2009 R1 might not be the prettiest looking bike, but

Yamaha FJR Motorcycle Forum

Help Support Yamaha FJR Motorcycle Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

Toecutter

What would DoG do?
Joined
Jun 13, 2005
Messages
6,202
Reaction score
20
Location
Fresno, CA
until I talked to the local service manger today, who was at the Vegas trade show this weekend, and even got a picture taken with V. Rossi.

He said the new R1 sounds more like a Ducati than a Yamaha, because of its revolutionary crank design, Crossplane. The torque bursts supposedly hit differently on the crank, enabling the rear tire to recover and reshape evenly through the turn, theoretically allowing more power to be smoothly applied to the ground, or some such techie stuff....

1400 c.c. Gen III Crossplane FJR anyone? (if'n we can't get the V-Max motor)

From the website:

Introducing the 2009 YZF-R1, the first ever production motorcycle with a crossplane crankshaft. Crossplane technology, first pioneered in MotoGP racing with the M1, puts each connecting rod 90° from the next, with an uneven firing interval of 270°- 180°- 90°- 180°. This all but eliminates undesirable inertial crankshaft torque, which allows the engine’s compression torque to build smoothly and provide a very linear power delivery out of the corners. It’s a feeling that’s simply unmatched, like having two engines in one: the low-rpm torquey feel of a twin with the raw, high-rpm power of an inline 4. In fact, the new YZF-R1 is not a continuation of existing supersport development; it is breakthrough technology that represents a paradigm shift in both technology and performance.
 
I look forward to someone explaining that in terms that I can understand. :blink:

 
Racetrack Big Bang technology finally makes it to the street. Should be interesting!

Too bad it's such an ugly duckling.

 
I look forward to seeing many piloted by riders who can barely ride them to 50% potential. B)

 
I recently saw that too, looks very interesting. I saw a pic of it, thats all you need to see to understand it. I'll see if I can dig it up.

 
A good pic and summation from a Member on ST.N

09SPBK_YZFR1_blue_D1_002_7bc2bfdc.jpg


The 2009 YZF-R1 sports real M1 technology, which

puts each connecting rod 90° from the next, with an uneven firing

interval of 270°- 180°- 90°- 180°

 
until I talked to the local service manger today, who was at the Vegas trade show this weekend, and even got a picture taken with V. Rossi.
He said the new R1 sounds more like a Ducati than a Yamaha, because of its revolutionary crank design, Crossplane. The torque bursts supposedly hit differently on the crank, enabling the rear tire to recover and reshape evenly through the turn, theoretically allowing more power to be smoothly applied to the ground, or some such techie stuff....

1400 c.c. Gen III Crossplane FJR anyone? (if'n we can't get the V-Max motor)
A buddy of mine sent me this link, showing what the engine sounds like while accelerating and while in a high speed fly-by.

https://www.youtube.com/watch?v=ZPsEm2XASmM...feature=related

judge for yourself, but this must be one of the most beautiful sounds I've ever heard-more like an F1 car than anything!

 
Digging through my magazines I found an article in Power Bike giving a run down on the inline 4 crank configurations. According to PB the design the new R1 uses was originally specific to the M1. It delivers a 'long bang' torque profile within a 720 degree cycle. The pulses come with the first 2 in rapid succession followed with the rest trailing off and the fifth and final pulse eventually 540 degrees from the first.

The 'big bang' , which is used primarily by the Kawasaki Moto-GP bike, has three pulses within the 720 degree firing cycle. Each pulse has two pistons firing at once. Lots of torque, good traction, but very hard on the drive train.

The long bang with it's initial rapid succession of pulses trailing off to a longer intervals gives the tire a chance to stay hooked up and maintains a fairly smooth power delivery. This is also the only crank configuration that does not have the pistons aligned at 180 degrees (V4s excepted).

1400 c.c. Gen III Crossplane FJR anyone? (if'n we can't get the V-Max motor)
Given I'd never be able to take advantage of the full capabilities of the new R1 (or any R1) Toe's idea would be something I'd really look forward to.

 
Last edited by a moderator:
The torque bursts supposedly hit differently on the crank, enabling the rear tire to recover and reshape evenly through the turn, theoretically allowing more power to be smoothly applied to the ground, or some such techie stuff....
The "tire recovery time" theory is starting to die off. I don't want to try to disprove it since I think there's something to it, but I've heard it's not what's actually occurring.

The main benefit to the cross-plane crankshaft is the conservation of kinetic energy. On a flat-plane crank all four bouncy bits stop completely twice a revolution, which means the crank and flywheel mass have to jerk them all back the other direction at the same time. The amount of energy needed to do that increases with revs and can be close to the engine's total torque output at the revs GP bikes are running, which makes for horrible spikes and valleys in the resulting power output. With the cross-plane crank, half the bouncy bits are at 100% velocity when the other half are stopped. Even though the pistons have to be ****** back the other direction, it's only half as many and the other half are helping the crank's mass to do it. The downside to the cross-plane is that it requires balance shafts to control the wobble, the crank's no longer symmetric and the ends want to travel in circles out of phase with each other. You can see the lobes for the counterbalancers on the front of the engine. Traditionally, this extra spinning mass has made the crank too heavy for racing use, but as revs go up needs change.

engine.jpg


Yamaha's BSB team messed with changing the cam timing to make the engine a "big-bang" (180-180-180-360, where two cylinders fire on the bold), so far as I know they ran it for part of a season and dropped it. I think Kawasaki's GP engine uses that or maybe even a "double-twin" crank and, well, the results speak for themselves. :)

 
Last edited by a moderator:
Top