Headlamp brightness

Dan79 · Scooby Slapper Joined: 26 Nov 2009 Karma :

Since my RXS100 died in the Spring I've reverted to using my 1984 Honda Magna for all my riding, including now the dark evening commutes.

I am wondering if something may have deteriorated in the performance of the dipped headlamp as I am finding that I don't like to exceed 60mph on unlit dual carriageways with good white lines, and quite a lot less on unlit single carriageways, as the headlamp simply doesn't illuminate enough of the road ahead - the light is the limiting factor on my speed at night. The difference between the dipped beam and main beam seems rather a lot - but both dipped beam and main beam have the same white quality of light.

(It's not my eyes - I have no trouble with the dipped beams when driving our Peugeot 107 in the dark).

I've taken the lamp apart and can see nothing obviously amiss, all the parts are present and correct, nothing is corroded, the lens isn't clouded, and the bulb is the correct rating for the lens.

Has my 3 years of winter riding using the RXS100, whose headlight was simply appalling, lead me to the false belief that my Magna used to have really a good headlamp (I never really used to use it for much night riding, particularly not in wet and overcast conditions) ? Is it realistic to expect the headlamp of a bike that age to be as good as those of a modern car? Or is there something else that I should be checking with wiring or suchlike ?
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Previous bikes - 1984 Honda VF500 (FII) Interceptor and 1990 Yamaha RXS100
Current bikes - 1984 Honda VF500 (V30) Magna

kramdra · World Chat Champion Joined: 28 Oct 2010 Karma :

Bezzer · World Chat Champion Joined: 14 Apr 2005 Karma :

Something of that age will never match a modern car headlight and most standard bike lights are crap in the wet because of all the reflections. Worth checking the voltage you get at the bulb holder on main and dip to see if it's getting decent volts. Some bikes can lose a fair bit because of old and/or standard small gauge wires, rewiring with new heavier gauge stuff can improve it a fair bit by helping to limit voltage drop. Modern better bulbs can also help.
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I used to be indecisive but now I'm not quite so sure.

Kickstart · The Oracle Joined: 04 Feb 2002 Karma :

Hi

To follow up Bezzers comment, if you do rewire the headlight circuit then it might be worth using a relay taking power directly from the battery, while the headlight switch wiring is just used to trigger the relay.

As switches age they can cause problems. And with most bikes (and a lot of older cars) pulling all the headlight power through the switch the contacts do suffer.

All the best

Keith
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Teflon-Mike · tl;dr Joined: 01 Jun 2010 Karma :

Dan79 · Scooby Slapper Joined: 26 Nov 2009 Karma :

Thanks for all the suggestions - will check these at some point.

It is a US import, a VF500 so the picture you posted Teflon Mike looks spot on. Yes the dipped beam is a running daytime lamp as well, so there is no off-switch separate from the ignition switch and therefore the only part of the headlamp that the rider can control is the switch to turn the main beam on or off. I don't think it has a left dip headlamp - as best i can tell, it is of the straight-ahead sort.

I did replace the ignition barrel about a year ago - might that be relevant to this issue?
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Previous bikes - 1984 Honda VF500 (FII) Interceptor and 1990 Yamaha RXS100
Current bikes - 1984 Honda VF500 (V30) Magna