My 98 TE610 has 2,400 miles on it and almost all have been in the dirt. I changed the rear sprocket from a 48 to a 52 for lower gearing in the dirt. I also changed handlebars as the originals bend easily. Put a Big Gun exhaust system on with jetting changes recommended by them. Opened up the airbox by installing numerous circular vents with mini filters and changing the stock air filter to an aftermarket performance version. Put some hand protection on and removed the turn signals. Replaced the DOT tires with off road knobbies. Put a cold start valve on for easier starting. It runs great but you must know the starting drill when out in the boonies. No electric start on this model. A little heavy for serious speed on rough terrain but at 8/10s it is great. The modified motor is great. Problems to date include leaking clutch cover gasket ($6 and a couple hours to replace), and a bent kick start lever (fixed by a local welder). I push it pretty hard and it does well. The toughest nut to crack is starting it in the desert heat. Use the compression release, clean the cylinder and then open the throttle a couple of times, open the cold start valve, bring it up to TDC and kick from as high as possible. Have had first kick starts but normal is 3 to 4. Good Luck.