I've found NSR's (all the ones I've had on track) occasionally jumpout of gear if you clutchless upshift, especially if you're not really positive on the shift.

The jumping out of then quickly back into gear thing sounds a little like something the CBR400 and RVF400 are both prone to (but not in a high gear, normally in 2nd), those in the know attribute it to worn dog teeth, it's a common fault, especially with CBR's. It feels almost like the chain jumps a tooth. Never heard of it on the NSRs though.
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