how yamaha is the only one that made a cross plane crankshaft R1 info

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very interesting video I found about yamaha being the only manufacturer of a cross plane crankshaft for the R1..... many interesting points in this video us xs650 guys will knowtice and even the RE phase guys will appreciate .... I knowticed the number 270 degrees while watching and then decided to share it here, you have to have a real mechanical mind and some patience to watch then entire video, but being a moterhead or gearhead myself I found it VERY interesting, YAY Yamaha!

(475) CROSSPLANE inline 4 EXPLAINED in detail - How the YAMAHA R1 i4 differs from all other INLINE FOURS - YouTube
 
i do belive all automotive and all boat and all industrial... im sure someone will voice in with a answer on that ....i would assume someone like Ferrari or somebody like that would have also done something like this.. but according to the video's yamaha is the only one and the R1 is the only bike they did it in.... I'm sure it costs 20 times as much to make a 4 way solid crankshaft instead of a flat plane
 
Ive been a mechanic for my entire life, came out of the womb with an adjustable spanner wrench (crescent wrench) and I have never seen one, EXCEPT! drum roll,,,,,,,...... when the rotary guys build a 3 rotor engine they add a crankshaft extension,,, except its actually a eccentric shaft... and when they do its separated 360 degras divided by 3.. not a flat plane and also not a cross plane... harder to explain than I thought lol
 
jetmechmarty said:
Don’t triples fire every 120 degrees? Laverda Jota being an exception?
Click to expand...
Early Jotas had 180 degree cranks , 2 up 1 down kind of deal. Later Laverda triples had 120 degrees, just like BSA/ Triumph triples. The 270 degree twin was first suggested by Phil Irving, and I believe Bill Nourish in the UK revived the idea for his 8 valve Triumph twin engines. Which were based on the earlier Rickman/ Weslake head design, and so on.
In general, 99.99 percent of I4 engines have a flat 180 degree crank, since it gives perfect primary balance and no rocking couple. As far as I understand, the main advantage of the Yamaha R1 crossplane crank is better grip out of corners, basically mimicking V2 and V4 firing intervals in a more compact and easily manufactured I4 configuration.
 
Not sure if it has bearing on this ..but liter bikes are climbing in power they get out of them
The boys says it is on the expense on the torque curve --- not being as flat anymore
So when things are going fast which they do on these bikes
There is a lot for the brain to keep check on Apex Brake point the riding
With a " Spiky " power band there is the need to have the exact right gear otherwise it is not so fast on the exit
And that can be to much for a regular enthusiast.
On bikes a couple of years older you are actually faster as a " Non professional "
is the word. Speaking of a track or curvy road . But I suppose the top power is a sales argument.

On a side note i Remember when i saw the R1 first time. I was at the dealer ,Believed it was a smaller bike
It was small in size did not look as a King having that much power for those days standard.
The then co owner of the dealership came by. He said if you was 18 years old living in
cities and had a full insurance No bonus ...A year and the insurance cost would be the same as the bikes purchase prize.
They crashed and the prizing was aimed at not having these customers.

He also told he had an experienced customer who bought one and came back wanting to swap to something else
He was out at the highway at cruising speed ca 120 Km / h should overtake and went out to the left lane and gave
full throttle . I don't think he downshifted
The R1 roared up on the rear wheel at that highway speed .. He managed to catch it before flipping over.
100 -- 200 miles then he decided for something else
" I cant have a motorcycle like this ill kill myself "
 
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