Spark Plugs

[RoostDaddy]

just wondering what plug everyone is running in their k5.
I know some electrical systems on other bikes are sensitive and resistor type plugs are recommended, but never ran into this with the k5.
Also, is there any benefit to running the projected type plug, I've heard people claim they are easier firing?

[monster malibu]

I'm running NGK B8EG's.

[Mick]

I've used nothing but the cheap-O B8ES in my KX.  The only covet is to gap the plug on the tight side so it fires easy.
But if you want to know about projected noses I'll tell you my experience with them...they're awsome!  It's not a horsepower thing nor does it have anything to do with performance persae, but they sure do age well.  A typical plug in either of my 500s starts great and runs real clean off the bottom for several rides, and then begins to get fussy with starting and maybe flaming out at idle speeds after a dozen or so rides.  When it becomes habit that the motor backfires once or twice before it starts I change the plug and the cycle starts all over again.  I've used ONE projected nose tip plug in my life.  It's in my CR right now and has 24 rides on it plus or minus and starts just as effortlessly and chugs everybit as good as day numero uno.  More still is that while testing a new ignition at one time I was running stupid rich jetting that I'm sure would have put the kill shot on a B8ES or IX plug.  The BP8ES runs very clean.  Technically speaking it burns off carbon residue at low rpm that may otherwise foul a typical plug.  And yet at higher rpm is even capable of running cooler so as to mitigate pre det and plug melting.  Projected nose tip plugs are going to be the only kind I use from now on.

[KXcam22]

I ran the cheapo BPR8ES (projected nose) plug for the 14 years I had my K5.  I order them from NAPA or Lorco.  Each one lasted a season and never fouled ever.  I heard that the EIX plugs make more power but never tried them in the K5. Cam.

[Hillclimb#42]

Getting BR8ES for less than $2/plug from O'reily's Auto Parts. Am I missing out on power? They last a long time and the center electrode is not small like on some. The little pencil-lead size electrodes seem like they would oil or carbon foul faster. I learned that fast/wise people are paying attention to which direction the gap is facing in the cylinder. Open-side towards intake, I think, but there's always an exception to theory.

[monster malibu]

What's the difference between the BPR8ES and the BP8ES?

[KXcam22]

The "P" stands for projected nose.  On most 2 strokes the comustion chamber has enough of a pocket to give lots of clearance to run the "P" type.  Hillclimber, the fine wire electodes like on the EV, EG, or EIX plugs run at a much, much higher temperature which is why they don't foul -they burn themselves clean.  I found that my bike started noticeably better with the "P" plug, routinely 1 kick hot or cold.  You should be able to get those at O'reily's also for $2.  I never bothered with plug indexing on a 2 stroke since the intake charge mostly comes from the sides.  Maybe I should. Cam.

[93KX5Rider]

I run my kx with a NGK BR8EIX... I had BR7ES in it last winter when I put it away and I took it out and put in this new plug and it is running a lot better then it was before I put it away for the winter. I would recommend this plug.

[RoostDaddy]

thanks for the replys, this was what I was looking for.  As i said about the Projected plugs, there must be something that helps with firing.  As for plug indexing, I've done it for years.  Does it help, I couldn't tell you but It sure does make people look when you put a Sharpie mark on you plug and snug it up ever so carefully!  Maybe its just some superstitious thing if nothing else.

[Sofus]

I just got a new BPR8ES after reading this thread.

Oh my god, what a difference that made! The bikes starts much better, and pulls wheelies in 2 and 3 as well.

Now I just have a new problem, all those wheelies made my forks blow a gasket My "new" bike is in such a bad shape, I really have to do a full teardown/rebuild.

[ToomanyKaws]

I have run the BR8ES and the BR8EG in my KX500.   Seems to run the same on both plugs.   Always have a spare 8 plug period in my camelback pack though.   The one time I didn't and the only time my KX250 ever fouled a plug.   The 500 been easy on plugs and have yet to foul one.  Like having a fresh one in there though just to avoid the hassle of swapping out in the desert.    KDX200 been on the same plug for three years.   Afraid to touch it.  Starts on the 2nd kick cold and 1st hot, all the time.   

[stock500]

I just changed to the BPR8ES and didn't notice any difference at all in performance, but it was sure time for a new plug. 

[gwcrim]

I run a reg'lar old B8ES.  They actually last for years if you jet properly.

[Mick]

I just got a new BPR8ES after reading this thread.

Oh my god, what a difference that made! The bikes starts much better, and pulls wheelies in 2 and 3 as well.

Your old plug must have been worn pretty far beyond the limit to yield such a noticable gain...no spark plug IMO really provides any performance benefit over the next.  I don't buy that iridium hype, I've tried them...no different than a B8ES.

But what does matter is plug gap!  Especially on our 500s.  Do understand that as a plug wears the electrode gap increases.  As the gap increases and the electrode becomes more and more contaminated with carbon the ability for that spark to bridge the gap becomes increasingly more difficult.  Now no spark plug I've EVER measured out of the box had the correct gap for my bike. They always have too much.  And when going from a well carboned plug with a huge gap to a nice fresh plug with the correct gap then yes, there should be a seat of the pants boost in performance.
I've just been exceedingly pleased with the projected nose plugs because they seem to perform "like new, fresh out of the box" for a very long time.

[bob larry]

I just got a new BPR8ES after reading this thread.

Oh my god, what a difference that made! The bikes starts much better, and pulls wheelies in 2 and 3 as well.

Your old plug must have been worn pretty far beyond the limit to yield such a noticable gain...no spark plug IMO really provides any performance benefit over the next.  I don't buy that iridium hype, I've tried them...no different than a B8ES.

But what does matter is plug gap!  Especially on our 500s.  Do understand that as a plug wears the electrode gap increases.  As the gap increases and the electrode becomes more and more contaminated with carbon the ability for that spark to bridge the gap becomes increasingly more difficult.  Now no spark plug I've EVER measured out of the box had the correct gap for my bike. They always have too much.  And when going from a well carboned plug with a huge gap to a nice fresh plug with the correct gap then yes, there should be a seat of the pants boost in performance.
I've just been exceedingly pleased with the projected nose plugs because they seem to perform "like new, fresh out of the box" for a very long time.

What do you gap your plugs at??