I can understand the attraction of riding an ATV, as carrying a full pack and combat gear is exhausting, but I would have thought the noise of the vehicle would make them tactically useless:
ATVs (all terrain vehicles) have proved particularly useful, and popular in Afghanistan. There are many models in use, all of them militarized civilian vehicles. The British use a militarized versions of the Yamaha Grizzly 450. Basically, the Grizzly is a four wheel, 628 pound, cross country motorcycle. This ATV is six feet long and 3.5 feet wide. In addition to the driver, there are racks on the bike that can carry another 175 pounds. In addition, the vehicle can tow a trailer carrying another 350 pounds of cargo. Top speed, on a flat surface, without a trailer, is about 75 kilometers an hour. Cross country, it’s usually about half that, and a bit less if a trailer is being hauled.
Four years ago, the British Army bought 250 of the Grizzly 450s, and these were very popular with the troops in Afghanistan. There they are used for patrolling, and hauling supplies to troops in isolated positions. The army is paying $41,000 for each bike, although that includes a trailer, spare parts and technical services. The civilian version goes for about $8,000 each.