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Breva 11 headlight... again...

tobinh

Cruisin' Guzzisti
GT Famiglia
Joined
Oct 15, 2016
Messages
421
Location
Coquitlam, BC
Hi guys,

So, I've been pondering my headlight on the Breva for years now. I've even made several posts here! I know the proper solution is to replace the whole thing with a proper LED assembly like Todd sells here, but I just really like the appearance of the stock unit.

I've tried various bulbs with no effect... I'd still like to try some modern LED bulbs with the fans attached. I understand that there isn't room in the stock bucket, but it looks like there's room behind it - so I figure I'll just make an aluminum cover with appropriate clearance. I'm a machinist, so no problem there.

But, problem: before I buy proper quality bulbs from Cyclops via this site, I figured I'd try some cheapies that looked dimensionally close, just in case the reflector issue is as bad as people say it is. So I get them in, and nothing! They don't even turn on. I figure I have them backwards, but no.

So, question: is there any electrical reason these don't work? Or did I just go too cheap? People keep telling me LEDs won't work on this bike, but not why... I assumed it was just the size issue, but is there something else?

Thanks,
Tobin.
 
Have you seen this? https://www.guzzitech.com/forums/threads/headlight-conversion-for-the-1100-breva.18970/ That stock headlight is just junk and not worth trying to get good light from it.
I have, yea... I'm sure you're right. I think I'm just being stubborn at this point. I've had this dumb motorbike for so long now the looks of that weird headlight have been imprinted on my brain and I'm reluctant to change it.

I'm still confused as to why the bulbs didn't turn on at all though? Do you know of any reason inherent to the bike itself?
 
It should at least turn on.
I had an LED low beam in my 1200 Sport for a short time which is the same bucket as you have. At the time, I could not get a LED high beam which fit in the allotted space.

For me, the pattern was definitely not great and the light was worse (even though it appeared brighter).
In the end, the fan portion of the bulb melted. I expect I should not have put the cover back on the back of the light assembly as there was not enough air allowed in for the cooling fan to work properly.
 
It should at least turn on.
I had an LED low beam in my 1200 Sport for a short time which is the same bucket as you have. At the time, I could not get a LED high beam which fit in the allotted space.

For me, the pattern was definitely not great and the light was worse (even though it appeared brighter).
In the end, the fan portion of the bulb melted. I expect I should not have put the cover back on the back of the light assembly as there was not enough air allowed in for the cooling fan to work properly.
Great, thanks. I got the world's crappiest LED bulbs to prototype the cover I want to make, so that's likely the problem. It's just that I ran across various stories on the internet that made me wonder. Now I can forge ahead troubleshooting.

Thanks!
 
It should at least turn on.
I had an LED low beam in my 1200 Sport for a short time which is the same bucket as you have. At the time, I could not get a LED high beam which fit in the allotted space.

For me, the pattern was definitely not great and the light was worse (even though it appeared brighter).
In the end, the fan portion of the bulb melted. I expect I should not have put the cover back on the back of the light assembly as there was not enough air allowed in for the cooling fan to work properly.
Turns out the sockets were just marginal, the same thing would have happened had I replaced with halogens. Pretty chintzy units for an OEM! Anyways I got both lights working, now I'm going to see if I can design a cover to go over the big heat sinks/fan units. It's possible there isn't enough room behind the bucket after all, I was in taking some rough measurements.

Will update for the ...uh, approximately zero other people who care about this.
 
I too had bad experience with the LED replacement bulbs. I replaced the low beam light with a LED one, I noticed the light output was bluer, but very little increase in brightness.

Then it blew, and I was in a small town without street lighting. Trying to ride with flashing the high been off & on trying not to offend other motorists was not fun,
 
I too had bad experience with the LED replacement bulbs. I replaced the low beam light with a LED one, I noticed the light output was bluer, but very little increase in brightness.

Then it blew, and I was in a small town without street lighting. Trying to ride with flashing the high been off & on trying not to offend other motorists was not fun,
Generally, when smart people say 'hey, I've already tried that, don't do make the same mistake again', I'm clever enough to listen.

In this case, I've decided to take (waste) the time to experiment a bit, in order to make said mistakes in a slightly different way.

