Other than the battery and the exhaust there are no significant savings to be had, it will always be a heavy bike for off roading.
Going to a single caliper and narrower rims will make it handle better and feel quite a bit lighter while riding, but won't much difference if the bike is lying on top of you.... Same with a catless header, around 1 kg less IIRC.
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12 690 Enduro-R, 12 Husaberg FE570, 09 KTM XC-F/ 450 RFS hybrid, 07 KTM 450 SMR, 09 BMW F650GS twin/F800GS hybrid, 03+05 YZF-R6