Next brand on turning backwards the engine

The engine in a YZ is not backwards.....just the head is reversed....
look at it this way.....a V8 has 4 cylinders where 1 head "the right way" and the other head "backwards"....think about it...
Oh and the way the 250F Yamahas looked yesterday....it made the competition look like they were going backerdz...haha....
my guess it will be Suzuki on the 250F...or KTM......

The 250 Yamaha's seemed to have a lot more power than all the other brands, the 450's not so much

Cracks me up. I'd say 75% of the yahoos on here last year were blaming the engine design for the evil handling of the Yamaha.

So many engineers on Vital!

Can't remember where I saw it but it was an Yamaha engineer talking about the rearward slanted engine being an evolutionary requirement to get straighter intake tract than was possible with the airbox located under the seat. in order to straighten the intake any more using a conventional design you would have to raise the airbox and boot, making the seat height taller. That the performance of the conventional design was pretty much maxed out, moving the airbox to the front allows a downdraft type intake design that open the door for greater performance... That being said other manufactures are surely looking for ways to incorporate the downdraft design into their engines also. There are only so many ways to solve the same problem, so I think reversed heads could be coming from other bike manufactures.

And doctors, and race officials, and team managers, and PED experts, and...

how much more power do we need on 450's?

all i know is the way they are blowing up , gearbox going after 3 hour s left right and center here, i hope they get the relibility sorted , strange cause yamaha use to always have a bulletproof , two guys i know have snaped a rod , and both seized there bikes , with under 6 hours on them , seem like a great bike when there going tho

i think you put Martin and Webb , on any brand of bike they would have been were they were yesterday , but they were very impressive off the start , them JGR bikes have been that way for the last 3 yrs , when people were giving out about them , loads of HP , the handling seems to be better on them with the new model tho

It wont be Honda, they built a prototype 'backwards' engine but decided not to Productionise it ...its all in a interview in a New Zealand motorbike magazine with the guy who is in charge of the CRF programme, he also talks about the CRF's being built for the masses (hence the reason why they are a bit more mellow than others power wise), and the fact that its unlikely there will be a 2-stroke MX bike in the future but of course did not rule it out.

Good on Yamaha riders getting 1st and 2nd overall, to say in one race it means they are the best bikes out there is funny, so if they dont win next week are they crap?

Lol,that's a pretty cool factoid.

Isn't there a European bike that is a 2 stroke with a rear exhaust? Ossa?

Honda already had a backwards topend


Soichiro Honda's First proper motorcycle - the Model D, the "Dream" 1949. 98cc two stroke. 2 gears.

Many folks (announcers - some of which are ex-racers, riders, etc) have been talking about the JGR Yamaha horsepower all year since they rolled out the 2014 450s. They sure looked like they had plenty of HP in the first moto yesterday by pulling the top 2 spots coming out of Talladega. Reviews for the 250Fs have been stellar and reviews for the 450s have been mixed (most say the bike is vastly improve from the previous 3 years but still not quite right). Sooner or later Yamaha will get the 450s right is my guess. That said, 99.9% of the riders on the planet aren't good enough riders to use all of the HP out of a bone stock 450 (of any manufacturer).

Did you not see the JGR bikes go 1-2 on the first lap of the first moto?

I have a 14 yz450. It has too much power. I'd imagine they don't do much too the race engines anymore for more HP. Probably better/smoother/longer power. Its been an adjustment making sure I dont get too crazy with the throttle. I rode a half mile wheelie on it like nothing just massive over the top roll on and also top end pull. Insane lol

To clarify I believe the first yz400 had 43 HP. The yzm was said to make 60 HP that henry rode. That's 17 HP. I bet a works yzf nowadays is within 5 HP peak of a stock engine with pipe and VP fuel. Much closer gap. One thing is for sure and that's our four strokes are much closer in production to the works engine than a two stroke ever was. They really are a works bike for the masses. Now if the maintenance is closer to a racers budget idk what people expect with bikes than run so hard. Is what it is I definitely can't ever see my 250 2t ever being my primary bike again. God does it feel slow lol

I just thought of something with the Yamaha. The seat/tank design. Remember who designed THAT? Does JS7 get credit for fixing the Yamaha, and messing up the Suzuki at the same time?

Yep! Hahaha...