Suzuki 2 Strokes

I have just repaired my starter clutch. The three screws holding it together had sheared off and the whole thing was rattling about. I have replaced the rollers and springs, cleaned it all and reassembled it. When I first tried pressing the button the engine turned over beautifully, but only once. Ever since when the starter button is pressed all that I get is the solenoid clicking in and out. There is no movement of the starter motor at all.

I took the motor out and although it rotated, it was slow and I could actually stop it rotating by hand when it was connected to a car battery. I took it apart and cleaned all the contacts and brushes and it was better but still will not turn the engine. I suspect it is faulty.

Are these motors prone to this type of issue? I am sure that the rebuilt starter clutch is fine. The bike kick starts with no problem. It is just odd that it worked once and then completely stopped. It is worth pointing out that the bike has been stood for ten years and the starter clutch had obviously failed sometime before that so it could be age?

A little bit of info would be nice, like where are you based etc.
The 550 starter motors are reliable, but everything fails eventually.
Refurbed motors are available in the UK.
Check the battery to motor connections and also battery to earth cable (to the engine).