Some dealers will put a factory 300 cylinder and piston on your bike for you which would not void your warranty.

Now if you did a big bore and had a warranty issue, you could always put the stock 250 back on and be like wtf

But I would recommend putting a 1,000 miles on your bike before doing a bore...just to be safe and work out any kinks ya might have....most don't end up having any.

 

agree; 'cept that the dealers more than not just want to sell you the bike. anything they mod or install on the bike will NOT be warrantied by kawi and it may be like pulling teeth to get warranty coverage. any warranty on add on parts would be thru the dealer and they won't pay up, guaranteed.
but yeah, just swap the jugs back and be like wtf. that's good and I like it finger. but, that's a lot of work but it'd be worth it.