2003 K1200RS Spark Plugs

[jrlunsford]

My K12RS has 20,161 mile on it and it seems not to be running as good as it first did when I purchased it. I always keep it on the center stand when parked and when I crank it up it smokes like a freight train, white smoke and when I riv it up it just shoots a white smoke stream out the exaust. Then I take it out for a 4 or 5 miles run and when I get back it doesn't smoke at all. It's been sitting for about 3 weeks though. I was wondering why the bike smokes when it's been sitting up for a few days ? Also it just doesn't seem to have the power that it did have and I also was wondering could it need new plugs and if so what kind should I put in it?

[Laney]

I don't know about on the centerstand, but 3 weeks on the side stand can leave a KRS with some oil in the cylinders that needs to burn off. If it does it when parked for a short time, or every time it's parked, I'd look into it.

 

I thought plugs got changed at 12K - if not 12K, then definitely 24K. I don't know about alternates, I just went to the dealer for mine since it's rarely more than a once a year expense for mine.

 

Check on K-bikes.com, maybe you can find an alternate plug listed over there.

[Bruce C]

For an alternate spark plug try: NGK DCPR7E gap .032".

The Bosch number is XR7LDC gap .030"-.034".

Bruce C

[Bobmws]

White smoke is usually indicative of water. Check your coolant level. If the bike sat for 3 weeks here in FL, it could just be moisture that has condensed in the pipe. How far into your 5 mile ride did the plume last?

As for plugs, I would stay with the factory recommended plug while you're still in warranty. BMW has been known to reject a claim due to the wrong plug being in the motor.

[Fasterpill]

All this is good to know as my bike suddenly developed a miss at 32K. Guess I better order some of those plugs.

 

Most cold engines put out white smoke in cooler weather at start up. Something partly to do with hot steam from fuel combustion hitting cold cylinder walls & exhaust parts that act as condensers. Should only last a minute or two. Unless you're Laney...

[BrentBoshart]

I'd stay with stock plugs. Here is a good internet source at $4.95 each http://www.euromotoelectrics.com/

Good prices on O2 sensors too.

[Dennis Andress]

All this is good to know as my bike suddenly developed a miss at 32K.

 

Hi Phil,

 

A couple of weeks ago my bike developed a miss and began running rich after I'd changed the plugs and air filter. I found that replacing the #4 plug wire cleared up the misfire and replacing all four wires greatly reduced vibration. The #4 wire meassured 6.9K Ohms and the others between 6.2K and 6.4K. I swapped the wires off my K100 which are only a year old. All of them meassured under 5.9K Ohms

[Fasterpill]

I was wondering about the wires. I'll start with plugs cuz they're cheaper and overdue and we'll take it from there. As bullet proof as these bikes can be, they're pretty fussy with that motronic.

[Dennis Andress]

I was wondering about the wires. I'll start with plugs cuz they're cheaper and overdue and we'll take it from there. As bullet proof as these bikes can be, they're pretty fussy with that motronic.

 

My old K100RS goes away this weekend. Part of me wishes I could fix it but now is not the time. It's going to an old friend in Tucson who worked at Iron Horse for many years. He'll be able to fix it right and really appreciate it when it's done. I guess I owe him a set of wires.

 

Dennis

[Laney]

Should only last a minute or two. Unless you're Laney...

 

Yeah, if you're me, and ride your RS like a girl, you may find the white smoke won't go away.

 

Bit I'm reformed now - I don't ride like a girl any longer.

 

Now, I Wrench Like a Girl.

 

Oh, wait a minute...

[RFW]

The #4 wire meassured 6.9K Ohms and the others between 6.2K and 6.4K. I swapped the wires off my K100 which are only a year old. All of them meassured under 5.9K Ohms

Plug wire resistance has nothing to do with the how well the plug sparks.

 

The purpose of resistance wire is that it snubs out high frequency parasitic oscillation caused by the parasitic inductance and capacitance of the wire. The purpose of this is only to eliminate radio interference.

 

The resistance of the wire is poorly controlled even when new, and also varies directly with its length. I'd venture to say that a resitivity tolerance of something like +/-20% on new cables (on a resistance per unit length basis) would be all that you can expect.

 

Your misfire was not caused by a non-optimal resistance, but undoubtably by an insulation breakdown in the cable. resulting in the spark intermittantly shorting to ground.

 

The old way to tell if there was a problem was to start the vehicle in the dark and look at the wires. With bad wires, one could often see a lightshow of small sparks along the wire.

 

Bob.

[Dennis Andress]

What the heck, why not.....

 

These are not carbon wires. They use real wire and a 5K Ohm resistor in the cap. Considering this I would question any large variance in measured resistance Undoubtedly, there was some degradation of the insulation but I found no reason to believe enough to cause arching.

 

My electronics, semi-conductor, and avionics knowledge and experience don't get used much these days but I recall that the basic concept of a spark plug is that the secondary of the coil will build up voltage until it is sufficient to jump the gap of the spark plug. Adding a resistance, or changing one already present, to the inductance of the coil secondary winding would change the phase between voltage and current and the time needed for spark to be produced.

 

Or, rather, I changed the #4 plug, which had the highest resistance, first and my problem went away. I changed the other three because I had the wires in my hand and my bike ran better than ever.

 

Excuse me, I hear the diner bell.

 

Dennis