It is now a thing of the past to see performance motorcycles coming with only a single spark plug. The reason that we are being told is that it is to improve performance of the bikes, but is it really the truth? Or is using multiple spark plugs in a single cylinder only a sham. The answer to this question is not a simple one because there is a lot that goes into every decision being made into the research and development of any bike, be it a 100cc commuter or a 1000cc superbike. So nobody just simply wakes up one day and says that give the bike 3 spark plugs. But then again, this is a very debatable topic. So we are going to check out if twin spark plugs in motorcycle engines really give them an advantage or just a marketing gimmick.First of all let’s see the way spark plugs perform. In an internal combustion engine of the motorcycle, the air and fuel mixture enters inside, the spark plugs ignite the mixture and that’s that. Now in the same case you put in 2 spark plugs and the result is not really going to change much, unless you are having issues with incomplete combustion. This happens when the fuel is not getting completely burnt and hence it leaving out smoke and lots of pollutants in the process.
READ ALSO: What Is The Use Of Twin Spark Plugs (Dtsi) In Motorcycle Engines?
What one has to realize is that not only is this harmful to the environment, but it also causes issues in terms of performance loss since the unburnt fuel means less power generation. Now for the problem for this happening could be many. Like a short stroke engine which is not really providing enough time between cycles for the mixture to combust fully. Else maybe the stroke is too long such that the flame is not reaching certain parts of the chamber leaving unburnt fuel in the mix.
So how can this problem be sorted out? The solution by providing another ignition source in the areas where the fuel is being left unburnt. This is how the Bajaj twin-spark technology came into being. With the inclusion of technology they allowed more fuel to be burnt in less time and hence resulted in increased performance using two spark plugs.Then again the question pops to mind, for bikes with high engine capacity, one can understand, but even for bikes with lower cc engines? Let’s take the example of the KTM Duke 200 and the Bajaj Pulsar 200NS. The Duke uses single spark plug setup while the 200NS uses 3 spark plugs. And even with this, the Duke produces more power and torque from the same capacity engine while the NS produces less. Ever wondered why?
The answer to this question is very simple; Fuel injection. Now how fuel injection works has already been explained before. You can check that out right here. But to put it in terms here, the injected fuel in the molecular level easily ignites as the efficiency of it is better since it is already being stressed up to ignite. For the same thing, the 200NS with a carburetor needs 3 spark plugs to get all that fuel burnt up efficiently.
So at the end of it for a conclusion if you ask me if it is a boon or a bane, I will definitely sum it up this way. If you take a bike with higher capacity and put in multiple spark plugs because it needs them, then yes, it is a boon. But if you take a commuter and put twin sparks on it and say that it does provide an advantage, I would say that it is rubbish. Always remember that higher the number of holes in the combustion chamber, the more stressed up it will be and the more likely are the chances to falter. So it is always better to keep things simple.
By: Pratik Patole