Speedo overreads

[Cigaro]

I've always suspected that the speedo on the 250 overreads, but after being followed by my mate the other day (in his car) I've confirmed it. His speedo was reading about 25mph, mine slightly over 30.

Now I know why so many drivers seem to have an obsession with tailgating me!

What could be the cause of this? Worn/sticky speedo cable? something else?

[Kickstart]

Hi

Assuming it is a cable speedo driven from the front wheel.

It is was the cable wearing then it would need to catch up to the right speed pretty rapidly to avoid snapping the cable.

That pretty much leaves a worn out speedo (basically is turns ones magnet inside another, so dragging the outer one round), or a front wheel / tyre that is rather smaller than it should be.

Or the speedo was just never that accurate.

All the best

Keith
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[the grim reaper]

If it is a cable from the front wheel then I would expect it to under-read rather than over read, if the cable was playing up. Assuming 1-2mph error in your mate's car speedo, yours is well over 10% over reading, which is outside the recommended spec.

Is it an import? Could be that someone has fitted a KMH to MPH converter or similar, you can buy mechanical ones of these. If not then I reckon the speedo is knackered/worn. The speedo will have a number of gears inside to convert the cable rotation to needle rotation, take the clocks apart and check these are not sticking, or that the needle mount has become twisted. Does the needle return to 0mph when you stop?

Cheers

Grim
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[LanaTheGreat]

I need a woman

[LanaTheGreat]

My friend's scooter speedo also showed a higher speed than what he was actually riding (120km/h when riding @ 90km/h). This was on a brand new Skygo scooter. He ended up adjusting the spring inside the speedo, tightening it slightly so that the speed was closer to normal, using a GPS to check if he was riding the correct speed.

He got the speedo quite accurate now.

[nightshaddow]