09' crank and firing order?

rodantking · Mar 22, 2009

I sure this has been discussed, but I cant find what I'm looking for. I understand the concept behind the cross plane crank shaft, but on yamaha's website they list #2 and #4 to be at 180 degrees. The pics that Diel post up, all the pistons are progressive moving up in location. this to me mean 90,180,270,360.
The bigger head scratcher is the big bang. Yamaha does say any thing about it, but mags do and it does sound like it has one. I don't believe it does though. If 1 and 3 fire and 2 and 4 fire and the second revolution of the crank, it's still going to sound different because 1 and 3 are halve the distance apart from each other (as they would be normally). 4 and 1 are the only standard (same as a normal crank) firing interval.

I am I seeing this right?

stupac · Mar 22, 2009

the 09 is more of a long bang engine. If you search there have been multiple posts showing the degree gap between the piston firings.

kynetguy · Mar 22, 2009

ACtually most big bangs fire 1-4 and 2-3, I am pretty certain. be that as it may. . .

No, this is not a big bang motor AT ALL. It has been incorrectly called that by many sources and it DRIVE ME FOOOKING BATTY.

Long bang? Well that is about as good of a name as any I suppose. But the goal from yamaha was to even out the torque pulses from ignition. (combustion torque) This combined with inertial torque created by the rotating mass, makes for a smoother torque delivery, and thus, better traction. Back are the days of low end torque.

Those of you good at ready dyn charts for more than peak numbers, should compare and 09 to a previous model. Just admire the curves. The torque curve on the 09 is a beautiful thing. :fact.

Bogie · Mar 22, 2009

kynetguy said:
Those of you good at ready dyn charts for more than peak numbers, should compare and 09 to a previous model. Just admire the curves. The torque curve on the 09 is a beautiful thing. :fact.

I don't need a chart.....my "seat of the pants" dyno tells the power delivery of this bike is sweet!! :rock :flex:

diel11 · Mar 22, 2009

Firing order is 1,3,2,4. So if you look at the pics I posted, they are not progressive. You will see #1 piston, then 3 after it, then 2 then 4.

HKr1 · Mar 22, 2009

Seen this pic while I was poking around.

kynetguy · Mar 22, 2009

That is an interesting representation of firing orders and crank configs. Not sure what exactly they are trying to show though because that only represents 360 degrees of crank rotation, so :sing:

09' crank and firing order?

Attachments

Top Contributors this Month

Recommended Communities