HAHA< don't know who told you running 29 inch tires shouldn;t cause loss of power, but who ever did tell you this lied thru there teeth to you
going to 29" tires, you altered the stock gearing, and that robbed a LOT , NOT a little, a LOT of power from your atv, IF you wish to get back to STOCK like power, only thing you can do is add a gear reduction to TRY and get back to stock gear ratio's that are now GONE from them larger tires
HONDA atv's make very small amounts of HP<> and there is NO easy or cheap way to get more HP in them as said above
you'd be better off selling this atv and BUYING a atv with more HP that can handle this sized tire, NOT what you want to hear, but its honest advice
honda 500 CC atv's have like 32 hp, other brands 500cc atv's have like 50+ hp?
larger cc motors would STILL be better for 29 inch tires, as even on the other brands 500'
s 29 inch tires is ASKING a lot of ANY 500 CC atv on stock gearing
get into a 800+ cc motor and well, you THEN have extra hp to loose for them BIG heavy tires! till then IMO< without altering gearing to MAKE things work with tall tires, your just wasting your MONEY and going to be disappointed in what you end up with on STOCK gearing