It's Here...the 2010 YZ450F

Anyone see any hard info regarding split oil supplies or wet vs. dry sump?

1.2L dry sump...From the pics and cut outs it appears to be shared supply...:busted:

although it does look like it has a sight glass instead of a dipstick...right where mud builds up...lol

Usually FI means metal gas tank. Thats a couple pounds right there. And I do wonder about the hotseat...?

Usually FI means metal gas tank. Thats a couple pounds right there. And I do wonder about the hotseat...?

It says that it has a semi-translucent tank so you can see the fuel level easier.

tank is plastic , i think the rmz is the only bike to use a metal tank but i could be wrong. i dont really follow any other brand besides yamaha and a few off brands like husky...

I'm an off-roader so i'm anxious to see who puts out the first big tank and what it looks like! Bring on the 18" wheel and a headlight too!

Correct. Yam, Kaw and Honda have plastic tanks. What is the bulbous thing at the beginning of the header right as it comes out of the cylinder? Must be the resonator? Function?

tank is plastic , i think the rmz is the only bike to use a metal tank but i could be wrong. i dont really follow any other brand besides yamaha and a few off brands like husky...
1.2L dry sump...From the pics and cut outs it appears to be shared supply...:busted:

Source?
Usually FI means metal gas tank.
It says that it has a semi-translucent tank so you can see the fuel level easier.
I wonder what sort of metal they have that's translucent. :thumbsup:
I'm an off-roader so i'm anxious to see who puts out the first big tank and what it looks like! Bring on the 18" wheel and a headlight too!

Me too, in fact, with a 1.6 gallon fuel tank the bike is almost unuseable for me. I think that IMS and Clark are going to have to get pretty creative to increase the fuel capacity with the tank being located where it is.

Does anybody know if FI bikes are significantly more fuel efficient?

Yamaha states: "Yamaha FI provides optimal air/fuel mixtures in all altitudes and wide range of temperatures for outstanding throttle response."
All FI systems do that. Actually they pretty much have to, to work at all. O2 sensor is completely useless in racing machines like this, it would help cruise, but since when anyone does that with an mx bike? It's all about pre-set maps. Only thing it could learn is some throttle enrichments and stuff, but those depend more on the rider specific "taste".

Now what I find interesting is the long intake. Exhausts have been tuned to give maximum power for ages, but on the intake side there has been no room for that really. New Yamaha seems to have "tuned" intake. It'll sure be interesting to see how much juice you can squeeze out of these.

Off-center crank pin is not about "forces" or something, it's all about cylinder gas exhange and piston speed. Together with cam-profiles, tuned intake and exhaust this should really be one impressive engine.

The engine design is like a Ducati with no front cylinder...

Me too, in fact, with a 1.6 gallon fuel tank the bike is almost unuseable for me. I think that IMS and Clark are going to have to get pretty creative to increase the fuel capacity with the tank being located where it is.

Does anybody know if FI bikes are significantly more fuel efficient?

are 450 that thirsty? i ride a yz292f big bore and stroked and its not to thirsty. im pretty agressive and race in the A class ... i have a big tank on it 2.6 clark but i think if i want to i could get by on the stock 1.8gallon tank for the majority of my races..

Me too, in fact, with a 1.6 gallon fuel tank the bike is almost unuseable for me. I think that IMS and Clark are going to have to get pretty creative to increase the fuel capacity with the tank being located where it is.

Does anybody know if FI bikes are significantly more fuel efficient?

It could, but a really well jetted carb isn't bad.

Did you notice it has a 110w alternator? :busted: At the least, that indicates a much larger potential output than the Gen 2 bikes could dream of.

Does anybody know if FI bikes are significantly more fuel efficient?

They can be. My WRR was pretty darn efficient, but after changing the map for max offroad, it drinks it pretty good.

Did you notice it has a 110w alternator?

The stator looks to be fully wrapped. 110W is good for two 35w HID :busted:

However, looking at the reg on the bike, I bet the bike is setup to run on AC only. If that is the case, there goes the HID as they need DC power only.

I wonder if the bike can be wired for both? or just DC?

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Off-center crank pin is not about "forces" or something, it's all about cylinder gas exhange and piston speed.

Actually, it's about exactly that. Offsetting the cylinder as has been done here clearly reduces piston skirt thrust. It also allows the use of a shorter rod while maintaining the less acute rod angle of a longer one, which is about piston speed, as you say. Longer rods are generally a better choice for high RPM power, as is a more over-square engine (bore larger than stroke), which was also done here. Offsetting the bore is another way to arrive at the same result.

Discussion of rod length/angle (section 3 of the post): http://www.thumpertalk.com/forum/showthread.php?p=6844321#post6844321

My local dealer said their phone rang off the hook this morn just for this bike.

A lot of us RMZ F.I. guys have reported lower fuel mileage compared to carbs. But the stock mapping, as it turned out, was very rich. I believe f.i. gets lower mileage overall, and it also currently produces less power per liter in mx bikes according to guys like Ron Hamp and Sisneros.

are 450 that thirsty? i ride a yz292f big bore and stroked and its not to thirsty. im pretty agressive and race in the A class ... i have a big tank on it 2.6 clark but i think if i want to i could get by on the stock 1.8gallon tank for the majority of my races..

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