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NFJ79
03-04-2011, 02:04 PM
My speedo on my Lifan 200gy-2 is completely off. Is this common for these bikes. My top speed for my gearing is about 53mph. I tested this out by mounting my garmin gps to my bike. Doing 53mph, my speedo says 80mph.
I also installed a Bell wireless bicycle computer hoping that would help but I think its picking up electrical interference and is not accurate. Thinking about trying out a wired bicycle computer and seeing if that helps.

How can i fix my speedo?

Barnone
03-04-2011, 02:13 PM
NFJ79,
Never heard of a speedometer that far off. Maybe it's not the origional speedometer or drive mechanism.

FastDoc
03-04-2011, 02:20 PM
To be honest I'd just memorize what the speedo indicates at certain key speeds like 30, 45, 55 and call it victory.

NFJ79
03-04-2011, 02:22 PM
NFJ79,
Never heard of a speedometer that far off. Maybe it's not the origional speedometer or drive mechanism.

I bought the bike from my friend who is the original owner. The bike had 185km on the dial when i bought it from him.

I'm going to try mounting a bigger magnet for the bicycle computer.

Barnone
03-04-2011, 03:34 PM
Are you reading KMPH thinking you are reading MPH? Or have a MPH face on a KMPH speedometer.

Weldangrind
03-05-2011, 01:05 AM
That makes perfect sense, because 50mph is about 80km/h.

For further reference, 30km/h is about 18mph, 40km/h is about 25mph, 50km/h is about 30mph, 60km/h is about 36mph, 70km/h is about 42mph, 90km/h is about 55mph and 100km/h is about 60mph.

The simple rule that I learned when Canada switched to the Metric system is to drop the zero from a metric speed and multiply by seven. Drop the zero from 50km/h to get 5, multiply by 7 to get 35mph.

I only had old cars with Imperial speedometers, so I got good at doing the math. :lol:

SpudRider
03-05-2011, 06:13 AM
Wireless bicycle speedometers don't work well with motorcycles. ;) I suggest you try a bicycle speedometer with a wired connection. :)

Spud :)

NFJ79
03-08-2011, 04:42 PM
That makes perfect sense, because 50mph is about 80km/h.

For further reference, 30km/h is about 18mph, 40km/h is about 25mph, 50km/h is about 30mph, 60km/h is about 36mph, 70km/h is about 42mph, 90km/h is about 55mph and 100km/h is about 60mph.

The simple rule that I learned when Canada switched to the Metric system is to drop the zero from a metric speed and multiply by seven. Drop the zero from 50km/h to get 5, multiply by 7 to get 35mph.

I only had old cars with Imperial speedometers, so I got good at doing the math. :lol:

No my speedo is in MPH. Says MPH at the bottom.

Tested my speedo again. 53mph reads about 60mph on my tach. So its about 10% off.

I like your simple rule converting kmph to mph. I'll have to remember that.

NFJ79
03-08-2011, 04:44 PM
Wireless bicycle speedometers don't work well with motorcycles. ;) I suggest you try a bicycle speedometer with a wired connection. :)

Spud :)

Yeah my wireless is picking up too much electrical interference. I'm gonna try a wired bicycle computer.

SpudRider
03-08-2011, 05:01 PM
Wireless bicycle speedometers don't work well with motorcycles. ;) I suggest you try a bicycle speedometer with a wired connection. :)

Spud :)

Yeah my wireless is picking up too much electrical interference. I'm gonna try a wired bicycle computer.
Indeed, every report I have read where a motorcyclist tried the wireless bicycle speedometers, the wireless units picked up too much electrical interference. ;)

Spud :)

Weldangrind
03-08-2011, 05:46 PM
That makes perfect sense, because 50mph is about 80km/h.

For further reference, 30km/h is about 18mph, 40km/h is about 25mph, 50km/h is about 30mph, 60km/h is about 36mph, 70km/h is about 42mph, 90km/h is about 55mph and 100km/h is about 60mph.

The simple rule that I learned when Canada switched to the Metric system is to drop the zero from a metric speed and multiply by seven. Drop the zero from 50km/h to get 5, multiply by 7 to get 35mph.

I only had old cars with Imperial speedometers, so I got good at doing the math. :lol:

No my speedo is in MPH. Says MPH at the bottom.

Tested my speedo again. 53mph reads about 60mph on my tach. So its about 10% off.

I like your simple rule converting kmph to mph. I'll have to remember that.

What do you mean when you say that it reads 60mph on your tach? Does your tach have a speed reference?

NFJ79
03-08-2011, 06:46 PM
D'oh sorry meant to say speedo.

Barnone
03-08-2011, 08:22 PM
Your first post said "Doing 53mph, my speedo says 80mph. " which is way off.
Now you are saying 10%.

10% optimistic is not that abnormal for motorcycle speedometers.

Weldangrind
03-08-2011, 11:30 PM
10% optimistic is not that abnormal for motorcycle speedometers.

Indeed. That can be the difference between an 18" and a 21" front wheel. Perhaps the speedo was designed for a different application, and theyjust stuck it on this model. Wouldn't surprise me.