Dual plug head for the road?

[Guest]

Is there any real world, i.e. street not track, advantage to running an 8 plug head on a GS1000ET?
Cheers

[49er]

Is there any real world, i.e. street not track, advantage to running an 8 plug head on a GS1000ET?
Cheers

Have you found one in Aotearoa? That sounds like a magical place to live!!

There is this post in the archives

http://www.thegsresources.com/_forum/showthread.php?t=85532&highlight=Twin+spark+plug+heads

Sounds like a lot of work for a road bike, with hassles just getting access to change some of the plugs. There were some photos that have now been removed. There's also a link to Old school Suzuki that may throw some light on its worth.

[KiwiGS]

Have you found one in Aotearoa? That sounds like a magical place to live!!

There is this post in the archives

http://www.thegsresources.com/_forum/showthread.php?t=85532&highlight=Twin+spark+plug+heads

Sounds like a lot of work for a road bike, with hassles just getting access to change some of the plugs. There were some photos that have now been removed. There's also a link to Old school Suzuki that may throw some light on its worth.

Gday mate,
There is one for sale on the Aotearoa TM at the moment.

I had 8 plug head on a Kwaka race bike, but it had so many other goodies that I was never quite sure of the gains from the 8 plug head alone.

At the very least the head would give a more effective fuel burn but is that worth hassle of the extra coils, wiring and mucking around.

Just thinking on a keyboard really.
Cheers

[trippivot]

no advantage period.

dual plugs help when the high compression piston dome is so big the ignition flame front is interrupted during compression event. the dual plugs ignite both sides of the combustion chamber.

[isleoman]

Kinda unrelated but I use to own two identical 1982 Nissan pick up trucks which had four cylinder engines with two spark plugs per cylinder. Use to love messing with the parts guys when I would ask for 8 spark plugs. Common response "Nissan makes an 8 cylinder pick up?

They do now with the Titan but they didn't back then. Those trucks use to fly. Phenominal power to weight. Loved to slide them around in the rain and snow.

[first timer]

another option to a dual plug head is to run a MSD mc-3 ingnition box. The box will throw a very hot spark every 35 degrees of crank rotation which will also help burn any unused fuel. My tuner recomended that to me over doing dual plugs on my 1000 yosh bike, but again i am going to be running 11.5:1 cr, ported head and hotter cams.

is that head for sale Smitty's old head? If so from what I have heard that head is really opened up and needs some big CC pistons to match it's flow.

[KiwiGS]

First timer: I dont think that the head is Smithie's.
He is selling some other stuff off though
GS 1000 Yoshimura Close Ratio Gearbox
GS 1000 High capacity Oil Pump
GS 1000 Racing Clutch, complete
GS 1000 APE high tensile studs and nuts
Cheers

[trippivot]

honda shadow 500 twin 2 plugs per cyl. vulcan 1500 twin same thing. but that is E.P.A. to avoid HC levels at idle--cam overlap duration along with wasted spark 2 pulse style. whizmo technical gadgets to appear more complex than they really are.

Kinda unrelated but I use to own two identical 1982 Nissan pick up trucks which had four cylinder engines with two spark plugs per cylinder. Use to love messing with the parts guys when I would ask for 8 spark plugs. Common response "Nissan makes an 8 cylinder pick up?

They do now with the Titan but they didn't back then. Those trucks use to fly. Phenominal power to weight. Loved to slide them around in the rain and snow.

[max parsons]

8 plug head

I have a GS1000 with an 8 plug head,it's in the 1980 gallery with the alloy tank.The guy who had it done wanted a smoother motor and it definitely is smooth.Getting the plugs out is easy but it's a real pain getting the plug caps on.The motor is modified so I don't know if there's any HP advantage.

[Jethro]

A good port, polish and flow test will provide a more efficient burn than a dual plug head.

[srsupertrap]

About the only bike that really benefited from a dual plug head on the street was the BMW R90 & R100's series and that was because BMW kept bumping the compression thru the 1970's to try to keep up with the Z-1's etc.

[sharpy]

Street cred is always a good exuse

[Big Jay]

"A good port, polish and flow test will provide a more efficient burn than a dual plug head."


Not if the chamber is full of piston dome.

[49er]

"A good port, polish and flow test will provide a more efficient burn than a dual plug head."


Not if the chamber is full of piston dome.

Tuners get greedy for CR and reduce the squish area. That is the major reason for a retarded burn off rate.