The only ones you have to machine when using "6205" bearings are the INSIDE rear...I beleive the SPOKE model from YAM are using "6005" that DO NOT need any mod cuz the bearing is same as OEM..."6205" are WIDER better and much cheaper to replace and everyone carries them in stock, "6005" are harder to find, to confirm the bearing type look on the seal.
If you want my opinion I wouldn't oversize the rear inners, their already over stressed and take alot of abuse and by overseizing them you WILL stress your rails, the stock bolts will be fine with RED loctite.