Thanks !!
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tail light modulator
- Thread starter Mikey
- Start date
Thanks !!
The first modulator I used was on my 1979 GS850G when I took my post-graduation trip to California in 1981. I had been navigating LA traffic for a day or two and had experienced a couple of OMFG moments with cagers - so I stopped in to a big Suzuki dealership in Long Beach to get an oil change (and an underwear change as I recall it) and to have a MARTEK electronic ignition system installed on the '850 (the first year 1979 bikes still had a double points set-up and kick starter - which I never had to use).
I found the headlight modulator unit on-sale in the bike dealership accessories rack. It was called a Q-Switch and it was housed in a little metal box that you glued onto the front-side of the instrument cluster. It only worked on the headlight (pulsing from low to high-beam at about 4 Hz). I think it cost about $25 (which was no small amount of money in those days) but I had just been pretty badly shaken up and so I sprung for it installed it myself in the parking lot of the dealership. BTW: the Q-Switch is no longer sold (I just checked) but there are now tons of these types of units for sale from all kinds of suppliers.
NOTE: despite what many people will tell you (including some LEOs), headlight modulators are completely legal in every US State and every Canadian province and if anyone doesn't believe me - check FMVSS-108 in the US and CMVSS-108 in Canada and search for "modulators".
Anyhow, back to 1981 - within 5 minutes of setting out from the Suzuki dealership in Long Beach CA, I noticed that people would come up to a stop sign or a traffic signal and hit their brakes abruptly and stare as I road on by.
I don't think I have ever had a close-call again on a modulator equipped bike and I have had a modulator on nearly all of my bikes (head and taillights) ever since. I am still a cautious (i.e. slow...) rider but I am also convinced that it makes riding safer because people see me and, while they may wonder what the heck I am (cop, ambulance, who knows...?), it makes them stop and think before they barge out in front of me in their black highly polished phone-yakking BMW 3-Series with the loud music and dingly-balls hanging from the mirror (DAMHIK).
These modulator units are small, they weight nothing, they are dead easy to install and I have never had one fail in 40 years of using them - and they are far cheaper and a lot more fun that spending the rest of one's life in a wheelchair - or dead.
Pete
I found the headlight modulator unit on-sale in the bike dealership accessories rack. It was called a Q-Switch and it was housed in a little metal box that you glued onto the front-side of the instrument cluster. It only worked on the headlight (pulsing from low to high-beam at about 4 Hz). I think it cost about $25 (which was no small amount of money in those days) but I had just been pretty badly shaken up and so I sprung for it installed it myself in the parking lot of the dealership. BTW: the Q-Switch is no longer sold (I just checked) but there are now tons of these types of units for sale from all kinds of suppliers.
NOTE: despite what many people will tell you (including some LEOs), headlight modulators are completely legal in every US State and every Canadian province and if anyone doesn't believe me - check FMVSS-108 in the US and CMVSS-108 in Canada and search for "modulators".
Anyhow, back to 1981 - within 5 minutes of setting out from the Suzuki dealership in Long Beach CA, I noticed that people would come up to a stop sign or a traffic signal and hit their brakes abruptly and stare as I road on by.
I don't think I have ever had a close-call again on a modulator equipped bike and I have had a modulator on nearly all of my bikes (head and taillights) ever since. I am still a cautious (i.e. slow...) rider but I am also convinced that it makes riding safer because people see me and, while they may wonder what the heck I am (cop, ambulance, who knows...?), it makes them stop and think before they barge out in front of me in their black highly polished phone-yakking BMW 3-Series with the loud music and dingly-balls hanging from the mirror (DAMHIK).
These modulator units are small, they weight nothing, they are dead easy to install and I have never had one fail in 40 years of using them - and they are far cheaper and a lot more fun that spending the rest of one's life in a wheelchair - or dead.
Pete
Well ya got me thinking again(ouch)
Does the headlight modulator work by going from high beam to low beam ?
"allows motorcycle headlight modulation systems all 50 states provided they comply with the standards set forth in this section."
Just had to check and your advice is spot on!!
Bike web (or some other website) suggest you print out and carry on the bike the regulations
Not a bad idea if your in the middle of nowhere
I already have a copy laminated, of a MN (whatever it's called) stating that you can go foreword through a red light if you have been waiting way too long ) some traffic lights won't sense the weight of the bike crossing over their sensors
Yes - kind of.
According to the CVMSS- and FMVSS-108 specs (they are identical except for the spelling of words like colours - and the Canadian spec says "please" a few more times...
), modulators go from low to <I think> about 70-80% of high beam power at a specific frequency, which as I recall it is 4 Hz or 4 times/second. This frequency has been found to attract the attention of humans and animals - but not trigger epileptic seizures or cause people's skin to turn orange and their ethics and sense of reason to fail.If you are already on high beam (
) then I believe it powers DOWN by about 70% also at 4 Hz. The visual effect is the same.During the day, if you want to de-activate the modulator, all you do is quickly move your headlight switch from low to high beam and back. Just a quick "blip" and the modulator will stop, until you move the switch again.
