hey guys wuts up,
i have 2 sportsman 400's and they out drag my uncles sportsman 400. I dont understand this because we got ours about 1 week part from eachother, and he does a little more rirind then me , so i would assume that they would go the same speeds. He owns a horse ranch, and we always take our toys to the horse track and race them. I dont no y but i always beat him by at least 7 quad lenghts on the straight away. I am 15 years old, 6'5, and 210 lbs. My uncle is 44, 6'5, and 220 lbs. This is y i dont get y i always beat him. I actually had my little cousin who is 11 years old race me on my uncles 400 and i still killed him by about 6 quad lenghts, and he ways about 100lbs. My friend also has a sportsman400 and i beat him all the time also, he weighs more than me. My spoortsmans are completely stock. I raced a Vinson 500 and even beat that. When i raced my friends dads sportsmanX limited edition, he only beat me by about 4 quad lenghts down the straight-a-way on the track. I not sayin this is a bad thing but i wonder y there is such a speed difference in my 2 sportsmans compared to others. i just though id ask and see wut u guys think wut the deal is.

MuDsLiCa

 

hmm this is an odd one they should run the same but there is a little technic to racing automatics it depends on how ya set on em.
Like if you sit on the very back end and lean down you will go faster because you a more arrowdynamic and you catch less wind. So that could be part of it if you know how to race em. But I really have no clue unless your uncle got screwed.

 

Not true, I have bought 2 machines the same day, and have had one alway's a little stronger than the other....

These are not hand made,as two will always be different...and of course if you bought them from different dealers it could have a different set-up than yours.

If you really wanted to get into this..I would compair and inspect the clutches, belt CTC.and complete jetting...
If that all checks to be identical,do a compression test.

I have found that most of the time the 2 ATV's are set the same and have the same spec's, but one would alway's run away from the other..but not by a huge margin..

Try having you uncle race you on your ATV and you on his...as I think you might have gotton a hole shot on 11 year old...
Have any inside info a the Sp400?? I just bought a Blue one yesterday for my son..have a 500 HO but don't know what to expect from the 425cc...

 

the sp400 is a great machine, its gotten me everywhere i wanna go and back. the touque is pretty damn good considering that i pulled down a tree in the woods with it. Speed is fair, mine go about 61mph. the ride is great, smooth as anything. best mud, trail, and overall riding machine iv even seen for its caliber. so i would have to say the sp400 is a awesome machine.

 

I have to agree with Sagecrusher, no two machines are alike and It can all come down to the assembly process, tolerances, etc. Sometimes the clutches are not aligned perfectly but good enough to pass and could be improved upon, same goes with the jetting, most machines are jetted rich to compensate for different climates, but I think it impossible to jet every machine the same and have the same outcome because there are so many factors in the assembly and machining processes and tolerance ranges that no two can be the same or any of them perfect. Motors will vary and the carbs will vary, the clutches etc. everything has a tolerance and sometimes they stack and cause problems. I work in the assembly and manufacturing of forklifts, so I see this every day. The best thing to do is to learn about your machine and exactly how you can dial it in to run the best it can. A repair manual, Olav Aaen's clutch tuning book, and atvconnection are the things you need to help you learn.

 

And also listening to NC Scrambler's words of wisdom, as he has given me very usefu,l and knowledgeable Information....[img]i/expressions/face-icon-small-happy.gif[/img]