bipedfred

I'm still dialing in my new commuter rig and this morning I was checking the calibration of my dB4LW wireless cyclometer, cyclocomputer, speed-o-meter, whatever... against my GPS. I took off a little earlier than normal and my computer was showing me making 35mph, which I didn't believe even for a tiny little bit.

Turns out it was picking up extra clicks from my Planet Bike Beamer 1 led headlight, which I needed because it was still a little dark, which was set on blink mode. The light is mounted below and off to the side from the computer (about 6 inches away).

I can understand why this is happening, it's just that I was expecting a little better signal discrimination from the computer.

So is the dB4LW just a flawed design (it was very, very inexpensive) or should I expect the same from most other reasonably priced wireless units?

(PS: I expect my VDO-C3-DS would do better at filtering out the noise, but I'd rather mount a wired unit than use that again)

Paul L.

Mine picks up the GPS if it is mounted to close as well.

Pig_Chaser

You're right, the computer shouldn't be fooled by the blinking light. I wonder if it was actually the wheel sensor picking up the blinking headlight; the sensor for the magnet can be sensitive to electromagnetic fields.... try moving the headlight further away from that magnet sensor. Kind've a long shot because they have a pretty weak pick up in the sensors (that's why the magnet has to be so freaking close).

Could you use a solid 'on' state for the headlight? I'm guessing that should end the interference too whether it's the computer or the sensor picking it up.

Just a couple ideas anyways.

ok_commuter

I want the same setup you have. Imagine looking down to see 35, 40 mph in the flats! I might just have to modify the blinky to see if I could go any faster!

MNBikeguy

Unfortunately, it's not exclusive to your unit; any wireless comp will perform erratically in close proximity to other electronics.
As soon as manufacturers realize wireless bike comps share valuable handlebar space with a lot of other items, we're stuck in the mud on this issue.
With my GPS on, I can be cruising at 70 mph. Not bad, eh?

JTGraphics

The dB4LW in my experience is really bad with interference. My VDO-C3-DS units I have not had any trouble with it, I know some complain about them but all my units 3 in total all work great.

veganboyjosh

just add another magnet, and double your speed and mileage.

vaticdart

I used a Wireless Cateye Strada that got all sorts of interference from a NiteRider Sol, a CygoLite Dualcross, a Dinotte 200L and a few different blinkies (the Knog Frog didn't cause any interference!). It was great during the day, but at night my top speak was always 65 mph. As much as I liked the wireless thing, after my display partially died I just bought a cheap Topeak wired thing which has been interference free.

bipedfred

I did a quick test on the way home today - with my head light on steady it yielded a steady 0mph.

I bet if I switched the light and computer, where the light wasn't in-line with the computer and the sensor and got it a little further away then it would work with only an occasional glitch... or I could order a Planet Bike wired 8.0 for $19 from Amazon, have it by Thursday, and toss the dB4LW.

Yeah, I'm doing the last thing.

ottawa_adam

I get the same thing with my filzer. I mounted my headlight far away from the unit and things work fine. I occasionaly get drifts from other electronics nearby but not enough to make a big difference.

squirtdad

I had interfence from my blinkin led light. I eliminated this by move the light so that it was not in the light of sight between the magnet and the speedo. I.e my magnet is on the left side of the front wheel. when I put the light on the left side of the speedo, I got interference. I moved the light to the right side of the light as as I could and no interference.

jimbrown

!!

jimbrown

I have to agree with this statement. I had a dB4LW and the thing would have interference constantly. So It lasted one day then I packed the thing up and traded it in on the more expensive VDO-C3-DS and that thing has never I repeat never had interference. It may have something to do with the fact that the signal is digitally encoded, like a home cordless phone. The only complaint I have is the battery's lasted about 5 months on the first set. That was two months ago. So I have not replaced them a second time so I don't know if it was just them or not. Plus I did not know if it was just one battery or not, the system I have has 3 since I have the cadence sensor also. So I replaced all three to be safe. It really is a great wireless computer.

Caspar_s

It's the dB4LW. I can take a 100km trip to the mall - although it depends on how long I am inside, because in certain areas it will run constantly. Also as I ride past certain electronic doors. I just check to make sure the thing isn't past my normal distance on my commute and don't use it until I have caught back how much was artificially added. Other rides I don't normally go into stores so it isn't a problem.

The other thing is I haven't bothered with it for a month - it's on the other bike which needs wheel attention.