Multimeter 101: Test your Battery, Coil & Stator

[Greasesgarage]

We hear it all the time from people on the forums and other chopper guys in the wild…BUY A MULTIMETER.

So you pony up the $7 and grab one from harbor freight, but NOW WHAT?

In UNDER 7 MINUTES I’ll show you three SIMPLE tests you can do on your bike to make sure your charging system is ready to rock and roll this season.


$7 Dollars 💵


7:00 Minutes ⏰


Hours of frustration and tow fees saved 🙏🏼


Enjoy (and SUBSCRIBE)

[TriNortchopz]

A good intro / refresher for meter use; a 7-minute investment.


use you multimeter to test these:

Motorcycle Charging System Diagnosis Checks


"There are three main sections to the charging system on most bikes (excluding the wiring in between). Those are the Battery, Regulator/Rectifier (R/R) and the Stator...

https://www.aberdeenbikers.co.uk/motorcycle-charging-system-diagnosis-checks/

here is an electrical reference for the Panheads and some Flathead; a chance to use your meter skills:

Panhead and Flathead site

Knowledge Base (Forum Archive)

Electrical system: 542 topics
Specific subjects: Generator

https://www.hydra-glide.net/kb/kb_toc6.php

and more from there;

Documentation / Information
includes wiring diagrams and Delco-Remy articles for generators, regulators and more.

https://www.hydra-glide.net/kb/kb_index.php

[TriNortchopz]

and things are a bit different with the old classic British bikes - positive ground and Lucas electrics...you know the jokes about Lucas, right? Well think positive...ground that is.

Technical Support
LUCAS ALTERNATOR TIPS

"The alternator system fitted to British bikes from the 1960 season is a very clever way to extract the most electrical power from the least amount of space while not having to completely redesign the primary drive. BSA fitted alternators to the B33 singles toward the end of production and to all machines in the range after 1962.Triumph used an alternator on the 5T for 1954 on and the Thunderbird from 1956. All Triumph models used alternators from 1960 on..."

https://www.jrcengineering.com/technical-support/lucas-alternator-tips/

Your Bike’s Charging System – Regulator/Rectifiers

"This article sets out to provide some information around regulator/rectifier options for British bikes – where possible I have tried to break things down to make them simpler to understand, and explain terminology... We are discussing charging systems that are built around permanent magnet alternators, so this does not cover alternators with field wound rotors or bikes that use a dynamo..."

https://granttiller.com/regulator-rectifiers-alternators

LUCAS Service Manual

https://jerrydoe.com/norton_pdf/Lucas-service.pdf

Lucas Energy Transfer (ET) ignition unraveled
"Lucas AC or Energy transfer ignition was used on many competition motorcycles among them the BSA B44E, B50MX and Triumph models T20M Cub, T100C , TR6C and most famously the T120C or TT Special. Many of these bikes have been converted to DC coil ignition but if you are fortunate enough to get a bike still equipped with ET ignition and it doesn’t start of runs poorly don’t despair, there is hope, so don’t phone home just yet!

First off this is not an in depth discussion of theory or an engineers description of how this works, it is a practical guide gleaned from years experience with this mostly reliable ignition system..."

https://www.jrcengineering.com/technical-support/electrical-tech/lucas-et-ignition-unraveled/

Electrical guide index
A selection of electrical ‘how to’ guides
" I thought it might be useful to put together a collection of idiot-proof guides to some common tasks with lots of photos and which take you through step-by-step. No doubt these might quite often state the obvious to the experienced classic bike owner, but when it’s your first time and your learning (and desperate not to do something wrong and ruin your new pride and joy!) then for me, a step-by-step hold your hand guide would be quite useful. I hope you’ll think so too!..."

https://www.matchlessclueless.com/electrical/

British and a whole lot from the rising sun:
Rex’s Technical Support
"Welcome to our technical help page where the latest versions of our fitting guides, testing procedures, wiring diagrams and other useful guides can be downloaded free of charge... Fitting and testing guides must be used in conjunction with the machine’s workshop manual, all work must be carried out by correctly trained and experienced persons using the specified tools and equipment..."

https://www.rexs-speedshop.com/rexs-technical-support/

[docmel]

and things are a bit different with the old classic British bikes - positive ground and Lucas electrics...you know the jokes about Lucas, right? Well think positive...ground that is.

