How To: Use a Small Engine Tachometer & Set Engine Speed | Reviewing the Cheapest One On Amazon

In this video we take a look at how to use a small engine tachometer, adjust our engine speed for maximum RPMs, and see if the cheapest one off of Amazon is any good.
Link to the tach I'm using: www.amazon.com/gp/product/B07...
We are using my re-powered Ariens Compact 22 snow blower as an example to make sure we are running within the original engine's specifications.
How do you know if you need to check and adjust your engine speed?
-When you're doing a small engine swap and need to match the performance of the outgoing motor.
-When you are dealing with generators, you want to make sure your RPMs are in-line with the manufacturer's specifications. (RPMs have a direct relation with a generator's output voltage. Make sure you're not frying anything you plug in.)
-When your machine doesn't seem to be performing as well as it should. Your RPMs may have dipped below spec, and a quick adjustment can fix that.

[@johncollins8304]

I just saw this on some website (something 'wizz') but couldn't see comments so searched Ytube. Thanks for this. I've stayed away from anything with wires and/or that spoke of hour - counter but you've just taught me this type should do what I want -' just to test speed occasionally on different engines. I have a branch shredder with Honda GC 135 that just stalls when I push a correct diameter branch in. My Briggs vibrating doodad shows only 1900 rpm! It needs to be 3600 so I need to check the reading and figure out how to increase the speed (I don't think it's as simple as yours). •Steve 's Small Engine suggests to bend the lower tab on the governor that has the little spring attached. But for now I'll buy one of these things when I've checked out the reviews. THANK YOU!

[@stephenschrader6087]

I've used five of these cheap amazon or ebay tachs and they all tested accurate against Faria Beede tachs. 3-4 loops tightly wrapped with zip tie works well.

[@CookedAnimalEater]

Oh...now you're an expert with the 7th loop.

[@totallyfrozen]

Lucky! Yours came with instructions.

[@nowayjose20]

Need to bring it up to operating temperature first before setting the set screw.

[@CuriousKL]

A heads up. The lock nut that holds the throttle lever can loosen because of vibration. Tighten that lock nut just a bit and apply some light lubricant. Don't use WD40. Then make your speed adjustment.

[@baldeagle242]

Thanks for sharing this. I bought one of these some time ago and never could get it to read correctly. I'll have to get it out again and play around with it.

[@bl9531]

Same here, the readings were ridiculous… was finally forced to go by ear …. Which is very annoying… but better than following the recommendations of a false reading from a tachometer

[@ramazandoganer7468]

very usefull video

[@jdprice3043]

THANK YOU

[@craigjoseph9374]

Thanks!!!

[@biggusbestus551]

Guess the Honda 216 engine is not typical they call for 3,100 rpm no load rpm ... thanks for the video I have one on order.

[@mrbrown6421]

DIAGNOSTIC PRO TIP: Wrap 5 turns around a round metal bar 1/4" diameter, 1 inch long. Wrap that with duct tape to keep wire on the bar, and not unwinding like the Graz attempt. Zip tie it to a spark plug wire and start your engine. When done adjusting engine RPM, cut zip ties and move to the other cylinder, if necessary. You have just created an inductive bar. It steals the pulse from the plug wire, and applies it to your metal bar, where the device accurately detects and registers it. I cannot tell you the device is accurate, but you just removed a lot of the variables. -- The Great Nicolas Tesla revealed these secrets 100 years ago. -- North Central Florida -- 9.10.2023

[@wryanddry2266]

5:01 Secure the wire using a clove hitch on each end. Also maybe a couple dabs of hot glue.

[@OomptzMusic]

Cool 👍

[@mosesheho5884]

Nice

[@LogiForce86]

Tip, buy a small batter clamp and solder the wire to the clamp. That way you can easily attach and remove the tacho on any engine.

[@PaulHenreid]

The Operating Instructions for this self powered digital tachometer state: "4 stroke installation, wrap pickup wire around head of coil. 2 stroke installation, wrap pickup wire around spark plug lead."

[@louvega8414]

Good vid, thanks Graz. I have a DR650 motorcycle which has no tacho and runs a carb, which needs adjustment according to conditions. I was looking for some way to meet and check the idle RPM. Any reason you can see why this would not work on the bike? It's a single cylinder engine with two spark plugs.

[@GrazGarage]

Hmm that’s a a good question… For a single cylinder w/ 2 plugs, the tach is just going to think it is a 2 cylinder engine. (Since you are just wrapping the tach around one plug wire and it fires every-other power stroke) You would probably just need to set it at 1P2R (below). By default, this model comes set for single cylinder engines. From the manual, to switch the firing pattern: 1) Hold “S” until “1P1R” starts flashing. (1P1R is for single cylinder, “1 Spark for 1 Revolution”) 2) Then click on “S” to cycle through the different settings. 3) For a 2 cylinder engine you’ll want to see “1P2R”. (1 fire per 2 revolutions) 4) Let your desired setting flash for 10 seconds and it will set your firing pattern. Hopefully that helps! (And if all else fails, you should be able to return it pretty easily if the seller on Amazon allows it)

[@louvega8414]

@@GrazGarage Ahh, glad I asked. Thanks again!

