Ive pretty much narrowed it down to the 2 atv's mentioned above but i would like some imput from you guys as well! I dont do any sand ( live in NC) mainly dirt drag racing, trail riding and the occasional top speed run. i love to powerslide on wet grass and stuff of that nature too. I was really leaning towards the Raptor but some people say the YFZ 450 would better suit me because its faster ( or so they say, idk lol), i already have a rancher 420 and really love that EFI.

oh, and i'd like to beat my buddies 05 predator too lol from a 20 roll or drag race!

 

Looks as if you answer your own question, the Raptor it is!

 

The 450 will be a little faster before it needs it's 100 hr rebuild but the 700 will have more torque and run well for 700 hrs . your choice.

 

100 hr rebuild? Ha ha, I don't think so.

They are both the best for their target. 450 is go go go. 450's are the race class, light fast wants to be rode hard. 700 is layed back little more comfortable with tons of power when you want it.

I always look at it as the 450 is the teen going crazy in the back yard. Wheelies, donuts, riding all out. The 700 is the Dad going out with him for a ride wanting to relax but, can still show him the powers there and he can if he wants.

 

The YFZ 450 uses the same motor as we use in the YZ450F we race don,t they? and no one goes over 150 hr before refreashing the top end . Some guys do it every 50 hrs. To get 500hr? maybe if we putt around the yard for 5000 miles.

Is the YFZ 450 version detuned vs the YZ450F motocross version?

here's two link to tell you when a 450 time bomb (any brand) needs a top end.
http://www.thumpertalk.com/forum/arc.../t-773261.html

http://www.allthingsmoto.com/forums/...st-rips-37880/

 

Na, I don't go for it. Both the links are the same I've ever came across. One just one guys opinion the other a "Kawasaki dealer" said Yamaha's need rebuilt.

I see tons and tons of 450's these days. I personally ride with 5. Two 2006, Two 2005 and my 2004. Mine was rebuilt by the owner previous to me around 2007. All other have not been. We easily put 100+ hours a year. All ride as strong as ever. I can't believe the literally hundreds i see at the dunes need rebuilt every 100 hours. Ya, know what i mean?

Now i can see if your a serious racer and you can't afford to lose even 1 hp you'll wanna rebuild. Some dragsters rebuild after ever 1/4 mile. Do they "need" it to make it down that strip again? No but, if it will gain them even a bit of extra hp and they have the cash it will be done.

 

That would be cool to hear at the track that a 450 is still running with 400 hr on it untouched.

When they make 450s with the same hp as 700 big bores there is a price to be paid somewhere.

 

I thought I should say I am not a racer. I do not ride at 6000-9000 rpm range every time I her out for hours at a time. I agree if I did I'm sure i would be sacrificing tons of power running on some (very) worn rings but, then again anything ridden like that would. Look at the 250 class and you'll see the same 100 hour mark.

I agree. I would say that even though you can go much longer than 100 hours it's not as mechanically resilient as other engines.

 

Just run that stuff ragged.. koopa is right if your not all about extracting the most power all the time you don't need rebuilds all that often. I had a 89 yamaha banshee I ran that thing till 2004 without a rebuild. Did it have power loss? HELL YEAH!! Did it still crank SURE DID!!

 

boduke, either one will take a 500Pred each machine having similar upgrades. The 450 requires more frequent valve adjustments and oil changes. The short skirt piston design also requires more frequent rebuilds. The 450s make similar power to a 700 by turning a lot more RPM and running in a higher state of tune. Both will work great for what you ask, I prefer 450s, but the 700 is a much more comfortable all day rider.