Optimate test – cranking & alternator, TS-121, 12V tester for battery state of charge, cranking performance and vehicle charging system

Bought this to keep in my bike’s toolkit. A day or two after it arrived, my car wouldn’t start. Was able to correctly diagnose that the battery needed to be replaced. It had enough voltage at rest, but dropped too low during cranking.

Straightforward product, does its job well. One small issue is the cable is not very long. So, for my trunk mounted battery, I cant bring the meter all the way to the dash to see it. I set it on the trunklid and was able to view it in the rear view mirror, reversed, but still understandable. It takes the guesswork out of diagnosing the charging system and battery state.

Hardly any vehicles these days come with voltmeters that continuously read the battery voltage. Digital voltage readouts are available as aftermarket items and are not difficult to install. But, even if you have an aftermarket digital voltmeter they only hold their readouts for the display update time which is only a fraction of a second. Because the lowest cranking voltage occurs very quickly a digital voltage display won't reliably detect the lowest voltage and hold it the way the Optimate does. THIS IS THE BEST INEXPENSIVE TOOL TO SHOW THE CRANKING VOLTAGE. A thousand-dollar digital storage oscilloscope would be better... but you can't throw one of those into a motorcycle hard case for portable use. Use this tool to check the resting, cranking, and charging voltages occasionally, jot them down in a logbook, and this ONE TOOL will give you an indication of the health of your motorcycle battery, alternator, and starter. If it shows that everything is ok it will provide peace of mind. If it shows your battery, alternator, and starter are dead or dying, it will pay for itself by telling you where to troubleshoot. This tool is recommended by Tracy Martin in his book on Motorcycle Electrical Systems.BTW, I have a 5-year-old Shorai lithium battery in my bike, and this works perfectly with it. My resting volts are in the green (around 13.4 volts) (lithiums are higher than lead-acids), my alternator output voltage is in the green (14.1 volts), and my starting voltage is 8 volts... in the yellow. But everything else is ok and the bike starts just fine, so I'm not worried.

Not as accurate as I would have wished for, when tested up against a higher quality commercial grade multi tester the crank voltage was off by 2 volts and the charging system test off by .7 volts. It is probably a good tool if you don't have a higher end multi tester.

Readings are very fast.

Worked as it should and was able to see if my batteries were too low or charged perfect. Also indicates on the back how healthy your battery is.

Great tool that has worked well for testing motorcycle batteries and charging systems. My only complaint is the material used for the housing. It feels pretty cheap and I am concerned that it will break in use.

This unit is small in size feels plasticky but solid as it needs be. Worked right out of the box1 once connected shows the status of the battery2 then it shows how good is the battery in terms of cracking power (how good the battery in giving you power trying to start the vehicle) its simply how long you can keep hearing that sound when you push start or turn your key to ignite the engine3 then it shows how good is your alternator charging up the batteryGet this if you have problems starting up your car or bike and don't know why. it will point out for you if you need a new battery or you need to take your car or bike to the mechanic .PsIf it tells you ur battery is bad try a good battery charger (I have the optimate 6) it will really charge it up to tell you to change it and get a new one