Recently since a top end my starter doesn't want to immediatly turn over. It acts like my old Harleys did but only when warm. Hit the starter and there is a delay before it starts to crank. I usually have to bump it a couple of times to get it to turn over.

The top end is new, valves, pistons, guides etc, I never had this issue before the rebuild. I have replaced ground and cable to the starter and cleaned connections.
The battery is new. When the engine is cold it will turn over easily and continue to turn over for several seconds with (with gas off so it won't fire).

So far it has never failed to start without a little coaxing.

I am considering the ND starter conversion from Motoraad Electric $350, The EU electric starter for $175 (probably Chinese), and having the Bosch rebuilt.

Any advice welcomed.