The modern systems (i.e. the ones that are compliant with CMVSS-108 and FMVSS-108) are required to be equipped with a photocell light sensor which defeats the system when it is dark - so it won't work at night. My old Q-Switch didn't have that feature and lemme tell ya...if someone was being a dick with their high-beams at night, a couple of seconds of Q-Switch settled their hash very smartly indeed.
Pete
I have to dig into it a little but there might be a plug and play unit depending on what light bulb plug you haveYes - kind of.
According to the CVMSS- and FMVSS-108 specs (they are identical except for the spelling of words like colours - and the Canadian spec says "please" a few more times...
If you are already on high beam (
During the day, if you want to de-activate the modulator, all you do is quickly move your headlight switch from low to high beam and back. Just a quick "blip" and the modulator will stop, until you move the switch again.
The modern systems (i.e. the ones that are compliant with CMVSS-108 and FMVSS-108) are required to be equipped with a photocell light sensor which defeats the system when it is dark - so it won't work at night. My old Q-Switch didn't have that feature and lemme tell ya...if someone was being a dick with their high-beams at night, a couple of seconds of Q-Switch settled their hash very smartly indeed.
Pete
This looks like a good idea for the Yamaha and if it works out well for the Triumph I have as well
Thanks!
Yes - the modulator electronics module will have a socket for the specific harness and that little harness will go between the bikes headlight circuit wiring and the headlight bulb(s) itself. For "modern" bikes, the website will list a whole bunch of different wiring harnesses (one headlight/two headlights H4, H7 etc. etc.). For my XS650s and the BMW R100RS, I just use the generic H4 harness.
The headlight units are actually dead easy to install because you simply:
- disconnect the existing headlight connector;
- plug the connector into the "male" pigtail on the modulator;
- plug the "female" modulator pigtail onto the bike's headlight;
- find a convenient place for the little photocell (it is about the size of the head of a wooden match) - where it can "see" daylight).
Pete
Here is a pretty good video of both a head and taillight modulator working.
That's what I need Pete
Thanks !!
I hope to have a pinball game sold here shortly, so money to spend
I got embroiled in a discussion about headlight modulators in another forum and so I thought I'd put people's minds at ease here too with a bit more specific information about these devices....
While there are a lot of urban legends about this matter (including tales about people being dazzled by headlight modulators), in fact, headlight modulators were, and are, legal in every Canadian province and US state.
The relevant regulations are:
Riders may wish to print this out and carry it on their bike in case you need to speak with a police officer about your modulator. The language in the US regulation is virtually identical to the Canadian standard and even the section numbers in the regulation are aligned between the two countries).
The major differences are in the spelling of words like "colour" and the fact that the Canadian standard uses the word "please" a bit more often.
All seriousness aside though, I have carried this document with me on all of my bike travels for many years, but I have never been stopped by the police so I have never had to use it.
In conclusion, if these devices keep me out of a wheelchair or a coffin for a few years longer, then I am good with them.
Pete
While there are a lot of urban legends about this matter (including tales about people being dazzled by headlight modulators), in fact, headlight modulators were, and are, legal in every Canadian province and US state.
The relevant regulations are:
- in Canada: CMVSS 108 (Canadian Motor Vehicle Safety Standard) CMVSS 108 §7.9.4 which is on page 42 of the standard;
- in the United States: FMVSS 108 (Federal Motor Vehicle Safety Standard 108) 49 CFR Part 571.108 §7.9.4.
Riders may wish to print this out and carry it on their bike in case you need to speak with a police officer about your modulator. The language in the US regulation is virtually identical to the Canadian standard and even the section numbers in the regulation are aligned between the two countries).
The major differences are in the spelling of words like "colour" and the fact that the Canadian standard uses the word "please" a bit more often.
All seriousness aside though, I have carried this document with me on all of my bike travels for many years, but I have never been stopped by the police so I have never had to use it.
In conclusion, if these devices keep me out of a wheelchair or a coffin for a few years longer, then I am good with them.
Pete
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Good work Pete. Here's the US 49 CFR text.
49 CFR 571.108 S10.17.5
Motorcycle headlamp modulation system. A headlamp on a motorcycle may be activated to modulate either the upper beam or the lower beam from its maximum intensity to a lesser intensity, provided that:
S10.17.5.1 Modulation.
(a) The rate of modulation must be 240 ±40 cycles per minute.
(b) The headlamp must be operated at maximum power for 50 to 70 percent of each cycle.
(c) The lowest intensity at any test point must be not less than 17 percent of the maximum intensity measured at the same point.
(d) The modulator switch must be wired in the power lead of the beam filament being modulated and not in the ground side of the circuit.
(e) Means must be provided so that both the lower beam and upper beam remain operable in the event of a modulator failure.
