Firing order-Remixed comes to Bikes?

netchef · 3rd December 2007, 17:26

I rode a Yamaha 1400 V-4 Royal Star recently only to discover (to my dismay) that the firing sequence seemed to be designed to mimic the sound of a Harley. Phew. Remixed comes to Bikes??

To my mind, the ideal solution would have been evenly spaced firing intervals around 360 deg, which meant a 4-cyl job would yield one power pulse every 90 degrees to get the most out of those 4 pots in terms of smoothness among other things...correct me if I'm wrong.

Another way of looking at it- why have 4 pots if you're going to have 2 of them fire together?

Also read somewhere of racing boffs at HRc and Kwackers deciding between 'screamer' and 'growler' engines, based presumably around a similar approach t timing-management.

What say?

Sankar · 3rd December 2007, 21:45

It has an effect on torque delivery... growler engines have more torque at hand, lots of it, come in large pulses. Screamer has a smoother torque delivery.

netchef · 4th December 2007, 14:05

Ah. Does that mean that auto engineering has come full circle? That the push for high-revving machines- with a naturally narrow power-band- is being revised towards slower-revving, torquier engines?

It somehow sticks in my craw that racing machines could run the lazy-dog engines of their cruiser counterparts...just can't imagine it.

Sankar · 4th December 2007, 14:32

Hmm... not exactly. Big bang engine sused in racing are not exactly lazy slow cruiser engines.

By having two cylinders firing at the same time doesnt mean the engine has to be slow revving.

men_in_jean · 4th December 2007, 16:19

I am wondering why i do not understand anything in this thread!! technical stuff..

netchef · 4th December 2007, 16:43

Sankar- you got a point there.

Men_in_jean: :-)
I trip on quasi tech stuff as a facet to biking. But it needn't be everyone's cup of tea.

Spitfire · 4th December 2007, 18:53

Quote:

Originally Posted by netchef

I rode a Yamaha 1400 V-4 Royal Star recently only to discover (to my dismay) that the firing sequence seemed to be designed to mimic the sound of a Harley. Phew. Remixed comes to Bikes??

Which other bike in the Yamaha range uses this engine? And whats the firing sequence in that?

netchef · 5th December 2007, 10:52

No clue, Spitfire. All I know is the Royal Star is a cruiser/street basher type of m/c, and she's naked. If I recall right, she was a shaftie.

doomsday · 6th December 2007, 09:44

I think all of us needn't throw in the towel yet for high revving engines. These types of firing sequences will be reserved for relaxed cruiser/street motorcycles wherein a large steady power/torque curve is desired rather than a peaky surge at very high revs. It all boils down to usabililty and customer preferences.I don't think track tools will be incorporating these kind of firing sequences any time soon.

Spitfire · 6th December 2007, 12:34

Doomsday is right firing sequence is altered as per the purpose of the bike.

Sankar · 6th December 2007, 13:18

Most of the 990cc motogp bikes were running on the big bang configuration, except the kawasaki. These bikes were putting out a lot of power and the big bang motors helped a lot in preserving the tires and the thus the drive out of corners.

And most of the current 800cc motogp bikes have reverted back to the screamer configuration. Again except the Kawasaki.. kawasaki seems to do it opposite to what everbody else is doing.

The 2005 yamaha wsb bike also ran a big bang configuration.. but instead of firing two cylinders together it fired 1 cylinder first, then 2 cylinders together, and then the 4th cylinder.

Big bang was introduced during the mick doohan era by the honda to tame those fearsome 500cc two stroke motors. But then some others switched to the big bang config and the lap times were becoming stagnant and mighty mick went for a screamer config

on the 500cc v4 two strokes and he was winning and lap times improved

Big bang is easy on the tires and on the riders.

netchef · 7th December 2007, 10:44

Thanks for enlightening, chaps.
Talking of screamers, remember the Honda 125 x 5 and 250 x 6 cyl racers of the 60s? The bloody 125s wld rev to 22,000 RPM, and a pit joke went that they wld begin to misfire if so much as a cloud passed over the circuit. (I heard a Suzy GSXR600 sports-prepped m/c recently in the hands of a V Capable rider, and at 16K RPM, she was the most glorious thing I'd heard short of a Formula 1 car, so I can well imagine what the 60s Honda racers must have sounded like.
I remember Mick Doohan. Some of his vintage were awesome riders. Older gen too with names like Geoff Duke, M Hailwood etc. ..real men. Bikes with heaps of horses, but hardly much else in terms of suspension or brakes. They were tough. Kenny Roberts Sr who was not really vintage once said he wasn't paid enough to ride the 750 Yam 2 stroke he raced (no brakes to talk of).

