Super Tenere Engine: Crossplane?

[YamahaCruiser]

Is the Super Tenere really a crossplane engine? I was listening to the growl today as I opened it up a bit, and the thought kinda crossed my mind: Is this a crossplane, because I can kinda hear a similar sound to what the FZ-10 was making in some of the review videos I was watching. If so, what the heck is the crossplane engine actually doing for me? I am kinda looking for an "explain it to me like I'm 5" answer, haha. Thanks.
"

 

[jmcgilroy]

http://www.motorcycledaily.com/2013/07/new-yamaha-crossplane-twin-revealed-at-japanese-meeting/

By the way, I know less than you do on this topic... I'm putting myself to bed without dinner!

 

[2daMax]

My understanding of the parallel twin Crossplane is that the crankshaft angle is 90 Degrees between each connecting rods vs 180 degrees like on a Versys. The firing cycle is 270 degs making the exhaust sound similar to a v-twin.

If you put a In-plane crankshaft on a table, both of the section that connects to the connecting rods will lie on the same plane. For a Cross plane crankshaft, one will be on the table surface and the other 90 degrees standing up.

 

[Scubatech]

You are correct from what I have read on this subject.

 

[Mark R.]

Crossplane cranks are usually referring to 4 cylinder in-line engines, but Yamaha refers to the ST engine as "Crossplane." From their web site: "Crossplane Crankshaft Engine
The 1199cc parallel twin, liquid-cooled engine features a unique 270° crossplane crankshaft for superior traction. It’s almost like having a big-bore thumper without the uncomfortable vibration." The reason for a crossplane engine on an in-line 4 is to change the power delivery characteristics for superbike and MotoGP racing so the tires stick better on the pavement. For our bikes, it is to give a "thumper-like" power delivery for ease of off road riding. Which is really the same thing, if you get right down to it.

Mark R.
Albuquerque

 

[YamahaCruiser]

Thanks for the replies. I was unsure if it was a real advantage in our twin bikes, or just marketing buzz words.

 

[88millimeter]

It is a crossplane, and the benefit of a crossplane parallel twin is that because the firing order is 270 degrees apart there is a long pause between power strokes of the cylindes, which means if the tire loses traction on one power stroke there is a long time before the next power stroke which allows the wheel to regain traction. Of course "long pause" and "long time" is relative to a conventional engine, in reality this process occurs in fractions of a second.

 

[jbrown]

I think the potential gains for crossplane inline engines are more complicated than changing the power pulse spacing. On a flatplane inline engine all the pistons stop and reverse direction at the same time. In a crossplane inline engine, half of the pistons are at their maximum speed while the other half are stopping and reversing. The claim is that this changes the torque load characteristics in the crank as the energy is transferred back and forth between the pistons and the crank. It can have power delivery benefits, and it can have benefits in longevity of the components. I don't know if the Yamaha implementation actually realizes any of those potential benefits.

http://www.ashonbikes.com/cross-plane_crank

 

[RiderGroups]

Here is another article that is specific to the ST & FZ07 crossplane crank.

http://www.sportrider.com/crossplane-what

 

[Steve_h80]

A cross plane on a twin isn't really possible, that needs to be a minimum of 4 cylinders or more - the word cross is the clue.
As noted above our 270 deg crank does offer some of the advantages in that the crank doesn't have the stop/start you get with a 180 or 360 crank (regardless of the number of cylinders).
A 120 crank on a triple ( or 6 cylinder or any multiple thereof) does the same thing in that the crank is driven all the time ie there is always something going up or down).
Dunno if I can tell any real difference on the road... but it sounds better.
Next subject - balancing the crank in any of the above ::26::

 

[La Knee]

They did a great job making it sound and work like a vtwin.

 

[BadNews]

They did a great job making it sound and work like a vtwin.

+1