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14 Posts
I'd like to preface this by saying that I am very interested in the 2009 R1 and it's likely that I'll be buying another bike this year. If so, it'll most likely be the R1. In white.
Now I'll just come right out and say that I think the crossplane crank is mostly just marketing hooey. I come to this conclusion based on automotive road course racing and general domestic V8 knowledge. I acknowledge I don't know everything, so I'd like to hear some feedback (positive or negative) and open this up for discussion with the more mechanically inclined.
I think there's a lot of hype and mystery surrounding the R1 and it's crossplane crank. If you look at V8s, most are crossplane setups. Ferraris and many racing engines are flatplane. Look at the two firing orders of V8s, and just cut them in half to form an inline 4.
The reason most V8s are crossplane is because they have less vibration issues with harmonics. The downside is that they have an uneven firing order, with two cylinders on each bank firing next to each other. So you have exhaust from these two cylinders fighting each other, trying to occupy the same space without enough time for the first cylinder's exhaust to move out of the way of the second cylinder's exhaust. Same issue with the intake, only reversed. Put individual throttle bodies on the intake and 180 degree exhaust (like the GT40's "bundle of snakes" or just hot rod style zoomies), and you no longer have the inefficiency issues of a crossplane V8.
Ferraris and most ground-up built racing engines use a flat plane design. This is what gives them their buzzier sound (like two motorcycle engines connected at the crank, because that's essentially what it is) compared to the domestic V8 sound with it's more uneven pulse sound (the muscle car sound). You have better exhaust and intake characteristics, and drivers prefer the smoother torque delivery. There won't be a large difference in power development between the two engines if both are well designed, but they sound drastically different and there's the driver's supposed preference (I've driven but never really pounded on a flat plane V8, so I can't personally say). These engines aren't common in street cars because the frequency harmonics makes them vibrate much more than the common cross plane V8.
Firing order: 1-8-3-6-4-5-2-7
I think it's odd that automobile racing prefers a flat plane, and Yamaha is touting their cross plane crank as being the better style. I honestly don't think it'll make a damn bit of difference on a street bike. But it'll definitely sound different than the other I4 sportbikes. And that's why I want it. I can easily catch up to the Suzuki's power levels with cams. A little nitrous would be great; I really hope to avoid turbocharging another bike.
P.S. If I had the equipment to make my own crankshaft and camshaft, I'd build myself a flat plane V8 in a heartbeat. Because they sound cool. :lol
Now I'll just come right out and say that I think the crossplane crank is mostly just marketing hooey. I come to this conclusion based on automotive road course racing and general domestic V8 knowledge. I acknowledge I don't know everything, so I'd like to hear some feedback (positive or negative) and open this up for discussion with the more mechanically inclined.
I think there's a lot of hype and mystery surrounding the R1 and it's crossplane crank. If you look at V8s, most are crossplane setups. Ferraris and many racing engines are flatplane. Look at the two firing orders of V8s, and just cut them in half to form an inline 4.
The reason most V8s are crossplane is because they have less vibration issues with harmonics. The downside is that they have an uneven firing order, with two cylinders on each bank firing next to each other. So you have exhaust from these two cylinders fighting each other, trying to occupy the same space without enough time for the first cylinder's exhaust to move out of the way of the second cylinder's exhaust. Same issue with the intake, only reversed. Put individual throttle bodies on the intake and 180 degree exhaust (like the GT40's "bundle of snakes" or just hot rod style zoomies), and you no longer have the inefficiency issues of a crossplane V8.


Ferraris and most ground-up built racing engines use a flat plane design. This is what gives them their buzzier sound (like two motorcycle engines connected at the crank, because that's essentially what it is) compared to the domestic V8 sound with it's more uneven pulse sound (the muscle car sound). You have better exhaust and intake characteristics, and drivers prefer the smoother torque delivery. There won't be a large difference in power development between the two engines if both are well designed, but they sound drastically different and there's the driver's supposed preference (I've driven but never really pounded on a flat plane V8, so I can't personally say). These engines aren't common in street cars because the frequency harmonics makes them vibrate much more than the common cross plane V8.
Firing order: 1-8-3-6-4-5-2-7


I think it's odd that automobile racing prefers a flat plane, and Yamaha is touting their cross plane crank as being the better style. I honestly don't think it'll make a damn bit of difference on a street bike. But it'll definitely sound different than the other I4 sportbikes. And that's why I want it. I can easily catch up to the Suzuki's power levels with cams. A little nitrous would be great; I really hope to avoid turbocharging another bike.
P.S. If I had the equipment to make my own crankshaft and camshaft, I'd build myself a flat plane V8 in a heartbeat. Because they sound cool. :lol