Help please.

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Out on my Specialized Vado yesterday and the motor stopped assisting. Alarm up on computer saying motor problem, could be speed sensor. Found the sensor and magnet on rear disc and cleaned it with my finger. The magnet was covered with black dust. Started up again and all good to get me home. At home got a small brush and a duster and cleaned the magnet some more and the sensor. Sprayed some disc cleaner onto the rag and cleaned sensor and magnet again. Out for a ride this morning and assist missing again after 9 miles.
Rang Specialized and he said it will be either Magnet, Sensor or Cable.
Any ideas. Got it booked into my LBS Thursday. Thanks.
 

CXRAndy

Guru
Location
Lincs
Do you lose the speed in the display? I'd check alignment of magnet in relation to sensor. Some sensors have a line or arrow to indicate where the magnetic should pass over. Also sometimes the magnet needs to be slightly nearer or further away in gap to give reliable signal. The magnetic field can be more effective being further away.

Check if there is a connection before the wire goes into the motor, it might not be properly connected.

Else check with maker
 
It's almost 6 months since you bought your bike, so you have 18 months left of your warranty covering mechanical parts; even better you bought it from your LBS. I remember you saying how good the shop was, so they will definitely see you right on Thursday. You might not have been so fortunate if you'd bought it at a chain. All will be well and you'll be smiling again soon.
 

88robb

Regular
Location
Netherland
Out on my Specialized Vado yesterday and the motor stopped assisting. Alarm up on computer saying motor problem, could be speed sensor. Found the sensor and magnet on rear disc and cleaned it with my finger. The magnet was covered with black dust. Started up again and all good to get me home. At home got a small brush and a duster and cleaned the magnet some more and the sensor. Sprayed some disc cleaner onto the rag and cleaned sensor and magnet again. Out for a ride this morning and assist missing again after 9 miles.
Rang Specialized and he said it will be either Magnet, Sensor or Cable.
Any ideas. Got it booked into my LBS Thursday. Thanks.

The magnet itself is likely cracked or damaged. Even a hairline crack you can't see will stop it working properly. The dirt was a temporary fix. Replacing the cheap magnet on the disc rotor is the most common fix. Your bike shop will test it, but that's the usual culprit.
 
OP
OP
Saracenlad

Saracenlad

Über Member
Do you lose the speed in the display? I'd check alignment of magnet in relation to sensor. Some sensors have a line or arrow to indicate where the magnetic should pass over. Also sometimes the magnet needs to be slightly nearer or further away in gap to give reliable signal. The magnetic field can be more effective being further away.

Check if there is a connection before the wire goes into the motor, it might not be properly connected.

Else check with maker

Thanks Andy. Yes, the speed disappears as the motor cuts out. LBS tomorrow fingers crossed.
 

CXRAndy

Guru
Location
Lincs
No the sensor should be firmly in place.

You mentioned a cracked magnetic. That would spoil the magnetic field, possibly making the sensor not see it. Magnetic wheel speed sensors are only a few pounds from Amazon etc.

Seen as you are taking it to the service centre let them fix it.

Ask what it was when fixed
 
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OP
Saracenlad

Saracenlad

Über Member
Spent all morning today at our LBS. Hells Bells!!!
They secured Sensor. Test ride and still no assist.
Took cover off BB and did something with wiring. Test ride and still no assist.
They plugged a computer into my bike and it said all was good.
Test ride and still no good.
Gave up and left the bike at the shop. At home I rang Specialized. They said they would talk to the shop and get whatever parts are required to them ASAP. They said Speed Sensor main culprit.
Not heard owt since.
I did ask the Specialized guy how a £2650 bike could fail so badly in 5 months? Didn't get a response.
Spent the afternoon fettling my Saracen.
 
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Saracenlad

Saracenlad

Über Member
Phone call from Specialized today. New motor and sensor pack sent to LBS. Had a call from them too to say all parts arrived at shop and will be fitted today or tomorrow.
I think I need to know what the problem was. Find out at shop hopefully.
 
Very good and quick response from Specialised and helpful LBS. I told you that you would soon be smiling again but you're right that a quality item should not fail at 5 months. Occasionally even good things go wrong, but quality manufacturers usually do the right thing. Onwards
 
Just seen this
but was going to say that I have had that sort of problem several times
and it was always wither a broken sensor (once fixed with some tape
of teh magnet had moved on the spoke and need readjusting and the screw fixing tightened up a bit - and moving back into position

Great support from Specialised and the LBS - good to hear
not really sure why anything to do with the motor was needed though??


did happen to mine once - the sensor cracked and even gaffa tape would not hold it in place!
a new one from Bosch was fitted by the LBS and all was well
 
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