The zillas should do well for you, untill you are in super deep mud. When you are riding deep deep mud i would get your self a set of 28 inch silverbacks. You can go up to a 30inch wheel on these bikes and have no clearence issues. Yes if you put a bigger tire on it, it will void your warrenty if you show up to the dealer with them on. Best bet is to keep your stockers, and just put them on if you need dealer to do work for you.
I would think that the 550h1 would have more then enough power to turn your zillas. How ever for the type of riding your doing would look at Outlaw MST's.
Now if you are in super deep mud with a heavy mud tire like a silverback, for mods i would just do the airdamn clutch mods.
What do you is search for airdamn on here, find the link to his website.
What the mod does is this, you pull your primary sheave out and you mail it to him. He machines it, cuts up to like 3mm out of the primary. This allows the belt to sit much lower on the primary doubleing your low end. No need to get a clutch kit, no need to reclock your secondary.
Also the nice thing about this mod, unless the dealer measures your primary which i doubt they will ever need to.
Air damn has 1000% positive feed back for this work. Also his machine work is as cheap if not cheaper then buying a clutch kit and rollers. He charges 100 dollars including the shipping back to you. He can usually send it back to the day after he receives it.
Used for work "farming" "cutting wood" and play
2006 400 4x4 M
Warn 2500 pound winch
Home made baskets
25' Kenda Bear Claws
880 HID Low Beams Only
Front & Rear bumpers
Moose manual lift snow plow, converted to work with winch.
Electric seeder / salt spreader
Rear Hooks for log chains
Custom built railroad tie drag
Home made fence stretching attachments
To Do List
Reverse Cam, Camber Mod
2006 400 4x4 Auto VP - Stock
08 700h1 -Stock