Probably my experience will serve to help sell a few of the apparently excellent headlights offered here: https://gtmotocycles.com/collections/electronics
 
The H4v10ULTRALEDBULB that Todd is selling is a lot more substantial than the one I was using.

I was an early pioneer of the LED bulb, and I'm sure they have improved significantly since. Other than my V85 which has twin LED headlights as stock, the only other one I've upgraded so far, is my Griso 1200 which has a LED headlight designed for a Jeep.

Brilliant! (pun intended).
 
The H4v10ULTRALEDBULB that Todd is selling is a lot more substantial than the one I was using.

I was an early pioneer of the LED bulb, and I'm sure they have improved significantly since. Other than my V85 which has twin LED headlights as stock, the only other one I've upgraded so far, is my Griso 1200 which has a LED headlight designed for a Jeep.

Brilliant! (pun intended).
I guess this is my secret hope, a combination of new LED tech and my own custom designed / machined rear cover will give me a stock-looking headlight that actually works.
 
well, every decent high beam/H9/H11 LED bulb fouls the frame at the steer tube. I didn't realize it stuck out quite that far...

so I'm going either the relay route or making whole new headlight brackets/ears to space out the bucket .250" or so. honestly, I'm tempted to make a set, but it's a lot of work for possibly little gain.

so, probably going to wire in a relay and see how that goes.

I think I was getting 12.4V at the headlight socket when I tested it, it should be more than 13.5+V shouldn't it?
 
yea, but battery voltage while running should be around 13.7 right?

Not necessarily. A half flat battery will not have that high a voltage at its terminals (after all, it is a 12V battery). As the battery is charged the voltage will rise. If it is not rising, then check one of the main fuses hasn't blown.
 
Not necessarily. A half flat battery will not have that high a voltage at its terminals (after all, it is a 12V battery). As the battery is charged the voltage will rise. If it is not rising, then check one of the main fuses hasn't blown.
ah okay. I'll just check the voltage at the battery and then at the socket.

kind of academic, I'm pretty sure a relay is required, but I'll post the results.

thanks!
 
I'm not sure what you hope to achieve with a relay. The issue appears to be that your battery may not be getting charged.

You have checked the main fuses?
 
I too had bad experience with the LED replacement bulbs. I replaced the low beam light with a LED one, I noticed the light output was bluer, but very little increase in brightness.

Then it blew, and I was in a small town without street lighting. Trying to ride with flashing the high been off & on trying not to offend other motorists was not fun,
I had a burnout of the headlight wire harness (my story here) and had to ride ~130 km without any light in front. Not good. Managed to get back home just as night was about to fall...
 
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yea, but battery voltage while running should be around 13.7 right?
I can confirm. Took some measurements while fighting with the infamous Startus Interruptus. Some with multimeter, others with an oscilloscope. While max. voltage (instantaneous value) was 14.4V as it should be at the output of the generator - the voltage measured just the other day (when my headlight harness burnt up) at the battery terminals was 13.7 V (reading from the multimeter). Hope this helps.
 
General note about vehicle lights:
my uncle, who is a professor of physics, worked with lasers a lot and has superb knowledge in optical instruments and theory of optics gave me the following advice:
I asked if it would be a problem, to put an orange LED light in the indicator. He said it could work, but since the enclosure is made so that its surface is a matrix of small lenses and there is a curved mirror-like surface behind the bulb - it is important to have the source of light at the precise location for the optics to work as designed. If it is misaligned, the light could be diffused and the indicator could emit it in undesirable directions. The incandescent bulb is seated at such precise location in the indicator with the assumption the filament within the bulb itself will be at the (more or less) proper location as well. Then the optical arrangement works as expected.

So, I presume, it gets much worse (as far as optical properties are concerned) with larger lamps, such as the headlight. If you take a headlight which was designed for incandescent bulbs where filaments are expected to be at their designated locations for the mirror behind and (possibly?) the glass in front (or lens in high beam reflector) to do their jobs properly. H7, H4 or other LED-"bulbs" have rows of LED structures which cannot be located at the same place where the filament is in the incandescent equivalent (that is: in the centre of the bulb).
So, putting in such LED "bulbs" may produce suboptimal results. It is therefore much better to go for a completely new, LED-based headlight assembly. Hope this helps.
 
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