Preventing Headlamp Bulb Breakage

Bruce Miller 2013

I forewarn the reader, the idea I am about to present may be nothing more than a groundless myth, a solution in search of a problem.

The problem, if it is a problem and not simply a matter of coincidence, is that of headlamp bulbs (446) shattering after being installed on a vintage Triumph motorcycle.

Did anyone's ears perk up out there?

Specifically, in the past, after replacing a headlamp bulb on the Bonnie, a new bulb frequently broke or separated from its base within a short time. This might happen to a couple of bulbs, one after the other.

Both are true, that a) Quebec paved roads are notoriously rough, and b) vintage stuff occasionally vibrates.

Perhaps with that in mind, although I'm not really sure how the idea came to me, but once, out of frustration at losing several bulbs one after the other, before I installed the next bulb, I dabbed a bit of grease onto the base's two contacts.

Result? End of losing streak. The bulb lasted as long as most bulbs do before they burn out or break one of their filaments, but neither the bulb's glass nor base broke during the time it was installed.

In my experience, no bulb whose contacts I greased before installing them has ever broken or come loose from its base.

I might be the guy snapping his fingers to keep away the elephants, but if you ever have a problem with breaking headlamp bulbs, try putting a small dab of general purpose grease on the contacts before inserting the bulb into the socket.

Snap..... snap...... snap

Bardfark Dungwall on Testing the 446 motorcycle headlamp bulb

And now, I'm told that Bardfark Dungwall, motorcycle mechanic extraordinaire, would like to add a few words concerning testing methodologies for the 446 motorcycle headlamp bulb. Take it away, Bardfark...

Ok. Yeah, right. Many times mates has said to me, "Barfark," they sez, "Barfark, how can I tell if my 446 headlight bulb is good or not?"

Well now, I tells 'em. That might seems what like a stupid question, but generally speaking I just eyeballs 'em, the bulbs, what I mean.

Take a squiz at the 446s down under.

You should see that the left one might be bad, the right one might be good, and the middle one might have been on the workbench when I was spray painting the cracks in my helmet's chin strap.

Or, it's maybe definitly bad. Your call.

Uh. Yeah, right. Thanks very much for that, Bardfark.

Just a few seconds left, I should tell the reader audience that an expert panel previously determined that all the bulbs illustrated are, indeed, bad.

You out there - you've got an ohmmeter, right? Or a continuity checker? If not, get on down to your hardware or auto parts store.

And don't forget to put a little grease on those headlamp bulb contacts.