Weight is 1kg. Output is a relatively lowly 12v x 2.5ah though. I don't know how this compares to the oem NSR battery, but it might be something to bear in mind if the PGM, Powervalve servo etc. are fussy about battery output? It certainly wouldn't be worth cooking yer PGM for the convenience of a smaller battery...

You can pick them up easily and relatively cheaply enough nowadays though (around 25 quid - quite a few modern 'peds use the same battery ) so it might be worth picking one up to try?

I found that the ability to mount it where and in whatever orientation you like was very useful when I 'converetd' the 3MA. And because I did away with the 3MA's big under-engine battery and tool box combo unit the job saved almost 2kgs net. Thus making it very worthwhile for me. The NSR's battery box set-up is far less bulky though as I recall so your net weight saving is likely to be much less. I can definitely understand the convenience line of thinking though.

I'd offer to send you one to try, but the only good one I have is currently fitted to the daily commuter 3MA I'm afraid.