How do modulators affect filament life? How friendly are they with LED headlights?
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tail light modulator
- Thread starter Mikey
- Start date
My tail light failed last week but fortunately my wife was following on her meteor and I replaced it at the next petrol station for $7 for two bulbs. Might last three months, actually bought a complete new tail light housing from the USA last year because mine was worn out where the bulb locates.
No - there are no wires to be cut at all. It is entirely a plug'n-play deal.
Basically, you buy the standard modulator "box" which has a proprietary 6-pin connector on a short pigtail and then you select the correct custom "bike" harness for your bike's headlight configuration and plug that harness into the pigtail (the website has a good photo of this - and it is very intuitive when you see it). Then you simply thread the two branches of the custom "bike" harness into the bucket. Each branch of the "bike" harness has a regular-sized headlight connector on it (one "male" and one "female"), so you do wind up with one extra headlight connector inside the already pretty full XS650 headlight bucket.
There are several different custom "bike" harnesses available from Signal Dynamics - but my bikes all use the simplest single H4 halogen harness. When I had the 2007 Honda ST1300 - which had two H4 headlights - I simply bought the twin H4 harness. The company website has a whole chart of harnesses and bikes to permit you to buy the correct one for most modern bikes - but the single H4 generic harness is almost certainly what most of us would use for a simple old bike like an XS650 or mid-80s BMW.
Anyhow, after mounting the module somewhere near the front of the bike (see the photos below) you unplug the headlight inside the bucket and insert the "male" version of the normal three-prong headlight connector that is mounted on one branch of the "bike" harness. This "male" connector plugs into the "female" headlight connector on the stock bike wiring harness and the "bike" harness goes back to the proprietary Signal Dynamics 6-pin connector near the modulator "box" (which is located outside of the headlight bucket). The other branch of the "bike" harness, which has the usual "female" headlight connector, plugs onto the backside of the headlight as usual.
Below are a photo of the modulator box mounted on the '78 XS650E Betty and another photo of the box mounted inside the fairing on the '83 BMW R100RS Gretel. The blue thingy in each photo is the proprietary 6-pin connector to which the "bike" harness is connected. I will do a better job of hiding the little modulator box in the spring (likely I'll just put a strip of electrical tape over the labels).
Yamaha XS650E mount >
BMW R100RS mount > 
You also need to mount the little photo-cell / light sensor that defeats the modulator when it is dark outside. I just made a little bracket out of sheet metal and mounted it to the handlebar mount on each bike. Here are photos of the sensors on each of the above bikes:
XS650E light sensor >
BMW R100RS light sensor > 
It may all sound complex - but it couldn't be simpler when you see it - although, as noted, getting the extra headlight connector inside the "too danged small" XS650 headlight bucket took a bit of body English and some use of the "extended vocabulary".
...and to answer Marty's question about filament life: I have had modulators on my bikes for years and have not had to replace a single headlight bulb on any of them. I put more than 45,000 km (about 25,000 miles) on the ST1300 and both headlights worked fine throughout and even on the XS650 - no replacement bulbs have been required.
On the matter of LED lights - I don't presently have any LED headlights on my bikes - but I have heard that the Signal Dynamics headlight modulator that I am running does not work with LEDs.
There are other modulators that are for use with LEDs however, so you'd need to search for one of those.
Pete
Basically, you buy the standard modulator "box" which has a proprietary 6-pin connector on a short pigtail and then you select the correct custom "bike" harness for your bike's headlight configuration and plug that harness into the pigtail (the website has a good photo of this - and it is very intuitive when you see it). Then you simply thread the two branches of the custom "bike" harness into the bucket. Each branch of the "bike" harness has a regular-sized headlight connector on it (one "male" and one "female"), so you do wind up with one extra headlight connector inside the already pretty full XS650 headlight bucket.
There are several different custom "bike" harnesses available from Signal Dynamics - but my bikes all use the simplest single H4 halogen harness. When I had the 2007 Honda ST1300 - which had two H4 headlights - I simply bought the twin H4 harness. The company website has a whole chart of harnesses and bikes to permit you to buy the correct one for most modern bikes - but the single H4 generic harness is almost certainly what most of us would use for a simple old bike like an XS650 or mid-80s BMW.
Anyhow, after mounting the module somewhere near the front of the bike (see the photos below) you unplug the headlight inside the bucket and insert the "male" version of the normal three-prong headlight connector that is mounted on one branch of the "bike" harness. This "male" connector plugs into the "female" headlight connector on the stock bike wiring harness and the "bike" harness goes back to the proprietary Signal Dynamics 6-pin connector near the modulator "box" (which is located outside of the headlight bucket). The other branch of the "bike" harness, which has the usual "female" headlight connector, plugs onto the backside of the headlight as usual.
Below are a photo of the modulator box mounted on the '78 XS650E Betty and another photo of the box mounted inside the fairing on the '83 BMW R100RS Gretel. The blue thingy in each photo is the proprietary 6-pin connector to which the "bike" harness is connected. I will do a better job of hiding the little modulator box in the spring (likely I'll just put a strip of electrical tape over the labels).
Yamaha XS650E mount >
BMW R100RS mount > You also need to mount the little photo-cell / light sensor that defeats the modulator when it is dark outside. I just made a little bracket out of sheet metal and mounted it to the handlebar mount on each bike. Here are photos of the sensors on each of the above bikes:
XS650E light sensor >
BMW R100RS light sensor > It may all sound complex - but it couldn't be simpler when you see it - although, as noted, getting the extra headlight connector inside the "too danged small" XS650 headlight bucket took a bit of body English and some use of the "extended vocabulary".
...and to answer Marty's question about filament life: I have had modulators on my bikes for years and have not had to replace a single headlight bulb on any of them. I put more than 45,000 km (about 25,000 miles) on the ST1300 and both headlights worked fine throughout and even on the XS650 - no replacement bulbs have been required.
On the matter of LED lights - I don't presently have any LED headlights on my bikes - but I have heard that the Signal Dynamics headlight modulator that I am running does not work with LEDs.
There are other modulators that are for use with LEDs however, so you'd need to search for one of those.
Pete
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I was thinking that you had to push the female connector somehow into the bucket and that couldn't happen
Jim, I bought a pair of these and a thought they’re supposed to be easy to install, but I can’t get mine to work. I disconnected the brake light wire under the seat and connected the red “in” wire to the “bike“ side of the disconnected harness. The “in” black wire was connected to ground. On the output side, the red wire was connected to the brake light bulb wire. Question is, where does the blank “out” wire go, to any ground? When it’s hooked up, my tester sees modulated voltage but the bulb doesn’t illuminate. I thought perhaps the black output wire was in the wrong place. Only other thing is I have a really weird looking LED bulb. Maybe it the devices don’t like each other. Any ideas?
The brake bulb has to go to ground through the controller for it to work.
Brake light power goes to the red V-in
Frame ground goes to Black V-in
Power to bulb comes from red out
Ground for bulb goes to black out
Both the power and ground must run through the box.
You can try just grounding both blacks to the frame and see what happens. Never tried it that way, but it's worth a shot before you start modding the taillight housing.
