Entered a roundabout after being hard on the brakes with clutch in for the last part as I dropped down a few gears and ready to engage again ... leaned the bike whilst engaging clutch and no drive, nearly fell off! The engine had stopped ... started it again with the starter and I was away bloody sharpish as there was a lorry aimed right at me ffs! Similar thing happened when changing gear a bit slowly going down hill through a slight bend at quite slow speed with not a lot of braking on that occasion, the rear locked and swung round a bit, pulled the clutch, hit the starter and away again. Dangerous ...!!