That depends on what you want to do with the atv. Do you want a sport atv for high speed and excellent handling that can take the jumps like a motocross bike but does not pull things well and is not a 4-wheel drive atv or do you want a utility atv that doesn't handle as well at break neck speeds but has tons of torque for exploring the mountains and working on the ranch pulling things???
I've owned hondas and they are very reliable. I still have a honda 250trx that was built in 1984. It's used every day of the year. So far the only item that has been replaced was the battery. The new hondas are reliable and have a plush ride but not as powerful as say a yamaha, polaris or kawasaki.
I also own a kawasaki 2002 prairie 650 and a 2003 prairie 360. These bikes are 4-wheel drive speed demons. The 650 will do well over 65 mph and has the capability of locking all four tires into the drive system. These have been very reliable for the first 500 miles i've had them but they do not start up as fast as the yamahas and hondas.
In my area used bikes bring almost as much money as a new one. Alot of the atv companys are offering 0 down, 0 payment 0 interst for 6 months and 5.6% interest for the remainder of the loan. I'd go new if you can afford it, you never know how the used bike was treated. FYI I payed $5300 for the p360 and $6700 for the p650. It's alot of money but if I can get 10 years out of these it's money well spent.
Test ride every atv you can get your hands on, you'll be amazed at how each one handles.
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