Max IV Newbie

I purchased my first 6x6 a few months ago. Its a 2007 Max IV with the 18hp briggs motors. It was owned by a older gentlemen who only put 79hrs on it. I've rebuilt the fuel system and added a couple extras I picked up from the forum. It took me 6 months to find it. Now that I have it and got it to run better I need a lot more power! I don't think its strong enough to pull my wife, daughter and myself around without struggling. I have already put it on craigslist once but wife wants to see if we can upgrade it and keep it. My daughter loves it. Researching on here Ihave found lots of information on the bandolero motors. Does this swap require a lot of modifications to install or is it a drop in turn key? If its too much to mess with I'm selling the Max IV and starting a new project. Thanks for all the information

Sounds like there are minor issues that may need attention, it should haul you around fine, large hills may require more engine if loaded heavy. If you are able to post a video of it, driving from inside vehicle and what clutches do in neutral, may get allot of responses from what people hear and see.
Little tweaks cure big problems.

Often times frustration occurs from not knowing what to expect the machine to do or not do.

The clutches either both spin when in neutral or just the top. Tts about 50/50

sounds like loose/worn belt.

Thanks for the help. I'll check that out

To tighten your belt, you add washers under your engine stand. It's somewhat of a PIA, but that's how it's adjusted.

There are many threads on this forum and on the engine and transmission forums to guide you along with checks. Engine rpms are also very important in the performance of your machine. A good unloaded (neutral) rpm for a briggs 18 is between 3600 and 4000 rpms, lower than 3600 will greatly affect performance as will a loose worn belt.

Often times a properly performing machine will "turn that frown upside down".

Check to see if the recommended belt is installed. Replace when it's worn out.
Another option is to install a red spring in the secondary/driven clutch. This spring makes for more low-end power.