Nah.......Lots of guys are running over 100 hp with turbo's and/or NOS. The only ones that are reliable are the Rotax's. Lets use the motors that are making over 100 hp as useful information to help us know what motors will hold up N/A at 100+ hp.

I don't know of anyone running over 100hp in a new Raptor but the older 660 motor base started having major reliability issues after about 90 hp. I anticipate the new 700 motor base will have similar issues. Rotax's just have tougher cranks[img]i/expressions/face-icon-small-wink.gif[/img]

 

I'm sorry i thought we were talking cost not reliability. So then I agree with you. The Rotax is better design for high horsepower.

 

Thats right, now lets add up the cost of 100 reliable hp on a Rotax. Jed makes 100 hp with a stock bore and stroke DS. 12:1 piston, HPR CNC head, dual 38mm lectrons, HR5 cams and a 30 shot. He is around 77 on all motor and lets be conservative and say his 30 shot yields 23 hp. That adds up to about $5k in mods to get to 100 hp on the Rotax. Other than his lean spike at St. A's, he runs this thing regularly with reliability.

Can anyone come up with a single cylinder 4-stroke that has an engine base that is OEM for a sport ATV other than the DS Rotax that can reach 100 hp for less money and run reliably?

How does the theme to jeopardy go?[img]i/expressions/face-icon-small-happy.gif[/img]

 

I totally agree because Im making those same numbers with approx $3500 stock bore build. This is by far the most cost effective means to make reliable power.

GO ROTAX!!! [img]i/expressions/face-icon-small-happy.gif[/img]

 

Nobody knows how reliable a 700r is at 100 horsepower but i think it is safe to say they can make that power level with very little money. 3800 including drag pipes and nitrous when i priced it a couple months ago. Congrats to Jed 77 on gas thats impressive. I think that is the highest stock bore gas numbers I have ever heard.

 

I am confident if he had the newest cam grind that I have that he would break 80 hp. The new cam grind added 500 rpm of flat hp curve and 5 hp to my 800. It put me in the 90's!

 

What sprockets were you running and what gear did they pull this bike in to make 90hp?

 

17/42 in 4th gear as I recall.

What is even more amazing to me is the 730 I sold to Klug Racing is now on dual Mikuni's w/ superjets and is on 40% NM running a custom combination of HR4/HR5 grinds that complement the characteristics of NM and it pulled 96.5 on the dyno at 9800 rpm...........and that is with only 1mm oversized valves and their porting. Of course the plugs don't look great after only a couple passes at the track and they have to change the oil after every pass, but hey, thats NM.

Later

 

Yeah, NM will do that to ya every now and again.

What fuel was used to pull 90hp on your 800?

 

Well good job guys those are impressive numbers. Put them on the track and lets see what they run. If my 67hp can run 4.2 with a pilot then you guys should be setting some serious records.