3rd December 2007, 17:26	#1
netchef BHPian Join Date: Oct 2007 Location: Bangalore Posts: 952 Thanked: 60 Times View My Garage	Firing order-Remixed comes to Bikes? I rode a Yamaha 1400 V-4 Royal Star recently only to discover (to my dismay) that the firing sequence seemed to be designed to mimic the sound of a Harley. Phew. Remixed comes to Bikes?? To my mind, the ideal solution would have been evenly spaced firing intervals around 360 deg, which meant a 4-cyl job would yield one power pulse every 90 degrees to get the most out of those 4 pots in terms of smoothness among other things...correct me if I'm wrong. Another way of looking at it- why have 4 pots if you're going to have 2 of them fire together? Also read somewhere of racing boffs at HRc and Kwackers deciding between 'screamer' and 'growler' engines, based presumably around a similar approach t timing-management. What say?
	() Thanks

3rd December 2007, 21:45	#2
Sankar Senior - BHPian Join Date: May 2005 Location: Location Posts: 5,780 Thanked: 9,253 Times	It has an effect on torque delivery... growler engines have more torque at hand, lots of it, come in large pulses. Screamer has a smoother torque delivery.
	() Thanks

4th December 2007, 14:05	#3
netchef BHPian Join Date: Oct 2007 Location: Bangalore Posts: 952 Thanked: 60 Times View My Garage	Ah. Does that mean that auto engineering has come full circle? That the push for high-revving machines- with a naturally narrow power-band- is being revised towards slower-revving, torquier engines? It somehow sticks in my craw that racing machines could run the lazy-dog engines of their cruiser counterparts...just can't imagine it.
	() Thanks

4th December 2007, 14:32	#4
Sankar Senior - BHPian Join Date: May 2005 Location: Location Posts: 5,780 Thanked: 9,253 Times	Hmm... not exactly. Big bang engine sused in racing are not exactly lazy slow cruiser engines. By having two cylinders firing at the same time doesnt mean the engine has to be slow revving.
	() Thanks

4th December 2007, 16:19	#5
men_in_jean BHPian Join Date: Dec 2006 Location: Chennai Posts: 68 Thanked: 0 Times	I am wondering why i do not understand anything in this thread!! technical stuff..
	() Thanks

4th December 2007, 16:43	#6
netchef BHPian Join Date: Oct 2007 Location: Bangalore Posts: 952 Thanked: 60 Times View My Garage	Sankar- you got a point there. Men_in_jean: :-) I trip on quasi tech stuff as a facet to biking. But it needn't be everyone's cup of tea.
	() Thanks

5th December 2007, 10:52	#8
netchef BHPian Join Date: Oct 2007 Location: Bangalore Posts: 952 Thanked: 60 Times View My Garage	No clue, Spitfire. All I know is the Royal Star is a cruiser/street basher type of m/c, and she's naked. If I recall right, she was a shaftie.
	() Thanks

6th December 2007, 09:44	#9
doomsday BHPian Join Date: Mar 2006 Location: Bangalore Posts: 424 Thanked: 59 Times	I think all of us needn't throw in the towel yet for high revving engines. These types of firing sequences will be reserved for relaxed cruiser/street motorcycles wherein a large steady power/torque curve is desired rather than a peaky surge at very high revs. It all boils down to usabililty and customer preferences.I don't think track tools will be incorporating these kind of firing sequences any time soon. Last edited by doomsday : 6th December 2007 at 09:50.
	() Thanks

6th December 2007, 12:34	#10
Spitfire BANNED Join Date: Jul 2006 Location: Panaji - Goa/Bangalore - Karnataka Posts: 3,313 Thanked: 778 Times	Doomsday is right firing sequence is altered as per the purpose of the bike.
	() Thanks

6th December 2007, 13:18	#11
Sankar Senior - BHPian Join Date: May 2005 Location: Location Posts: 5,780 Thanked: 9,253 Times	Most of the 990cc motogp bikes were running on the big bang configuration, except the kawasaki. These bikes were putting out a lot of power and the big bang motors helped a lot in preserving the tires and the thus the drive out of corners. And most of the current 800cc motogp bikes have reverted back to the screamer configuration. Again except the Kawasaki.. kawasaki seems to do it opposite to what everbody else is doing. The 2005 yamaha wsb bike also ran a big bang configuration.. but instead of firing two cylinders together it fired 1 cylinder first, then 2 cylinders together, and then the 4th cylinder. Big bang was introduced during the mick doohan era by the honda to tame those fearsome 500cc two stroke motors. But then some others switched to the big bang config and the lap times were becoming stagnant and mighty mick went for a screamer config on the 500cc v4 two strokes and he was winning and lap times improved Big bang is easy on the tires and on the riders.
	() Thanks

7th December 2007, 10:44	#12
netchef BHPian Join Date: Oct 2007 Location: Bangalore Posts: 952 Thanked: 60 Times View My Garage	Thanks for enlightening, chaps. Talking of screamers, remember the Honda 125 x 5 and 250 x 6 cyl racers of the 60s? The bloody 125s wld rev to 22,000 RPM, and a pit joke went that they wld begin to misfire if so much as a cloud passed over the circuit. (I heard a Suzy GSXR600 sports-prepped m/c recently in the hands of a V Capable rider, and at 16K RPM, she was the most glorious thing I'd heard short of a Formula 1 car, so I can well imagine what the 60s Honda racers must have sounded like. I remember Mick Doohan. Some of his vintage were awesome riders. Older gen too with names like Geoff Duke, M Hailwood etc. ..real men. Bikes with heaps of horses, but hardly much else in terms of suspension or brakes. They were tough. Kenny Roberts Sr who was not really vintage once said he wasn't paid enough to ride the 750 Yam 2 stroke he raced (no brakes to talk of).
	() Thanks