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racerx573
10-29-2009, 06:30 AM
Anyone get a chance to check out the new MX bike from Yamaha? It's probly the sickest dirt bike I've ever seen. The motor reminds me of a Cannondale, forward intake, rear exhaust. Maybe we'll be seeing this in the 2011 YFZ's?

So weird seeing bikes with no headers wrapping around. Looks like they went opposite of the CRF.

http://www.yamaha-motor.com/assets/content/images/600/10MS_YZ450F_wht_S1_c292b906.jpg
Ride1Rob
10-29-2009, 06:57 AM
Yeah this was talked about a few months ago. The intake now sits to the front (where it should be designed) and the exhaust is a straight shot to the rear. With that "Ram Air" effect this thing should rip!!! Hopefully they didn't do what they did to the head on the YFZR :ermm: .
Toadz400
11-01-2009, 08:08 PM
Originally posted by Ride1Rob
Yeah this was talked about a few months ago. The intake now sits to the front (where it should be designed) and the exhaust is a straight shot to the rear. With that "Ram Air" effect this thing should rip!!! Hopefully they didn't do what they did to the head on the YFZR :ermm: .

What'd they do to the head on the YFZ-R?

It's about time manufacturers started using this setup. Sure makes things easier.
Ride1Rob
11-02-2009, 05:58 AM
Originally posted by Toadz400
What'd they do to the head on the YFZ-R?

It's about time manufacturers started using this setup. Sure makes things easier.

The cams and the ports are a pretty good size smaller than the original YFZ setups. From what I've heard they're very hard to port and get any good hp #'s from doing so like on the previous year bikes. I'm thinking you don't have much room to open up on the casting before you damage the head but not sure. They have the GYTR setup that comes with bigger cams and ports as well. But that's the only place that you can get them and they aren't cheap.
sand45
11-03-2009, 01:05 PM
So the ports are diffrent than the 06 yfz...even smaller?
RosquistRacer39
11-03-2009, 07:22 PM
That new bike has a 4 valve head versus the 5 valve setup. All I can say is Bubba looked fast as hell on his bike at the us open of supercross a couple weeks ago. And the weird thing is the exhaust on that bike is far from a straight shot. It wraps around with a resonator built in. But I hope yamaha puts that motor in the yfz here soon and fixes the front end then I will buy one.
I loved my 04 other than the pushing in the turns, oh and when the crank busted the cases:D