it is not a kevlar sleeve and no it's notresleeved.
it is actually just like a 2 stroke cylinder, its nikasil plated. i could tell you how i got 470cc's out of this motor, but then it wouldn't be my secret anymore. if anyone wants thier yfz to be 470 contact me by email or PM me. i can give the details to serious people.but i know i'm the only engine builder right now offering any kind of motor mods to this machine.half the people like trinity aren't even done building pipes for it let alone doing the motor work. i let them worry about exhaust and i worry about the real performance mods.

 

You guys actually believe that you will be able to get the same horsepower out of a modded 470 as a modded 727? You obviously flunked physics. Sorry guys, but there isn't a transmission or gearing combo out there that can make up for 200 + CCs. I really wish one of you with these tricked out YFZ's would show up down here. So far we have seen only lightly modded ones and they can't even hang with a high-compression stock bore raptor.

~HoundDog

 

You guy's hav'nt learned yet........All Raptors are slow.........Till race time!!!!![img]i/expressions/face-icon-small-shocked.gif[/img][img]i/expressions/face-icon-small-happy.gif[/img][img]i/expressions/face-icon-small-cool.gif[/img]

 

so you're saying that i could never make as much power with a smallblock as you can with a big block, well don't ever tell the PRO 5.0 race guys that. becuase they all run smallblock fords that run 6.7 second 1/4 mile times. how many bigblock mountainmotor prostock guys you see running those numbers? only a handful.


don't say that a yfz can't make as much power as the raptor. cause stock for stock the raptor has a 220cc advantage, and makes 3-4 hp less then the yfz.then add up the mods.
raptor with, good pipe, airbox mods, jetting = 45-47 Hp.
yfz with exhaust,airbox mods and jetting = 47-49 HP.

it looks pretty equal there so far,
then start adding cc's
727 raptor tuned perfectly 60+ hp. this will vary between each machine. one might be making 60 then next 65. so we'll just call it 65 hp for a 727 rappy.
470 cc's for the yfz with no head porting or carb mods other then jetting has gained us over 60 hp.
the yfz's 60 Hp will beat the raptors 65 hp in a drag race everytime,especially in the sand. remember the wieght difference and the rpm difference. wheel speed is what wins races in the sand.
where traction is much better in the dirt it would be a much close race given the distance being raced.
theres always many variables in a drag race.
but to say that the yfz is not going to be as fast or faster then the hopped up raptors, would be very uneducated.

 

killerkx327 I would like to have a friendly race at St Joes some time against the 470. I'll bring my 60hp DS. I know I'm at the disadvantage weight wise but the schools buses (Bombardiers) seem to like the sand.

Just let me know.

J Ross

 

THEBOMB,
that would be great, i have no problem with friendly races, win lose or draw it's all fun and games til some one loses then it's hilarious .
i've never been to st. joe's but i've heard some good things and have wanted to come down that way. i might just have to do that. send me an email so i can keep it on hand for when the time arrives that i can make it down there.
do you know of any reasonable hotels to stay at or anyone who would let me stay in the driveway LOL.

 

The pro 5.0 guys are running turbo and supercharging. The pro stockers are natural aspiration and carbs. They have to supercharge because that size can only move so much atmosphere at rpm limits. I will stand by my statements: more inches can make more power. That's why you don't see 125cc 4 strokes winning at competition hill. 450s are fast. 660s can be faster. Look at your analogy with pipe jet and airlid--you didn't take into account the raptor is 9.4-1 and the YFZ is 11.9-1. What if that were the other way around---low compression 450 and high compression 660? Raptor would be huge ahead.

No offense, I like this discussion. I got rid of my 460 Fairlane and now I own a 5.0 Stang. I like the smaller more efficient units that are lighter but give props to bigger inches. [img]i/expressions/face-icon-small-cool.gif[/img]

 

stick with the Raptor.... you wont be dissapointed!

 

killerkx327 let us all know when your planning on coming to St Joes. Maybe some of the other forum menbers would like to play a little too.

There's never a problem with getting a race there.

J Ross

 

well as soon as i can get some free time, summer is a very busy time for me.
like i said before i've always wanted to come down there, so as soon as i can schedule a time, it may be within the next couple months.