[@mickgatz214]

Very informative video! you gotta be careful when winding the wire. Too many, and you'll get a 'false' higher RPM Too few, and you'll get a 'false' lower RPM (there's a bit of a trick to tweak them apparently) I've basically got the same tach that I bought about 5 year ago. It has a replaceable battery (CR2450). However, I just found it in my box of junk and decided to hook it up. Not sure if the hours will be erased once the battery is depleted. I expect it so for a cheap unit. :) Fingers X'd Cheers! Mick

[@georgeiceman867]

So how many turns i need to wrap it for best accuracy ? Thank you.

[@RS-ge4dz]

@@georgeiceman867 5 like the directions say

[@Slippindisc]

@@RS-ge4dzmine didn’t come with any directions lol I almost threw away the wire

[@mrbrown6421]

THAT is incorrect. The wrap count does not matter. Wrap the entire wire into a bundle, and hold it NEXT to the spark plug wire. Then do the 5 wrap count. Same number.

[@Thomas-nz4uh]

I purchased one of these for my Husqvarna 128 LD weedeater. The manual says the idle rpm's are between 2800-3200, so I have the rpm's set to 3,000, but the max speed should be set to 11,000 rpm's. My question is, how would I get this techometer to show 11,000 rpm's?

[@stclairstclair]

I think I'm going to verify this unit with a handheld tach-meter, I'm a retired mechanic and I want to see if I can successfully wind my sensor wire near the coil under the engine cover, I just built a sweet vintage style go kart.

[@_JamesBrown]

You running chainsaw motors?

[@thegunnut221]

You wrapped the wire around the double insulated part of the spark plug lead. Inaccurate reading if wired like this.

[@kevinspahr6632]

Can the wire be permanently wrapped around the spark plug wire and mounted and used as a tachometer for my motorcycle?

[@GrazGarage]

Hmm, I don’t see why not… The refresh rate won’t be as fast as an actual OEM tach, so I’d be cautious.

[@rohan8611]

What should be the setting for 4 stroke 1 cylinder engine?

[@GrazGarage]

For a single cylinder it should be 1P1R.

[@stanleykeith6969]

I just ordered one of these and I was wondering if you can cut some of that extra wire off. I'm glad its on a snow blower. I also have an Ariens 24". Please let me know about the Extra wire. Thanks for sharing.

[@GrazGarage]

You should be alright to cut the excess wire off. I am not mounting mine to one specific motor, so that’s why I’m leaving the excess on. Just leave yourself enough wire to do the few wraps around the coil to get a clear signal, and you should be ok to cut the extra off for tidiness.

[@hphillips7425]

I am on the fence getting one of these.

[@jamie66233]

They're very affordable! 18.99 on Amazon with 18 different carb tuning screwdrivers!

[@cc123456789]

On the tachometer what did you set it up as 4p1r?

[@justgjt]

It shoud be set as 2R1P for a 4 stroke engine

[@fckjb284]

I haven't found an Amazon one yet that's accurate!😖

[@jbigg43971]

I have the same tach with no manual. Don't you have to set it for a single cylinder engine? number of fires per rotation? thanks

[@GrazGarage]

By default, this model comes set for single cylinder engines. From the manual, to switch the firing pattern: 1) Hold “S” until “1P1R” starts flashing. (1P1R is for single cylinder, “1 Spark for 1 Revolution”) 2) Then click on “S” to cycle through the different settings. 3) For a 2 cylinder engine you’ll want to see “1P2R”. (1 fire per 2 revolutions) 4) Let your desired setting flash for 10 seconds and it will set your firing pattern. Hope this helps!

[@myparadiseonbantayanisland9030]

3600 rpm is usually the redline for single cylinder lawnmower type engines.

[@goranpavlovic9051]

Brush cutters go over 11.000 rpms

[@myparadiseonbantayanisland9030]

@@goranpavlovic9051 those are 2 stroke engines. I'm trying to find out what the real redline is for 4 stroke single cylinder engines like the honda gx390 copies from china, 420 cc 15hp engines.

[@goranpavlovic9051]

​@@myparadiseonbantayanisland9030ahh, gotcha

[@goranpavlovic9051]

Why rpms not steady? They going up and down

[@KAONANAONA]

Trust the equipment to give you the correct rpm reading. It will be much more accurate than by ear! It's impossible to guess an accurate rpm. I don't think anyone can count to 3600 in a minute.

[@socalRooster]

What’s the point of having a tachometer on a small engine you’re not racing it

[@rp6879]

It is a big deal by not putting a sign on it. You blew the motor up and had to replace it. Now it's not working like you want it to with a new Harbor Freight engine. Moral to the story. First check for engine oil!😂🙈😎

[@jimdillon938]

Read a lot of reviews and watch many videos on these tachs and most people don't like them. They are not accurate and you end up guessing on your settings.

[@GrazGarage]

For the price, and my use of getting the RPMs in a general ballpark on unknown engines, it’s worked just fine. If you needed a more accurate or permanently-mounted solution, I’m sure there are more expensive or even OEM tachs for whatever application you need them for.

[@jimdillon938]

Maybe you could do another more in depth video of other tachs and compare pros and cons and their accuracy and price ranges then give your recommendations.

[@markrusk2870]

Incorrect way to wrap, too many loops and not tight. Not accurate the way you installed.

[@brianbradburn]

These things are not accurate.

[@kembalimerindu4448]

Wastentimee,,speak many long