Tried to start my car for the first tim in a while yesterday and the starter was really struggling to turn over the engine quick enough for it to fire.

So I charged my battery overnight (reads 12.6v with ignition on, 12.85v with it off - so assume good)
Cleaned all my earths and terminals.

Still struggling to turn over.

I then removed the spark plugs and it turned the engine over quite easily (ie nothing seized etc).

Engine is bored out and starter sometimes struggles when the engine is hot, but never had any bother when it is cold.

Even took the starter to bits, but everything looks in good nick inside.

Tried connecting an extra, fully charged jumper battery, still no really improvement.

Is it knackered and is there anything else I should try before forking out on an expensive new or uprated starter??

hi this is a common fault with tuned busa motors contact carl at extreme engines he supplys an up graded starter motor loads of cranking power