Briggs Vibra Tach

[wagonwheeler]

My dealer recommended a Briggs Vibra Tach (PN 19200) as a very inexpensive but accurate tach for the occasional user. He couldn't remember their limit and has ordered one in. When it comes in we'll check it against thier shop tach just to see - I'll let yall know.

Anyone here used one? I've read elswhere about how they are 'surprisingly' accurate, but no info on how high they can measure.

MSRP is $18 from briggs. Works on any engine (even electric) and you can just about set it anywhere on an piece of equipment to check the rpm. Sounds worth $18 for the novelty even if it won't handle high revs.

Chaser

 

[Fish]

It works well, but a little more difficult to use than the high tech models.
Most of the members here would have a problem with the "wiggle" factor,
as they have deep psychotic issues involving their childhood.

I must admit here, that I was abused as a teenager, but it was all self
inflicted..........................

 

[Chris J.]

Vibra Tach. That sounds so naughty my wife would probably let me buy one .

 

[Simonizer]

My dealer recommended a Briggs Vibra Tach (PN 19200) as a very inexpensive but accurate tach for the occasional user. He couldn't remember their limit and has ordered one in. When it comes in we'll check it against thier shop tach just to see - I'll let yall know.

Anyone here used one? I've read elswhere about how they are 'surprisingly' accurate, but no info on how high they can measure.

MSRP is $18 from briggs. Works on any engine (even electric) and you can just about set it anywhere on an piece of equipment to check the rpm. Sounds worth $18 for the novelty even if it won't handle high revs.

Chaser

I used one for a few years in the late 80's. They work on resonant frequency. I would estimate their accuracy to be +/- 5% or so. This is going back awhile but I seem to remember their range being from 700-20000 rpm. The accuracy would not be constant across this frequency spectrum but at worst would be accurate to within 8-10%. Be careful with getting false readings from harmonics. Any first-order harmonic will give significant deflection with this tool. The key to using it accurately is knowing the approximate frequency (RPM) you are trying to measure and "dialing it in". Cheers.

 

[JeffHK454]

Simon put it very well .... just one small bit of info , the high limit on the one I have (Briggs) is 50,000 RPM.

I don't own anything that will use up a 20K limit , so whats the diff!


Jeff

 

[wagonwheeler]

Thanks for the info.

I plan to have the dealer check it against thier tach so that I can see for myself the relative error and how to read the wobble per that error. I'll have em run it on a saw and a mower so that I can take note of the readings at 3600 rpm and 13k range. I figure it'll keep me out of trouble anyway.

Chaser

 

[wagonwheeler]

Vibra Tach arrived today. The shop had already played with it some and we ran it a little more when i got there. Measures to 25k but the graduations get much tighter on the high end and so accuracy diminishes.

Ran it on an Exmark mower w/ Kohler 23. Read 3450 and thier wireless digital tach also averaged 3450.

Ran it on a MS390 and they both averaged a hair over 14k at WOT and 10k at fast idle.

Certainly worth the $18.15 MSRP. Definitely not as convienent or precise as an inductive. Well, precision above 10k anyway.

Simonizer was right on about knowing the approx RPM and dialing it in. Wouldn't want to hold WOT and monkey too long w/ it. I suppose holding the saw in a vise by it's bar and strapping the tach to it would leave one hand free to throttle and one to adjust.

BTW, it's German made in case anyone was curious.

Chaser

 

[Fish]

Of course Simon was right, he is an engineer, and uses words like harmonic.

 

[JohnL]

Harmonics... multiple frequencies at which the wiggle exists, but less wiggle than the fundamental, hopefully.

 

[Blowdown1]

yeah, well I bet Simon is playing much harmonica with his shoulder messed up.