Very cheap handheld digital tachometer - any good?

[MapisM]

I am considering the purchase of one of these tools.
Did anyone try (or heard about) that, or any other similar bit of kit?
Considering the price, I'm not too scared by the idea that it could die upon the third usage - if not the first...
But buying a POS is something that annoys me regardless of its price, hence this thread!

 

[Kawasaki]

Worth a shout at that kinda dosh
What do you want one for Mapis?

 

[simonfraser]

just bought one of those, used it twice so far.
does what it says on the can.

 

[Gumpy]

Had one for years, used it couple of times for setting tick-over revs and recalibrating the tacho on the boat. Works well does what I need

 

[MapisM]

What do you want one for Mapis?

Just a crosscheck with analogue instruments, whose accuracy leaves something to be desired.
I'm not concerned about the last 10rpm of course, but I'd like to sync the engines exactly at my usual cruising speed (using the digital thing), and then check what I read on the dashboard gauges, for future reference.

Happy to stand corrected if I'm missing something!

 

[Elessar]

I am considering the purchase of one of these tools.
Did anyone try (or heard about) that, or any other similar bit of kit?
Considering the price, I'm not too scared by the idea that it could die upon the third usage - if not the first...
But buying a POS is something that annoys me regardless of its price, hence this thread!

Wanted one for a while to calibrate my analogue tachos. Just ordered - thanks for the link and will let you know.

 

[Kawasaki]

Just a crosscheck with analogue instruments, whose accuracy leaves something to be desired.
I'm not concerned about the last 10rpm of course, but I'd like to sync the engines exactly at my usual cruising speed (using the digital thing), and then check what I read on the dashboard gauges, for future reference.

Happy to stand corrected if I'm missing something!

Ahh, I see
Sounds good to me
Order one then
Try it
If it’s carp let us know
Save us lot bothering
:encouragement:

 

[Bouba]

I am considering the purchase of one of these tools.
Did anyone try (or heard about) that, or any other similar bit of kit?
Considering the price, I'm not too scared by the idea that it could die upon the third usage - if not the first...
But buying a POS is something that annoys me regardless of its price, hence this thread!

How do you use it? Put the reflective strip on the crankshaft pulley?

 

[MapisM]

Precisely.
Nothing that I invented, btw: any half decent mechanic has something like that in his toolbox (together with an IR-gun for temperatures, which I already have).
I learned from some of these folks that they don't trust the onboard instrumentation even with electronic engines, though the differences (if any) are much smaller than with analogue gauges, obviously.
Otoh, for using it just in a few odd occasions, I would never fork out 500 Eur or so for a Fluke 931, which afaik is the reference tool in this field.
But at 10 quid or so, there's no need for sophisticated man math...!

Anyway, since I'm far from being in any hurry, I'll wait to hear from Elessar his impressions - thanks in advance for that!
What Loddon reported is already reassuring, anyhow.

 

[5teve]

I have one for the reasons above. Looks the same but sourced from an electronics shop here. Works with reflective strips on the crank. Accuracy seemed good, but it was a bit fussy about alignment with the strip. Highlighted the port rev counter being out by 400rpm at 2200... Purposely done I think to mask a knackered turbo... (Found before checking rpm) I was trying to source the issue of the sticks being way out of line at cruise....

Steve

 

[BruceK]

I bought this one 3 years ago. It's been faultless and accurate
https://www.amazon.co.uk/Demino-GM8...rds=digital+tach&qid=1560982075&s=diy&sr=1-41

 

[rosssavage]

Good cheap Chinese bit of kit. Had one for a few years now, works every time.

My port flybridge tacho over reads by 100rpm - guessed by throttle stagger, proved by this.

 

[Assassin]

Not that good overall but for its intended use it is well up to the job, and at that money you can't go wrong.

You can get the strip in rolls and cut some off to a desired length.

 

[BartW]

P,
I've one onboard, (slightly different model)
you can borrow it, (I hope I have reflective strips left)
it is perfect to calibrate your analog gauges.

 

[MapisM]

Excellent B, thanks in advance.
No worries for the reflective strips, I still have them on both engines since the seatrial upon purchase! :encouragement: