would still have to order it with a custom lead and make some kind bracket for it. it would be a lot less ghetto to just get an old one too mount in the dash like its suppposed to be. but in the mean time, I'd liek to get the prop right, plus I need a new hand tach for general use, I was thinking laser, but this looked real interesting. Just wondering if anyone has ever used one?

 

[roscoe]

Re: sirometer for propping?

Interesting, yes.<br />Still not quite sure how it works, website is "foreign", .<br /><br />Do you have to order it from Germany, or have you found a US retailer?