Very slow engine turnover

[eightballdh]

My 82 supersport struggles to turnover, I have replaced the battery, battery cables, checked and double checked all connections. I hooked the battery straight to the starter all with the same results. The engine will turn over fast if the spark plugs are removed. I have checked the compression which is normal on all cylinders and feels like it should if I remove the timing cover and turn it by hand. I removed the starter and dissasembled it, everything appeared to be in good working order. Any advise would be greatly appreciated.

 

[MickMick]

Have you checked for corrosion or poor connection on the the starter motor stud? If that is on, then motor or contacts. I would first remove the cable from the stud and clean it up. If no joy, replace the motor bushes and clean the crud between each contact on the armature. I don't think a used replacement starter motor. Ps, check your battery negative to earth and engine.

 

[eightballdh]

The stud did have some corrosion on it, I took everything apart and cleaned it and now the engine turns over just fine. Thanks again

 

[MickMick]

Excellent.