American Ben Spies said this morning that he won’t be riding for Yamaha in MotoGP next season, that he has made the decision to leave the factory Yamaha team at the end of the 2012 season.

Spies said via email this morning:

Yesterday I made a comment on Twitter to cause a stir. (Today) I’ll be more in saying that I have chosen to leave Yamaha after this season for a litany of reasons. I will explain more when I feel it is appropriate. I’m discussing my situation with my sponsors and they are behind me. There are a few people at Yamaha who I hate to leave. And they know who they are. I wish Yamaha the best. I won’t make any further comments until the offical announcement comes out.

Spies won the World Superbike championship for Yamaha in 2009–his rookie season in WSBK. That remains Yamaha’s only WSBK title.

Spies also scored rookie of the year honors in Grand Prix in 2010 and also won the Dutch TT last season.

He also nearly won the final Grand Prix of the 2011 season at Valencia, but was beaten to the line by World Champion Casey Stoner.

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