well mine stopped running properly when i laid it up because of the snow and yet it ran perfectly before the snow arrived... the starters are fairly small and easy enough to change however if you are not confident doing it yourself get a mechanic to do it for you... you can check to see if the starter is knacered by taking out the spark plug, then plug the spark plug back into the plug cap and rest it on the engine or somewhere else metallic... then press the starter and see if the plug is sparking.. if it is then the engine is turning over and if not then its not... also you will here the piston going up and down with the plug out