Originally Posted by
Mike
Which tires are you planning on running and what year is your Max IV? The newer style Max IV tubs can accept larger tires more easily. Either way, you may end up having to reshape your tub to make tires that large fit. If they will fit, then regearing your Max IV will help turn the larger tires more easily but first see what gearing you currently have.
Some Max IVs came from the factory with an 18HP motor and 26" tires. While they were a little underpowered, they still worked ok for basic trail riding. You probably would be fine if you are putting around but if you get into nasty mud or haul a lot of weight, that's when performance would suffer. You can swap the clutch spring to help out some and you could hop up the motor that you currently have a little.
If you do regear, then you will lose top end speed where, if you upgrade your motor, you can have the best of both worlds. It comes down to what kind of riding you like to do.