Modern Vespa

Please help with some data. Thanks!

We're investigating a problem with the comagination headlight modulator as detailed here: Head light modulator - still the only one
Although it modulates fine at idle, as your speed/voltage increase, the modulation stops. You wouldn't notice this unless you were looking carefully (say, by tailing a black Suburban or something with lots of chrome). Watch the flashing rate, does it vary? Even at idle, the difference between idle and slight throttle is visible.

For the people answering "No" I ask that you are certain that you don't have the issue. I didn't think I did either until I took a closer look

I have the Comagination headlight modulator but haven't installed it yet. I'm waiting to see what the resolution to this problem will be.

I ordered it originally for my Buddy but it didn't work there because as I found out later the voltage to the headlight is AC. The Comagination taillight modulator works great on the Buddy though.

I purchased the Comagination headlight modulator and the brake light modulator. My GTS is a 2007 with a manufacture date of July 2007. It has a little over 3000 miles on it. I installed the headlight modulator about a week ago. It does have the issue discussed here.

what is it and why do i need one

Gotta love polls!

OK, so if I believe the numbers above, around 50% of GTS owners have a bad alternator. Let's hear build dates for the ones that are having the issue.

built July 2008: '09 GTS 250 Super, not working.

I have an 06 GT200 and have no problem with the headlight modulator. I bought it when that thread came up a few weeks ago and since installing it the number of pulling out in front of me (I assume because they did not seem me) has dropped by 90% or more. Absolutely fantastic. [not exactly on topic, but wanted to emphasize that these things are great when they work]

My build date is 07/06. 1600 miles on mine.

GTS no problem. Build date 02/08

So is this working fine on the LX150?

Works perfectly well on mine!

Thanks! I am strongly considering getting one for safety. I see cagers inching out on the cross streets and I get nervous. How difficult is it to install the Comagination model?

Very, very easy. You have to remove the headlight plastic from the front, and making sure that you don't break the two tabs on the side is the hardest part. Three screws, and then it is simply a matter of unplugging the wire into the back of the headlight bulb, and plugging in the modulator unit, and running the light sensor to the outside (such as up and through the rubber grommet at the mirror stem). Very, very easy.

There's been a few write ups on how to do this, with pictures. I think that addicted posted one for the et4 (try searching for that).

Should I upgrade my bulb to something brighter while I am at it? Nothing HID, but is there possibly a higher wattage H4 bulb that you could recommend to go with the modulator?

Why is this problem only occurring in GTS models?

Noticed that as of this date, nobody answered your query. A "headlight modulator" will operate the headlight so that it appears to "flicker" to someone looking at it. Instead of a constant, steady beam, it appears to dim and brighten slightly, thereby drawing attention to the "flicker". It is one of the best safety devices for any motorcycle. In most places, it is illegal for the modulator to function after dusk and before dawn, hence the light sensor having to be run up to the mirror rubber.

It goes hand-in-hand with a brake light modulator, which when either brake lever is applied, the rear brake light will go on and off for a set number of set times before remaining steady on. Amount of blinks is determined by local state law. Again, it is to draw the attention of following automobiles, signaling them when you have applied your brakes. You don't want a car running up your back end.

Hopes this help.

It looks that way, but I don't think you could draw that as a proven scientific experiment. Or based on the data in the poll so far.

You are allowed to say you haven't gotten a poster yet on a non GTS who had problems.

IF someone said they had the problem on an LX150 than you could conclude it happens on at least some LX150.

Absence of data does not prove a negative result. Sorry, I used to be an engineer, although I try not to be these days.

2007 gts, bought Oct 06.
Comagination installed in 2006.
Modulation rate increases with rpm but is still a visible flicker at 85mph indicated.
Mileage now 23K and still working (which I cannot say about their brake light modulator).

So windbreaker, do you consider yours working properly or not?

This post was not quite
What we were hoping to see
Try again, perhaps?