(f) The system must include a sensor mounted with the axis of its sensing element perpendicular to a horizontal plane. Headlamp modulation must cease whenever the level of light emitted by a tungsten filament light operating at 3000° Kelvin is either less than 270 lux of direct light for upward pointing sensors or less than 60 lux of reflected light for downward pointing sensors. The light is measured by a silicon cell type light meter that is located at the sensor and pointing in the same direction as the sensor. A Kodak Gray Card (Kodak R-27) is placed at ground level to simulate the road surface in testing downward pointing sensors.
(g) When tested in accordance with the test profile shown in Figure 9, the voltage drop across the modulator when the lamp is on at all test conditions for 12 volt systems and 6 volt systems must not be greater than 0.45 volt. The modulator must meet all the provisions of the standard after completion of the test profile shown in Figure 9.
(h) Means must be provided so that both the lower and upper beam function at design voltage when the headlamp control switch is in either the lower or upper beam position when the modulator is off.
https://www.ecfr.gov/current/title-...-V/part-571#p-571.108(S10.)(S10.17)(S10.17.5)
49 CFR 571.108 S10.17.5
Motorcycle headlamp modulation system. A headlamp on a motorcycle may be activated to modulate either the upper beam or the lower beam from its maximum intensity to a lesser intensity, provided that:
S10.17.5.1 Modulation.
(a) The rate of modulation must be 240 ±40 cycles per minute.
(b) The headlamp must be operated at maximum power for 50 to 70 percent of each cycle.
(c) The lowest intensity at any test point must be not less than 17 percent of the maximum intensity measured at the same point.
(d) The modulator switch must be wired in the power lead of the beam filament being modulated and not in the ground side of the circuit.
(e) Means must be provided so that both the lower beam and upper beam remain operable in the event of a modulator failure.
(f) The system must include a sensor mounted with the axis of its sensing element perpendicular to a horizontal plane. Headlamp modulation must cease whenever the level of light emitted by a tungsten filament light operating at 3000° Kelvin is either less than 270 lux of direct light for upward pointing sensors or less than 60 lux of reflected light for downward pointing sensors. The light is measured by a silicon cell type light meter that is located at the sensor and pointing in the same direction as the sensor. A Kodak Gray Card (Kodak R-27) is placed at ground level to simulate the road surface in testing downward pointing sensors.
(g) When tested in accordance with the test profile shown in Figure 9, the voltage drop across the modulator when the lamp is on at all test conditions for 12 volt systems and 6 volt systems must not be greater than 0.45 volt. The modulator must meet all the provisions of the standard after completion of the test profile shown in Figure 9.
(h) Means must be provided so that both the lower and upper beam function at design voltage when the headlamp control switch is in either the lower or upper beam position when the modulator is off.
https://www.ecfr.gov/current/title-...-V/part-571#p-571.108(S10.)(S10.17)(S10.17.5)
Pete what are the approx dimensions of the headlight modulator? Will if fit inside the already cramped headlight bucket? Best place to buy for a Canuck?I got embroiled in a discussion about headlight modulators in another forum and so I thought I'd put people's minds at ease here too with a bit more specific information about these devices....
While there are a lot of urban legends about this matter (including tales about people being dazzled by headlight modulators), in fact, headlight modulators were, and are, legal in every Canadian province and US state.
The relevant regulations are:
I have attached an excerpt of the CMVSS 108 document showing the relevant language from page 42 of the standard.
- in Canada: CMVSS 108 (Canadian Motor Vehicle Safety Standard) CMVSS 108 §7.9.4 which is on page 42 of the standard;
- in the United States: FMVSS 108 (Federal Motor Vehicle Safety Standard 108) 49 CFR Part 571.108 §7.9.4.
Riders may wish to print this out and carry it on their bike in case you need to speak with a police officer about your modulator. The language in the US regulation is virtually identical to the Canadian standard and even the section numbers in the regulation are aligned between the two countries).
The major differences are in the spelling of words like "colour" and the fact that the Canadian standard uses the word "please" a bit more often.
All seriousness aside though, I have carried this document with me on all of my bike travels for many years, but I have never been stopped by the police so I have never had to use it.
In conclusion, if these devices keep me out of a wheelchair or a coffin for a few years longer, then I am good with them.
Pete
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There is no way would it fit inside an XS650 headlight bucket. I have my headlight module mounted with double-sided tape on the frame just behind the steering stem tube and it is unobtrusive there.
I think the dimensions are given on the Signal Dynamics website. I'd guess the headlight modulator unit is about 2-1/4" long x 1.5/8" wide x 5/8" thick - not large, but much too big for the headlight bucket. On the BMW R100RS, I have it mounted inside the fairing and again, it isn't noticeable. The slight issue is that you might thread the wiring into and back out of the harness to connect it to the module.
The taillight modulator is about the same size but it only has two wires. You simply install it in series in the brake light power circuit.
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Pete did you put the module in the headlight bucket
I guess I should read all the comments first
Did you have to cut the wires so the plug could be placed outside the bucket
