So might be trading my trx450 for a 2001 cr500 that is in great shape. i also have a 2007 crf250r 4 stroke that the previous owner took no care of maintence on the engine so basicaly it needs a complete head/valve job. if i get the cr500 i was thinking of pulling the 250f motor out of the crf and putting in the 500 2stroke in. i have always been a huge fan of the cr500af and would love to do this project. Could someone give me a breakdown of what i will need to do the swap? i know the Y has to been cut and moved up on the crf frame but is there a measurement to go by? Is there a kit i can buy that will include the front motor mounts, coil mount and rear swing arm spacers and anything else that might be needed for the swap.? any tips would be great. i am thinking about parting out all the crf250r parts that wont be needed. like the engine, it acually a 2008 250 engine that was that replaced the 2007 and the kid just never shimmed the valves so it beat itself up. It has a full Yosimura dual exhaust and would also like to sell the carb. could someone tell me what a fair price i should ask for these parts? is there anything else i can pull off the bike and sell that wont be needed for the cr500 engine?