2010 Yz450f

As far as the 4 valve head, I heard that they produce more torque than the 5 valve does? Is that correct? Which I think is interesting because my '07 YZ450F seems to produce tons of torque. All though I haven't ridden other brands to compare it to.

I was just reading the Motocross Action article about the Husaberg upside down motor, and they state, "Other manufacturers(most notably Yamaha) will have their own spins on the slant engine design in the near future." MXA is pretty informed of pre production information, so this may confirm the new design.

If Yamaha changes the head to the 4 valve head hopefully they wont pick up the valve issues of the other manufacturers.

As far as the 4 valve head, I heard that they produce more torque than the 5 valve does? Is that correct?
No. The 5 valve would actually be more advantageous at lower speeds than 4. Torque, in the common vernacular, means low speed power, which is more a function of cam timing than anything else, although things like smaller ports and carbs help, too.
If Yamaha changes the head to the 4 valve head hopefully they wont pick up the valve issues of the other manufacturers.
Their problems are because of poor material selection and poor execution of the manufacturing process. The exhaust valves in a YZF are as big as any of their competitors', yet the blue bike has no problem with them to speak of.
I was just reading the Motocross Action article about the Husaberg upside down motor, and they state, "Other manufacturers(most notably Yamaha) will have their own spins on the slant engine design in the near future." MXA is pretty informed of pre production information, so this may confirm the new design.

i think it was confirmed a long time ago with the pictures....

Yeah your right, I was just adding additional info to this thread that I thought might be relevant.

Yeah your right, I was just adding additional info to this thread that I thought might be relevant.

cool, i see

I'd love to see some of these changes applied to the two strokes bikes as well... direct injection and no more dented pipes ? sounds good, im sure those engineers in japan could figure a way to do it.

I'd love to see some of these changes applied to the two strokes bikes as well... direct injection and no more dented pipes ? sounds good, im sure those engineers in japan could figure a way to do it.

that ain't gonna happen anytime soon until the demand for 2 strokes comes back.....and I wish the demand would come back....4strokes sure are very costly to maintain over time

...no more dented pipes ?
You're imagining an entire expansion chamber coiled up in the space currently occupied by the air box??

Yamaha dealer show is Sept 8th. We will find out then what is real and what is fake. Heres hoping for real.

Maybe someone had took pictures of James Stewart first ride on the 2010 :-)

Talked to James Stewart Sr. and he confirmed that the 2010 yamaha is one bad bike !!!!!!!!

I'll take one!

There have been meetings about that photo

I'll bet there have....:worthy:

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