Dumb question alert... : where can I buy a voltmeter for my Harley? Recently moved back to home to Melbourne from Canada and have little idea which retailers would sell a voltmeter.

Imported the 1992 FXR back with me. Recently started getting interrmittent low voltage warnings/flashes on my Dakota digital gauge (new battery) only when bike at idle at a light (not at running speed or if I slightly up the rpm past 1000), indeed I think the low voltage flash (the gauge actually just flashes the words low volt) only appears sub-1000 rpm. I'm thinking it's about time I learned how to use a voltmeter (Dakota digital gauge went on fritz on me a few years ago (one before this one)), so I thought I'd get ahead if any potential problem. 

Any tips???

Seems there are two sizes of voltmeter, the smaller unit having a narrower range (ie. lower limit of 40ohm not 20) ? I'm thinking the smaller unit could be stowed in saddle bags easier, but does it have enough functionality for a charging system diagnosis on a hog?

For what we need to do on a Harley basically any multimeter will do the trick. You need a voltage range to check battery and charging etc - my unit has a 20volt range which is perfect for this. Plus an Ohmmeter to measure resistance and connections - again any basic multimeter will have the right ranges out of the box. Must admit i have NEVER carried one with me on a ride though.

That 40/20ohm thing is just the ranges.  The units still go from 1-40 or 0-20 ohms no problem - the range just lets you know the upper limit for that particular range setting.

Just go with the one you like the look of best....and then read the instructions if your a noob to these devices. They can look intimidating but are actually simple to use.

Tussuck, thanks for clarifying the ranges question for me. That helped a lot. I'm still considering a smaller voltmeter unit so I can pack it in the saddle bags, if only because if my ride has trouble it's always electrical something. At some stage I'll drop $1,000 to completely rewire the bike, maybe in February 2017 when it will be 25 years old!

thanks to all for taking the time to answer my dumb question. I'm slowly learning all the self-maintenance tasks after years of relying on twice-yearly service visits at Indy shops. I'm finding it quite satisfying, like finally getting the point of Zen and the Art of Motorcycle Maintenance. 

I have a small wallet sized one similar to this that i keep in the bike on the larger rides. handy and small, does all I need it to do.

FLH, I bought a small unit today (dial with digital readout) and, with the help of a few YouTube videos, successfully completed a charging test on my FXR. Battery and stator and stator plug passed. I was getting an intermittent low voltage warning from my Dakota digital gauge at idle, but it seems tweaking the battery leads and the stator plug solved that. Went for long run, including stopping to monitor idle, and no more low volt warning.

Moral of the story is that asking on hdforums where to get a multimeter, then buying a $20 multimeter from Bunnings, plus watching a few YouTube videos, saved me taking the bike to an Indy shop, probably leaving it there 2 days with all the transport back/back-there hassles, and paying $100 for a charging system diagnosis. To be told all checks out so just battery lead or stator plug loose. Or to be told I need a new stator (heh, report the most expensive fix is needed if the customer is an idiot?!).

Kiwidave, that's a great read! I bookmarked the blog. Though I know that packing the voltmeter in the saddlebags on trips will probably mean zero use until the one time it is needed and I forgot to change the battery.