Interference with trip computer

rh1968

Pedelecer
Oct 9, 2010
39
0
Hi all,

Finally got my conversion kit from BMS Battery, absolutely loving it I must say (thanks to everyone on this forum who's offered advice over the last few months!). My only gripe is that the motor interferes with my Cateye wireless speedo/trip meter: as soon as the motor is turned on the computer stops registering any input - it starts again as soon as the throttle's off. Anyone experienced this sort of problem, and better still know a way round it?

Cheers,

Rendel
 

flecc

Member
Oct 25, 2006
52,803
30,376
Don't know a way round it, but together with crazy readouts it's a common problem with wireless models and front hub motors.

No problem with wired computers though.

Only thing I can suggest with the wireless one is a metal plate under the handlebar computer connecting to earth as a screen, that might work to block the interference. That might have to be electrical earth rather than bike earth though.
.
 

Streethawk

Esteemed Pedelecer
Jan 12, 2011
634
15
Try putting the magnet and sensor on your rear wheel (sensor on the seat-stay is preferable to the chain-stay. Not always a solution though as some are not strong enough to transmit the longer distance between there and the handlebars.

Otherwise, a GPS based speedo may be the best bet.
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
I have only ever managed to get "wired" ones working on the front wheel when a motor is in it.

Good idea from Streethawk to put it on the rear though :p

Regards

Jerry
 

Streethawk

Esteemed Pedelecer
Jan 12, 2011
634
15
Keep it as far from your motor controls as possible on the bars too. Relatively small currents can interfere with computers, for example my 7.2v 900 lumen Lupine lights interfere with mine if they're within 6" of the computer head unit.
 

rh1968

Pedelecer
Oct 9, 2010
39
0
Many thanks for the advice, I've tried rear mounting, if you'll pardon the expression, but the signal's too weak. I'll try repositioning the computer - it's right next to the throttle at the moment so that could be the problem.
 

LeonardYoung

Pedelecer
Jan 17, 2011
52
0
Anything with a magnet in it, or strong current, will interfere with wireless cycle computers. I recently used my iphone to check the calibration of my mine and the numbers all go haywire when the two are side by side.

Same with my laptop. If I put my cycle computer anywhere near it, it goes crazy.

Leonard
 

Streethawk

Esteemed Pedelecer
Jan 12, 2011
634
15
The best cycle computers use the Ant+ digital signal standard, which is more reliable. I'd highly recommend one of those if your budget can stretch to it. They are still not immune to interference though, the only way to guarantee you wont have problems is to use a GPS based device, smartphone, Garmin Edge etc, which are even more costly.

The only cheap solution is a wired speedo. Wired or wireless, the current range of Bontragers seem the best, much more user friendly than Cateye, which while reliable, are typically Japanese when it comes to user interface (for some reason they insist that one button is best, when they could easily add more and that would make everything simple).
 

Phil_P

Pedelecer
Jan 5, 2010
34
0
Hi,
In my opinion all e-bikes should come with a simple computer and some basic lights. There is a ready made power source for the lights and a simple computer would only be a few pounds if fitted at the manufacturing stage.

What do others think ?

Regards
Phil
 

RoadieRoger

Esteemed Pedelecer
Nov 8, 2010
720
196
GPS Device

The only computer I use on my Ebike to log distances covered is the Maplins Holux GPS, which is still in the shop for £49 . It gives you loads of information such as Speed , Max. speed reached , time taken , altitude and less useful stuff such as CO2 and the number of trees saved through doing your trip on a bicycle ! I`ve also used it to calibrate the Speedos on my Motorcycle and Scooters .That`s how I found out the speedo on my Aprilia Leonardo 250 Scooter over-reads by at least 10 mph , even at 30 . That why Italian machines are so fast !
 

flecc

Member
Oct 25, 2006
52,803
30,376
That`s how I found out the speedo on my Aprilia Leonardo 250 Scooter over-reads by at least 10 mph , even at 30 . That why Italian machines are so fast !
:D. A Fiat Tipo I once owned had it's speedo starting point at 10 mph when standing still. There was actually a stop pin in the face preventing the needle dropping below that!
.
 

rh1968

Pedelecer
Oct 9, 2010
39
0
Thanks for all the advice gents - I've switched it over to the other side of the bars away from the throttle and it's registering fine now!