Resistor vs. non-resistor

[SanDiegoMike]

I just did a fluid change on my bike, and decided that it was probably time to change the plugs as well...seeing as how it hasn't been done since I've owned it (2 1/2 years). While I was at my local auto parts store getting motor oil and gear oil, I figured I would get plugs too. I gave the guy behind the counter the NGK and Champion numbers that I got from my manual, and he said that he didn't stock them because they were non-resistor type plugs.

The plugs that are in my bike now are Bosch Platinum +4 with R3 969 stamped on the porcelain. Like I mentioned, they have been in the bike since I've owned it, and it seems to run fine. I pulled them to look at how my mixture was burning, and all 4 look really good. So, now I have these questions:

Does the R3 indicate that these are resistor type plugs?
If so, does that mean that I should have non-resistor type caps?
How can I check to see what type of caps I do have? (I don't have a multimeter)
What happens if you run a non-resistor type plug with a non-resistor type cap? What if they are both resistor type?



I (like everyone else) want my bike to run as good as possible, so I look forward to the flood of info I am hoping this post will bring. Thanks!

[81xsproject]

I have been wanting to try out a set of the 4+. It is too bad you're taking them out and not putting them in to give a before and after review of performance.

[Hobbit]

Plugs

First- to answer your question, th eRdoes stand for resistor.

For example: WR7DTC

W = Diameter (?) W= 14 mm (?)
R = Resistor (Radio interference suppression, not vital(?))
7 = Heat Range (lower numbers = colder plugs)
D = Length (?)
T = Tri-cathode. If missing, single cathode
C = Copper Anode
Other values, Missing = Carbon, S = Silver, P = Platinum
0 = Final character, Special Electrode configuration

With in reason, a resistor cap and plug will not be to much for the ignition. The highest resistance in the circuit is the plug gap (at low voltage it's an open circuit). Once the spark has ionized the air/fuel mixture, the mixture ignites and becomes a conductor. The resistance in the plug, cap and wire is mainly there to reduce the number of coil oscillations, therefore reducing Radio Frequency Interferance.
I'd stick with the same type of plugs you removed.

[SanDiegoMike]

Thanks for the responses! Like I mentioned earlier, the +4's seem to work just fine, and I have a nice light tan color on all four insulators. I'll probably stick with them.

[Crazcnuk]

Basically, you use the resistor types if your bike (car) has a radio on it.

If you have a radio on your bike and you get a steady static pulse through the speakers you're getting interference from the ignition system.

Everything else about the plugs are the same, so a BP6ES is the same as a BPR6ES. (NGK)