Sent engine to yoshi and they claim it will have 53hp with a 41 mm carb. Talked to a kid there and he said he wasnt sure if it could beat a modded yfz-450. Why the hell did i send it in there?????????? What do you guy think??? The power to weight ratio would make the z a winner right?

It will definetly beat a stock yfz and only the fully modded race yfz's can keep up and/or beat it.I'm talking about the race yfz's like jeremiah jones or kory ellis,because your 450 is just about like doug gust.

Yeah, because yoshi said that it is the exact same set up as doug gust. So, hopefully i should beat them hands down. But the funny thing is the kid was talking about a yfz-450 that only had exhaust and airbox removed with a k$n . Hope full what he said was not true. I dont think it is.

I have a Yoshi 450 but it is not ported. I run an Edelbrock carb, full E Series pipe, and the stock ignition. In drag races up Sand Mountain in Utah it's a dead heat race with a pipe and filtered YFZ. Granted the kid on the YFZ was 130 lbs. soaking wet and my bro (who was riding my Yoshi) is 180 lbs. It beat a Honda 450R by roughly 9 or 10 quad lengths. My Yoshi will take my YFZ on the flat. The midrange is smooth and strong. You will like it for sure. I know mine is not at it's full potential yet. I will be getting it ported over the winter.

See for yourself...

http://forums.atvconnection.com/mess...did/417641.cfm

if you get your motor back and you can't beat piped 450's you deifinitely have something wrong. our stock bore non prted Z-400 beats them.

I can tell ya that some YFZ's are no joke. I've seen some stock bore YFZ's that just flat out HAUL!

yeah ive seen some stock bore 450's that are very fast as well.

Yes they do. They rev quick with that 5 valve head and titanium valves. Mine runs great with just a cam mod, needle, pipe, and filter.

Yes they are indeed very fast. I ran into one that had both HotCams, GYTR 13:1 piston, full ESR pipe, Ron Woods intake, Trail Tech -4 flywheel and ported head and it was VERY VERY VERY fast.

But you can have all the mods in the world but if the tuning is off or the setup is wrong it won't be worth a thing!