the starter motor may be siezed this is a common problem due to water getting into the causing and you will need to replace the kickstart gears as these will be worn out, try www.dimons.co.uk they can supply you with both these parts,the starter motor is about £50.00 and the kickstart gears are £43.00 for a set, to double check that the starter motor is faulty you should power it straight from the battery and make sure you have a fully charged battery also make sure your starter relay is working test for power using a volt meter or a 12v bulb.
Phil,Gosport, January 2006