Technical Support
LUCAS ALTERNATOR TIPS

"The alternator system fitted to British bikes from the 1960 season is a very clever way to extract the most electrical power from the least amount of space while not having to completely redesign the primary drive. BSA fitted alternators to the B33 singles toward the end of production and to all machines in the range after 1962.Triumph used an alternator on the 5T for 1954 on and the Thunderbird from 1956. All Triumph models used alternators from 1960 on..."

https://www.jrcengineering.com/technical-support/lucas-alternator-tips/

Your Bike’s Charging System – Regulator/Rectifiers

"This article sets out to provide some information around regulator/rectifier options for British bikes – where possible I have tried to break things down to make them simpler to understand, and explain terminology... We are discussing charging systems that are built around permanent magnet alternators, so this does not cover alternators with field wound rotors or bikes that use a dynamo..."

https://granttiller.com/regulator-rectifiers-alternators

LUCAS Service Manual

https://jerrydoe.com/norton_pdf/Lucas-service.pdf

Electrical guide index
A selection of electrical ‘how to’ guides
" I thought it might be useful to put together a collection of idiot-proof guides to some common tasks with lots of photos and which take you through step-by-step. No doubt these might quite often state the obvious to the experienced classic bike owner, but when it’s your first time and your learning (and desperate not to do something wrong and ruin your new pride and joy!) then for me, a step-by-step hold your hand guide would be quite useful. I hope you’ll think so too!..."

https://www.matchlessclueless.com/electrical/

British and a whole lot from the rising sun:
Rex’s Technical Support
"Welcome to our technical help page where the latest versions of our fitting guides, testing procedures, wiring diagrams and other useful guides can be downloaded free of charge... Fitting and testing guides must be used in conjunction with the machine’s workshop manual, all work must be carried out by correctly trained and experienced persons using the specified tools and equipment..."
https://www.rexs-speedshop.com/rexs-technical-support/

While I have found You Tube not exactly 100% the correct answer to many mech probs out there,most of the bike stuff (At least US stuff) is pretty solid: Lotsa questions asked on the forums here can be answered by cruising You tube

[drivermark]

TriNortchopz Thanks for all the links, good info, I used to just hate Lucas electrics when I had my Triumph-They didn't call him the Prince of Darkness for nothin'

[DustyDave]

TriNortchopz Thanks for all the links, good info, I used to just hate Lucas electrics when I had my Triumph-They didn't call him the Prince of Darkness for nothin'

I was riding next to a guy on a Triumph when his Zenner diode under the headlight vibrated off! While I was trying to get his attention he suddenly had his own smoke and light show melted most every wire off the silly thing by the time he got it pulled over.
Dusty

[TriNortchopz]

... he suddenly had his own smoke and light show melted most every wire off the silly thing by the time he got it pulled over.

The three-position Lucas switch--DIM, FLICKER and OFF.

The other three switch settings--SMOKE, SMOLDER and IGNITE!

and we know, Lucas is an acronym for Loose Unsoldered Connections and Splices....

[TriNortchopz]

Tips And Tech

Basic Electronic Troubleshooting

"If there’s one thing that confounds the average do-it-yourselfer, and quite a few professionals for that matter, it’s a motorcycle’s electrical system...

an electrical system can only function when three things are present:
First, we need a power source; in this case, it's the motorcycle's battery, and for convenience, we'll lump the source in with any necessary wiring and switches.
Second, is some sort of electrical load, for example a starter motor or light bulb, and last,
is a pathway to ground...
If one of those three components is damaged or missing, then our circuit is incomplete (or open), and can’t function...
a good percentage of electrical problems the average rider encounters are caused by something straightforward like a broken wire, bad ground or a failed component...

two basic test tools: a test light, and a DVOM or Digital Volt Ohm meter.

Of all the electrical troubleshooting tools available, nothing is as easy to use or as versatile as a plain old five-dollar test light.

A DVOM lets you measure things like AC and DC voltages, resistance, amperage, continuity... the older analog-style meters, using them on newer motorcycles isn’t a particularly good idea; analog meters tend to have high internal resistances, so they can be less than accurate, and I’ve also heard of them damaging sensitive computer-driven components...


All electrical troubleshooting needs to be performed as logically and systematically...
Think the problem through: did it start after some accessory or wiring modification was performed? Does the problem occur when the bike sits or after a period of heavy electrical use or under specific circumstances (like when you’re wearing a heated riding suit)?

use your shop manual; many contain step-by-step troubleshooting guides that will lead you more directly to the problem...

After not riding the bike for several weeks, you try to start it. The engine cranks slowly and fails to start, and after a few tries it gives up the ghost...
The first step is to charge the battery and retest it... at a fast idle: the voltage should read close to 14 to 14.5 volts.
If everything looks good on the meter, you need to ride more often...

https://www.motorcyclecruiser.com/basic-electronic-troubleshooting/