No need to go off topic. The correct heat range, and plug for the application is a given. Between manufacturers, and "boutique" plugs, you'll find no power.
20 hp from a 250 isn't even 100 hp/liter.

 

Just a few thoughts. I have tried fancy plugs. MOST of them such as multiple electrodes will block the spark more than expose more of the spark to the combustion chamber.

If you have a spark plug with 2 neg electrodes or more, the spark will only go to one, it can't split in half.

The ones that make "hotter" spark do so with added resistance in the plug so it makes your coil work harder.

The engeneers figured out heat range and plug depth for us, so the standard plug is what we need.

I would switch plugs if some one can show me it makes more power or saves gas or makes my bike jump higher.

Most spark plug ads show the removing one that has been there WAY too long then claim performance gain by putting in the new gizmo plug when a OE replacement would have helped just as much.

Kind of like the exhaust folks showing us how much the new pipe adds to the bike in HP when jetting is changed too. The real fact is the jetting did more than the pipe.

Its cheap and fun to try all those fancy plugs. I did it a long time ago in other bikes. In the end, the plug called for was what worked best.

David

 

Yes, but you have to remember everything from "the factory" also is based on cost, if a cheap standard spark plug saves them 20 cents per unit over a platinum or iridium they will do it. Price drives alot of OE stuff. Nearly every aspect of performance can be looked at like this. Personally i have noticed a difference in my bike and in my cars/trucks when i installed better spark plugs.

 

EMS 0525 If you notice a difference great.

Our spark plug has a gap. The spark jumps the gap and ignites the air fuel mixture. If the plug is iridium or platinum, its not going to matter what the spark does. It still jumps the same size gap and makes the same size spark.

I have looked at spark voltage on the scope and can see no difference regardless of what the conductors of the spark plug are made of.

I just pulled a set of Iridium plugs out of an Equinox with 66,000 miles on it. Gap was worn about .010" although I did not put them in , so they could be worn more or less. Those plugs would have gone 100,000 miles in that car (EFI) with no problem. That is the only difference I see in the spark plugs made with exotic material. These plugs were original Equipment.

Surface gap, multi electrode and those silly ones that whistle all change or try to change the shape or orientation of the spark. This could have something to do with combustion, but not on our level.

Just opening up the gap will make a "hotter" or bigger spark, but it also makes the coil work harder to initiate and complete the spark so it could possibly overheat or spark could leak out at the coil or wire because its harder to jump the gap. This would cause reliability issues. Moisture would be a bigger problem too.

If we were working with 2 stroke, things would be different. If we had EFI things would be simpler yet.

David

 

Spark plugs and ignition systems are great places for aftermarket manufacturers to make big claims that make big money and especially with spark plugs. Now, there are also improvements that can be made with the right components. The only power benefit to be gained with spark plugs generally is better long term consistency with precious metals to retain spark quality longer.

Actual power gains can only come from increased spark intensity and spark duration. This can be achieved with better plug wires, caps, hotter coils, and devices that manipulate the spark intensity and/or duration. This is getting harder to do for the home mechanic with more modern computer controlled systems. Just changing to certain kinds of spark plug wires can actually interfere with the computer or other electronic elements in the system under some conditions.

One just can't throw the same blanket over all ignition system modifications. Some of these multi-electrode plugs with the right coil and such can actually help an older combustion chamber design's performance. Some older 2-valve heads need all the help they can get with promoting combustion and flame front efficiency. But even here there's only so much a spark plug can do. More modern engines with 4 or more valves and properly designed combustion chambers need spark boost tweaking less because of ideal fuel/air flow and spark location...and other factors.

Increasing the spark intensity and/or duration with something like an MSD aftermarket "box" coupled with a stronger coil system, "can" improve performance under the best circumstances and at least provide consistent performance over a longer period. Generally high compression ratios and high rpm are the challenges for an ignition system when everything else meets some minimum requirement. Our KLX's may have a 10,000 rpm redline, but with one coil firing one cylinder in a cylinder head with ideal valve and spark plug placement, it's probably not a challenging environment for the spark plug.

 

Exactly the factory says "What is the cheapest spark plug we can get that meets this guideline for what WE want the bike to do."

 

OK here's another "hot item" along the same lines for discussion:

Booster Motorsports

 

Man, I don't know. That's one of those devices that has that appearance of high performance wallet sucking rather than engine high performance. The problem with a device like this is that if it can produce one tiny miniscule amount of benefit, excessive claims of all kinds often get made. To be truthful, I don't know enough about this item to be qualified to poo-poo it, but I see nothing that is adding true spark energy or true spark duration. Sounds like they're manipulating the spark with some kind of resistance trick and just adding a better quality plug wire, cap/boot. I'm su****ious when I don't see a powered device like an MSD box or such that actually increases spark energy or duration in some manner.

 

I thought you went black because all the cool kids are doing it!

 

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

I don't know about your KLX, but mine came a NGK plug.