Lighting Upgrade Questions

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Jeff in W.C.
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Lighting Upgrade Questions

Post by Jeff in W.C. »

I’m in the middle of a mechanical refresh on my ’88 R100 RT and I’m waiting for my drive shaft to be rebuilt. While I’m waiting, I’ve done what I can, but I’m now thinking of lighting upgrades. Specifically, upgrading to LED lights. Has anyone found a good LED replacement bulb for the turn indicators? What about an LED H4 replacement bulb for the headlight? Has only tried Motorrad Elektrik complete replacements reflector/bulb? http://www.motoelekt.com/lighting.htm With regards to the taillight, I'm leaning towards the LED one sold my Motorrad Elektrik.

I know this topic has been discussed, but I couldn't find a recent thread.
Jeff in W.C.
1988 R100 RT
2018 R1200 GS
"I've got my motorcycle jacket, but I'm walking all the time." Joe Strummer/Clash
Rob Frankham
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Re: Lighting Upgrade Questions

Post by Rob Frankham »

On LED indicator bulbs...

The issue with using LED bulbs in indicators is that the stock indicator relay (and most others not specifically designed for LED bulbs) will not work with them. The indicator relay actually requires a load equivalent to 2 x 21w bulbs and one 3w bulb (or thereabouts) to make it flash at the right rate. To put this in perspective, a typical LED bulb equivalent to a 21W filament bulb might have an actual rating of 1.5W.

It is worth considering why you wish to change the bulb to LED. This is normally one or more of three reasons:

a) To increase the light output.

b) To reduce the current consumption and

c) To make the lamp more reliable.

In practice, there are a number of ways to achieve LED indicator bulbs...

1) Wire a resistor in parallel with the LED lamp to make the current consumption the same as with a filament bulb. This allows the stock relay to work correctly but needless to say, doesn't fulfull aim B above. It also means that you have to find room for two fairly large resistors that may get hot. Proprietory resistors are available for this purpose.

2) Source specialised LED bulbs that are advertised to work with a stock relay. In practice, they do the same as (1) above just in one package, You still won't reduce the current consumption.

3) Use a custom made set including lamps and replacement relay which does reduce the current but tends to be costly.

So far, I've only mentioned aim B... reducing the current consumption... and I would comment that, since indicators are a transient load, (i.e. only on for a small percentage of the time and intermittently at that), reducing current consumption isn't anywhere near as important as reducing current in - say - a headlamp.

Aim A, increasing light output, is a bit hit and miss. Most LEDs offered for this use have a rating which quotes there equivalence to a filament bulb (i.e. in this case, 21W). This is actually saying that the light output is equivalent to that from a 21W filament bulb. It follows, therefore, that unless you source a LED lamp with a quoted rating more than 21W, you can't expect to get any real increase in overall light output. Where a LED scores over filament lamps is that the light output is concentrated over a limited area of the spectrum. To put it another way, you can tailor the light output to be the colour you actually want. Ideally, to get a real improvement in light output you need a LED that emits amber light (if that's the colour of indicators in your area).

As to aim C... LEDs do last a lot longer than filament bulbs in general but they don't last for ever, They do blow and, over an extended period, they also lose efficiency so a change to LED lamps isn't a once and for ever change. This isn't really a great consideration provided you use easily available items that can be replaced but, to mey mind, it is a good reason to avoid sets that use bespoke and exotic components which will be difficult to source in the case of a failure.

Whether LED indicators are worth bothering with is something I'll leave entirely up to you but the assumption that LED is necessarily better is a matter that bears some thought.

Rob
Last edited by Rob Frankham on Sun Apr 09, 2023 6:15 am, edited 1 time in total.
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Jeff in W.C.
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Re: Lighting Upgrade Questions

Post by Jeff in W.C. »

Thanks Rob. My goal is to have an increase in light output, or option a. I'm not really worried about current consumption and longevity. Some searching on Amazon indicated "plug in play" direct LED replacements for relatively low cost. Since they're not that expensive ($20 for a headlight and $20 for two indicator bulbs), I may take gamble and see how they work, but I haven't decided yet.
Jeff in W.C.
1988 R100 RT
2018 R1200 GS
"I've got my motorcycle jacket, but I'm walking all the time." Joe Strummer/Clash
Rob Frankham
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Re: Lighting Upgrade Questions

Post by Rob Frankham »

Sounds good... just make sure the LED indicator bulbs you source will work with the stock relay...

Rob
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Tom H Ca
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Re: Lighting Upgrade Questions

Post by Tom H Ca »

On my '70's bikes I changed out the tail/brake light with LEDs. 1157 type bulb. Much brighter than a regular 1157.

On my '07 HD, I made the rear turn signals work as brake and tail with a module that plugs into the tail light wiring harness. Added LED to the turn signals. All went fine until I added LED to the front turns. No workie, bummer. Removed fronts and all good again. I was all set to replace the flasher unit, but HD doesn't use one, it's built into a module. Could have added resistors, didn't want to mess with that.

On my '62 F100 I added LED brake/tail lights and front turn signals. Signals wouldn't work with the 60 year old flasher. Bought a LED compatible electronic flasher for under $10 usd. All good and now the lights are nice and bright.

If you want, I can give you the info on the bulbs I'm using. A pack of 4 is under $20 usd from Amazon.

As mentioned, get a bulb color that matches the lens. Red with red, amber with amber.

Headlight bulbs are a different story. Many are good, but the reflector in the headlight housing is what make one better than another. The bulbs have different designs that work better with one reflector than anther. Probably the best option is to get one that is a sealed unit instead of just a bulb. No recommendations for a good one.

Hope this helps,
Tom
'73 R75/5
'70 Guzzi Ambo 750
'72 Guzzi Eldo 850
'04 Guzzi California EVT
'07 HD Dyna Street Bob
'53 Triumph 6T (To be restored one day)

Tom
jackonz
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Re: Lighting Upgrade Questions

Post by jackonz »

I was going to put LED lights on my R80 during my rebuild but ran in to legal issues with this, here in NZ if the headlight assembly was designed for say a H4 lamp then that is all you can fit a H4, you can change it to a full assembly made and designed as a LED headlight but it must have a euro compliance cert or equivalent certification.

The reason I was going to do it was here in NZ you have to have your headlights on on a motorcycle or have daylight running lights fitted, so I went the daylight runners way with LED lights, as a matter of interest if these or NOT factory fitted then when the headlight is turned on the daylight runners must be turned off automatically.

As for LED indicators Rob is correct, however I have now been able to source a flasher unit in NZ that will work with either LED or incandescent lamps and no need for resistors at all so you can fit them to your existing indicator assemblies.
Phil J

Nelson NZ.
Rob
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Re: Lighting Upgrade Questions

Post by Rob »

I absolutely loved the taillight assembly from Motorrad Elektrik. Especially after my original bulb and socket began flaking out from vibration.
Rob V
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SteveD
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Re: Lighting Upgrade Questions

Post by SteveD »

Rob wrote: Wed Apr 12, 2023 11:03 am I absolutely loved the taillight assembly from Motorrad Elektrik. Especially after my original bulb and socket began flaking out from vibration.
I found one of the leads fell off. It was in a difficult position to repair but I managed it. Important to check there's no strain at the connection when fitting.

RT lights like this would be a bonus I reckon!
R100RT lights.jpg
R100RT lights.jpg (118.5 KiB) Viewed 1196 times
R100RT-Lighting.jpg
R100RT-Lighting.jpg (100.47 KiB) Viewed 1196 times
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
2006 K1200R.
1994 R1100GS.
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