+100.
The speedometer has to be inside the fork, with the driving tab engaged in the spokes so the wheel will turn it. It cannot be outside the fork since than the driving tab will be stopped in half a turn when it hits the fork blade.
BTW- The first question would have been is whether it worked before, If so, we know the unit was OK. But now you need to take it off and confirm that the driving tab didn't break off because you mounted it wrong.
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