Speed meter

GoldenMotor.com

Scol

Member
Jan 10, 2014
44
0
6
Ireland
I have a wireless speed meter it reads normal when I’m cycling but when the engine is on it’s readings are wrong it keeps jumping to random numbers.

The engine is affecting the reading. Should I change this to a wired unit ? or is there a quick fix ? I was think of putting some insulation tape on the handle bars because then I take the unit off the handle bars it seem to work OK and get a good reading from the sensor on the wheel so It must be picking up some interference from the engine through the frame. I have a wired speed meter on another bike I could change it no problem but before I do are all speed meters affected by the engine ?

Scol.
 

Sidewinder Jerry

Well-Known Member
Dec 19, 2011
1,996
928
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Rockwood, TN
I personally prefer wired ones. They are cheaper and very reliable. The wireless operate of a radio frequency. The engine could be emitting a sound frequency that interfering with it.
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
I have a wireless speed meter it reads normal when I’m cycling but when the engine is on it’s readings are wrong it keeps jumping to random numbers.

The engine is affecting the reading. Should I change this to a wired unit ? or is there a quick fix ? I was think of putting some insulation tape on the handle bars because then I take the unit off the handle bars it seem to work OK and get a good reading from the sensor on the wheel so It must be picking up some interference from the engine through the frame. I have a wired speed meter on another bike I could change it no problem but before I do are all speed meters affected by the engine ?

Scol.
mount ignition coi/CDIl as far from front of bike as possible away from speedometer so there isn't RF interference, with a wireless speedometer I mount my coil on the seat down tube and just extend my wires and use a longer spark plug wire if needed, I use the cheapy wireless speedos I buy on ebay and been using them since 2009, units only cost $10 or less and work great when CDI is mounted behind engine on seat down tube.

Here is the speedo I use

http://www.ebay.com/itm/Waterproof-...819?pt=LH_DefaultDomain_0&hash=item460ff9c0f3

http://www.ebay.com/itm/Bike-Bicycl...467?pt=LH_DefaultDomain_0&hash=item1c3232bdc3

This other one I listed below is a wired model that I have and it works excellent also for about the same $'s

http://www.ebay.com/itm/New-LCD-Bac...prg=20140131104706&rk=2&rkt=4&sd=360929879200

Map
 

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2door

Moderator
Staff member
Sep 15, 2008
16,302
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Littleton, Colorado
Lots of reading here about 'speedometer problems'. http://www.google.com/cse?cx=partne...c.tab=0&gsc.q=speedometer problems&gsc.page=1

I never had much luck with the wireless type and I do about the same things as mapbike does. The odd thing is I had one bike that never had a problem with a wireless speedo but every other one had the same symptoms Scol, the OP is having. My wired speedometers all seem to work well.

Tom
 

mapbike

Well-Known Member
Mar 14, 2010
5,502
109
63
Central Area of Texas
I think it about experimenting to see what you can get to work the best on your bike, I started off trying to use a wired speedometer and it would go crazy as soon as the engine starter, but the wireless worked great, since then I have used both and have had good result with both, only thing that will mess up my speedometers now is when I run my high powered LED headlight, as soon as I plug the light in and turn it on it kills my speedometers until I turn it off, I guess the LED circuitry emits some type of RF that messes with the speedometers, I've tried newer and the old Stewart Waner analog speedometers on my bikes and none of them read correctly and none of them lasted very long, they just dont atke the beating my bikes deal out on them so I'm done waisting my $$$ on the old school mechanical speedometers.

The one I posted links to in my previous post all work great on my bikes, I set them up and then check them with GPS to confirm they are accurate, they're good bang for the buck and hold up to the vibes and getting knocked around for me.

but I'd try moving the CDI before I gave up on the one you are using now Scol, if that doesn't work i'd try a good wired one and see what you get out of it, one or the other will work out i'm sure.

map