Headlight Interference
#1
Thread Starter
Senior Member
Joined: Jul 2014
Posts: 323
Likes: 0
From: Western, MA
Bikes: 2016 Felt Z85 105, 2016 GT Grade Sora
Headlight Interference
Hello All,
Currently, i use a Cygolite Metro 300 for my commute however, it interferes with my bike Computer a Sigma Wireless with a cadence and speed sensor. i believe a BC16.12 if memory serves me right.
in any case, i was looking to upgrade my bike computer a Lezyne Super GPS. I'm happy with my light, i commuter mostly in the city and don't require much light but I've learned that this light produces RF interference (i think) and it blocks the signal from my sensors to my bike computer.
anyone have any ideas if i'll get the same issues with the light i have at present with a Lezyne super GPS or a Garmin 520?
or does anyone have any recommendation for a different USB rechargeable light that is comparable that will work without producing these side effects?
thanks in advance,
Currently, i use a Cygolite Metro 300 for my commute however, it interferes with my bike Computer a Sigma Wireless with a cadence and speed sensor. i believe a BC16.12 if memory serves me right.
in any case, i was looking to upgrade my bike computer a Lezyne Super GPS. I'm happy with my light, i commuter mostly in the city and don't require much light but I've learned that this light produces RF interference (i think) and it blocks the signal from my sensors to my bike computer.
anyone have any ideas if i'll get the same issues with the light i have at present with a Lezyne super GPS or a Garmin 520?
or does anyone have any recommendation for a different USB rechargeable light that is comparable that will work without producing these side effects?
thanks in advance,
#4
Sorry to hear of your trouble. I'm using a Cygolite Expilion 850 USB, which I love, and I just got my new Sigma BC 16.16 STS Wireless installed, but haven't yet had the chance to ride with it. I sure hope I don't have the same problem.
#5
Junior Member
Joined: Nov 2009
Posts: 180
Likes: 11
From: Taylor, MI
Bikes: 2008 Trek 2.1 WSD, 2010 Specialized Amira Elite, 2011 Trek Madone 5.2 WSD
It's kind of hit or miss with wireless computers and many of the higher powered lights. I have a cygolite metro 500 that interfered with two cateye strada wireless computers, but didn't bother a third one. I got a couple of new computers that use ant+ sensors and they work fine. Bluetooth sensors/computers should work fine as well.
good luck,
P2
good luck,
P2
__________________
2011 Trek Madone 5.2 WSD
2009 Trek 2.1 WSD
2011 Trek Madone 5.2 WSD
2009 Trek 2.1 WSD
#7
old fart

Joined: Dec 2007
Posts: 387
Likes: 6
From: PA-US
My 4 separate light systems cause no interference.
The enduro bike has a SP PD-8 dynamo and a B&M Lumotec IQ-X headlight + a B&M Secula Plus taillight.
The touring bike is also with a SP PD-8 dynamo, and a B&M IQ2 Luxos U headlight + a Toplight Line Brake Plus taillight.
The "shopping" townie & commuter uses an Alfine dynamo, and a B&M Lumotec IQ Cyo N Plus + Toplight Line Brake taillight.
The fixie uses a Fenix BC30R headlight, and a Hotshot blinkie.
All have/had wireless computers at one point of time or another, never noticed any interference.
The enduro bike has a SP PD-8 dynamo and a B&M Lumotec IQ-X headlight + a B&M Secula Plus taillight.
The touring bike is also with a SP PD-8 dynamo, and a B&M IQ2 Luxos U headlight + a Toplight Line Brake Plus taillight.
The "shopping" townie & commuter uses an Alfine dynamo, and a B&M Lumotec IQ Cyo N Plus + Toplight Line Brake taillight.
The fixie uses a Fenix BC30R headlight, and a Hotshot blinkie.
All have/had wireless computers at one point of time or another, never noticed any interference.
#8
Senior Member
Joined: Sep 2014
Posts: 92
Likes: 1
From: Findlay, OH
Bikes: 2014 Bianchi Sempre Pro, 1995 Bianchi Premio, 2014 Bianchi Pista Fixed Gear, 1994 Bianchi Timber Wolf
My Metro500 interfered with my Cateye Strada. After a little trial and error, I now have the light mounted underneath my handlebar and no longer have a problem. As it turns out, I like having the light a bit more hidden in this manner. I just bought a Polar M450 but have only had a chance to use it once. I have it on my road bike with a Dart200 light, and had no issues. I haven't tried it yet on the bike with the Metro500.
As an additional note, I had the Sigma, same model as yours, and always had interference problems with it. Maybe it's been fixed with a newer generation. It's resting in a baggie in the bottom of my parts bin.
As an additional note, I had the Sigma, same model as yours, and always had interference problems with it. Maybe it's been fixed with a newer generation. It's resting in a baggie in the bottom of my parts bin.
#9
Senior Member
Joined: Nov 2008
Posts: 633
Likes: 0
From: Central, CA
Run Garmin 510 or 1000 and use cygolites 720 and 850 on both sides of the out front Garmin mount. Used the lights for rides in the country with no street lights and about as black as night can be for up to 1.5 hours at a time an No issues with interference.
#10
Full Member

Joined: Jun 2007
Posts: 444
Likes: 32
From: Cleveland
Bikes: Bob Jackson, Trek & Sampson
The light probably has a Switch Mode Power Supply to convert the DC battery voltage to a different DC voltage or maybe AC voltage. It does that by rapidly switching the battery voltage on & off, then running this crude AC voltage through a transformer that changes the voltage. A SMPS may generate a lot of noise voltage. Take a battery power AM radio, tune it off-station near the low end of the dial and you can hear (maybe) this SMPS noise. Aluminum foil might work as a shield.
#11
Senior Member
Joined: May 2013
Posts: 4,400
Likes: 106
From: SF Bay Area
Bikes: Bianchi Infinito (Celeste, of course)
The light probably has a Switch Mode Power Supply to convert the DC battery voltage to a different DC voltage or maybe AC voltage. It does that by rapidly switching the battery voltage on & off, then running this crude AC voltage through a transformer that changes the voltage. A SMPS may generate a lot of noise voltage. Take a battery power AM radio, tune it off-station near the low end of the dial and you can hear (maybe) this SMPS noise. Aluminum foil might work as a shield.
LED lights only work off DC current, most lights control the output using high-frequency pulse-width-modulation (PWM). Similar idea to a switch mode power supply, but you don't actually use it to change voltage, you just turn the light on-off very rapidly so that you don't see any flicker. This is a very simple way to modulate the output of the LED, in a very efficient manner.
To the OP:
GPS based bike computers typically use either ANT+ or Bluetooth LE for communications. Those are digital signal protocols that are significantly more resistant to interference than any analog format. Either will completely solve your problem.
It's the main reason that I never recommend either cheap wired computers (<$20) or GPS units. Anything else is rendered useless by most lights.






