Topic: Think about this...

[lucky]

A honda CB750 has a firing order of 1-2-4-3 but get this plugs 1 &4 fire at the same time even though one of the cylinders is NOT on the compression stroke.
Also cylinders 2&3  fire at the same time even though one cylinder is not on the compression stroke.
Honda V4's are that way too. Two coils each firing two plugs at the same time? Not sure because it is controlled by a $375.00 black box.

Most engines like cars have a distributor and each cylinder fires one at a time like 1-4-3-2 or 1-3-4-2.

So on the honda engine one cylinder is firing when that cylinder is NOT on the compression stroke. both lobes are up and it is on overlap? Right.

Weird. What are the ramafications?

[MCRider]

Its called a "wasted spark". No ramifications at all.

[lucky]

Its called a "wasted spark". No ramifications at all.

I like simple answers but wouldn't that extra spark get rid of any unburnt gases?

[MCRider]

Its called a "wasted spark". No ramifications at all.

I like simple answers but wouldn't that extra spark get rid of any unburnt gases?

Probably not IMO. That would require compression to get them to burn more fully and as we know, the wasted spark stroke has no compression. But, that's just my opinion, no facts to back it up.

[CycleRanger]

http://en.wikipedia.org/wiki/Wasted_spark

http://www.gill.co.uk/products/digital_ignition/introduction/8_wast_spark.asp   <====Pix! 

[phil71]

a sequential spark system would literally double the life of your spark plugs. Woo hoo?

[BeSeeingYou]

If we could only harness the energy of all the wasted sparks.....
 
Give my creation... Life

[dave500]

you havent toyed with later than 80s cars for a while then,even a four stroke lawn mower timed of the crank has a wasted spark,plenty of new non distributor equipped cars also run a wasted spark,lift the hood on most little four cylinder cars and youll see two coils with two plug leads per coil,even a v6 will have three coils.
i always carry spare sparks under seat incase i waste too many,,this box has just enough to get home with.

[xsmooth69x]

you havent toyed with later than 80s cars for a while then,even a four stroke lawn mower timed of the crank has a wasted spark,plenty of new non distributor equipped cars also run a wasted spark,lift the hood on most little four cylinder cars and youll see two coils with two plug leads per coil,even a v6 will have three coils.
i always carry spare sparks under seat incase i waste too many,,this box has just enough to get home with.

lawl

[madmtnmotors]

Where the heck did you find those?! I've been looking everywhere for them!

[lucky]

Thanks for all the input people!!
I learn new stuff everyday.

[KingCustomCycles.com]

As sparks become more scarce, we will see less and less of this design.

[my78k]

You guys really are a sarcastic bunch!!

Dennis

[m in sc]

it is used extensively in more modern 2-stroke designs. since most have the spark tiggered at the flywheel there are few benefits. 1: both cyls are timed exaclty 180 from each other so therefore its virtually impossible to get the cyls fighting eachother as opposed to 2 sets of points/pickups slightly out. most 2t cranks are pressed units so this is huge. 2: it does burn unburnt fuel and help w/scavenging in the 2t applications. 3: as mentioned, simplicity of components. going froma 2 points system to awasted spark in most twins with no other changes immediately improves performance.  the only possible downside to this is the amount of time the coil can saturate with a charge, but this usually isnt a problem unless the revs get just stupidly high(over 15K) . just my .02

[70CB750]

Those wasted sparks actually cause global warming, earthquake in Virginia and El Nino, somebody should do something about it.

[CycleRanger]

As sparks become more scarce, we will see less and less of this design.

We need to develop our own domestic sources of sparks so we don't have to rely on other countries for our sparks!
Spark here, spark now!

[Duke McDukiedook]

Yes!! Vote for no more wasted sparkles!! What?!?! 

[OldSchool_IsCool]

You can use this neat feature if you want.  Take your cam shaft, cut it in half at the sprocket, weld it back together with the left side rotated 180 degrees, then 1&4 fire together as do 2&3.  Huge low end torque but not much top end. Ideal for a hill climber

Search for Big Bang Cam if you're curious.

[BobbyR]

Wasted spark is not new the Harleys always had it. All my cars have wasted spark also. You are correct it also helps eliminate some of the unburned fuel.

[Gordon]

You can use this neat feature if you want.  Take your cam shaft, cut it in half at the sprocket, weld it back together with the left side rotated 180 degrees, then 1&4 fire together as do 2&3.  Huge low end torque but not much top end. Ideal for a hill climber

Search for Big Bang Cam if you're curious.

But do you rotate half the cam forward or backwards?  What if you rotated each half 90 degrees in opposite directions?  Do you do the opposite if you're in the Southern hemisphere?

[toytuff]

Thanks for all the input people!!
I learn new stuff everyday.

Me too!

tt

[xsmooth69x]

As sparks become more scarce, we will see less and less of this design.

We need to develop our own domestic sources of sparks so we don't have to rely on other countries for our sparks!
Spark here, spark now!

i harness my spark from the sun! muahahahaha

[Retro Rocket]

i harness my spark from the sun! muahahahaha

That would make you a "real bright spark" then wouldn't it.....

[Grnrngr]

I saw suma them sparks tha other day, sittin around on the steps smokin that reefah..