Last fall I picked up a used 04 KFX 400 that was in excellent shape and over the past three weeks I did 8 days of riding in the Imperial Sand dunes, Dumont dunes, and Ocotillo Wells Desert in S. Calif. Here are some inputs on the performance of the 400 compared to a 04 Raptor 350 that I have been riding the past two years.

On the Raptor 350 I had changed the sprockets to 12/40 (stock is 13/38) to gear it down to allow slow travel over rough mountain trails and it worked perfect for this. However on the dunes, the Raptor 350 was somewhat lacking when climbing steep dunes. I would run out of power in third gear and when I shifted to 2nd, I would spin out. Second was too low to start on the dunes since I would not have the speed (in this case the stock sprockets would have been better).

On the KFX 400 I changed the sprockets to 12/44 (stock was 14/40) to again gear it down for low speed riding on rough mountain trails. When I rode it the first time in the dunes, I notice a big difference between the 400 and the Raptor 350. The KFX 400 had way more low end torque and it really worked great on the dunes. I was impressed. Also in the desert on rough trails the low speed in first gear was great. So I am pleased with the performance of the KFX 400 over the Raptor 350. The 12/44 on the 400 did cut my top speed down a lot to about 40 mph which is fine with me. I am not a high speed rider. Fact is on an ATV I feel unconfortable at speeds up in the 35 mph range (I have an add on speedometer on the 400). Maybe my age, 63, makes me a slow rider??


I have decided that if I rode dunes only with the KFX 400, I would probably be better off with 13/44 sprockets then the 12/44. However since I ride both dunes and mountain trails I am pleased with the 12/44 ratio.

Maybe the above info will be helpful to someone that is thinking about changing sprockets or going to a 400

 

wow!!! you did gear that puppy down. im glad you like the kfx, i love mine. i trail ride and ride in the sand, i went 1 tooth down on the front sprocket and it gave it some great low end power. it took a little off the top but you really never do open them up all the way . when we race its only a 100 yards , so it gives you a great hole shot.

 

Hey guys, whats going on I just bought 06 KFX 400, I like it I have only rode for break in though. I am going out today at 1:00 to ride. What do you guys think of the power and speed I have not really opened it up yet.


Thanks,
Bryan