speed sensor/ sprocket nut help

hello guys

ok after fixing my ecu problem...........i know have another one ;D :D

my bike isnt reading any speed or clocking its miles

talking to jd we have narrowed it down to the speed sensor itself.

checked all wiring/plugs all good.

i removed the front sprocket cover along with the speed sensor.

the sensor seems to have a deep scratch on it u can see a copper colour metal in the scratch.....

would this afffect the sensors operation?

also whilst there i checked the general sprocket area and came across something a little worrying

the main front sprocket nut moves. i can rotate the nut 1/4 each way.....there is a retaining nut also on the shaft , now i am assuming that main nut should not move what so ever.

does anyone know how the speed sensor picks up its signal ?

as for the sprocket nut.....i think its a 36mm can i just tighten it up and refit retaining nut?

cheers

Dan

Can you post pics????

Is hard to tell from the description.

i can if i can find my micro sd card adaptor

The speed sensor is an inductive or hall effect proximity switch. It should never touch, but comes in close proximity to a metal object ie the corners of the nut and creates a tiny pulse for your electronic speedo. Because your nut was loose it has rattled about on the shaft and destroyed the coil winding (the copper bit you can see). They are non serviceable therefore most probably B*ggered.

Quote:

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Originally Posted by Cemorah

The speed sensor is an inductive or hall effect proximity switch. It should never touch, but comes in close proximity to a metal object ie the corners of the nut and creates a tiny pulse for your electronic speedo. Because your nut was loose it has rattled about on the shaft and destroyed the coil winding (the copper bit you can see). They are non serviceable therefore most probably B*ggered.

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as i suspected cheers m8

2nd hand speed sensor fitted (£12 BARGIN!!!) works perfectley :)

Did you tighten the nut up as well? :)

yeah mate removed it cleaned everything up down there and re-fitted nice and tight

Surprised there wasnt a locking tab washer on it.Did you put any Loctite thread lock on the shaft before you tightened up the nut?

Quote:

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Originally Posted by alanTDM

Surprised there wasnt a locking tab washer on it.Did you put any Loctite thread lock on the shaft before you tightened up the nut?

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yeah put locktite on it....i did think there shud be a locking washer on it or something