Everybody did get lazy. The market dropped like a rock by the time the EFI models were released. I would be willing to bet that there are fewer EFI models out there than 03's. The economy tanked, and as it came back, it became all about the side by sides.
The rundown on changes by years is pretty much like this. 03 was the first year model. It's the only one with that 2 bolt chain adjuster, axle carrier, and swingarm. Also the only model without a removable rear grab bar. Different tie rod ends which necessitated a different steering post also. It had a black radiator and the fan didn't have the bladder like later models.
04 was just like 03, but had those changes that I already mentioned.
05-08 got a 1mm bigger carb with TPS, a different CDI and wiring harness. The cam specs changed but fitment is the same across all years. The clutch got bigger, and held a couple more plates. The frame was reinforced where the earlier ones had been having issues. The swingarm also got a little more reinforcement. They got magnesium engine covers which ended up being a recall on the mag clutch cover, and those got changed back over to aluminum. They got improved front shocks. I may have missed a thing or two, but I think that's most of it.
09+ got efi, and multiple changes related to that, like different cases to mount a different stator ect. The head changed, which has a straighter intake and different thermostat location. The body work changed and they got 1" wider a-arms, as well. That's all I know about, but I have limited experience with the efi model.
Tires, wheels, exhaust, bars, chain & sprocket fitment is the same across all years
The rundown on changes by years is pretty much like this. 03 was the first year model. It's the only one with that 2 bolt chain adjuster, axle carrier, and swingarm. Also the only model without a removable rear grab bar. Different tie rod ends which necessitated a different steering post also. It had a black radiator and the fan didn't have the bladder like later models.
04 was just like 03, but had those changes that I already mentioned.
05-08 got a 1mm bigger carb with TPS, a different CDI and wiring harness. The cam specs changed but fitment is the same across all years. The clutch got bigger, and held a couple more plates. The frame was reinforced where the earlier ones had been having issues. The swingarm also got a little more reinforcement. They got magnesium engine covers which ended up being a recall on the mag clutch cover, and those got changed back over to aluminum. They got improved front shocks. I may have missed a thing or two, but I think that's most of it.
09+ got efi, and multiple changes related to that, like different cases to mount a different stator ect. The head changed, which has a straighter intake and different thermostat location. The body work changed and they got 1" wider a-arms, as well. That's all I know about, but I have limited experience with the efi model.
Tires, wheels, exhaust, bars, chain & sprocket fitment is the same across all years
