At 34lbs she's a robust but weighty beast.  I've already earmarked my spare Pike Airs for it, not to mention swapping the heavy ISIS cranks for new Stylos but it's still a tad tubby for my liking. 

Realistically, where should I start to look next?  Can I make big gains by swapping out the bars and stem, or should I look to fitting a lighter wheelset? 

Should I be looking at a tubeless setup?

Git!

Yes, I'm losing lbs there too...

It was a flippant remark but it's a fair point I think.  I've never seen the point making the bike as light as possible if you're of a....erm....rotund persuasion.  It must be more cost effect to lose a couple of pounds.

Is a lighter bike more 'chuckable'?  Actually, a different question....

Is a 200lb person on a 25lb bike more chuckable than a 195lb person on a 30lb bike?

Ahem, I'm a healthy 12 stone five and just a gnat's under six foot, so no issues there! 

It's a good point though, I've been held up by a fat bloke who was jolly proud of his sub 23lb full susser which cost an arm and a leg.

It's the long, draggy climbs that are killing me on it, which is why I'm asking about going tubeless - don't tubeless wheels roll better?

Cheers guys. 

 Any pointers as to rims and rubber? 

2.3" Kenda Nevegels.   They're grippy but not surprisingly very draggy.

Damn, hit F5 and reposted.  Sorry!

Probably the best way would be to run a set of UST rims and some slightly less draggy tyres, something like Spesh Eskars or Bontrager Jones.  Trying to find a Mavic rim that bridges the gap between hard XC and light freeride isn't very clearcut though, I would be grateful if someone could kindly make any suggestions?

Realistically, can I expect to lose a significant amount of weight by switching the stem and bars from OEM items?