Britbike forum Forums British motorcycles in general British motorcycles in general Champion N3C specs

I have found in the loft some old boxes empty of Champion sparks plugs N3 OEM number 801.
And now I can find Champion N3C in Spain, but with the OEM number 086.
Are they the same item that the olds N3C, in all their range?

Back in the early '70s, the available spark plugs were N3, and those were what was specified in my Chilton BSA Repair and Tune-Up Guide.

After a while, N3s were no longer available in the auto supply stores and had been more or less replaced by N3C. So I have to believe that they are the same, or at least close enough to be compatible. I've run Champion N3Cs in my A65s ever since.

N3C is so designated for the copper center conductor. It's the same thing only better?
Still, it's the only plug I use.

Is it hotter or colder than the NGK B8ES?

As tested at MIRA in UK by Triumph Corp. N3 is colder than a B8ES.

That's the problem with the so-called "interchange" list with plugs.

If possible, it's better to go with original BSA, Triumph, or other requirements so you know what you are buying.

An N3 will be an N3 regardless of any other letters
Plugs are supplied pre gapped and each gap will have a different stock number

All plugs overlap other plugs
Champions have a much broader temperature range than NGK's
So a 3 in Champion will cover the range of 8 through to 6 in NGK's
Champions are a very old plug & their numbers reflect the engines of the 30's to 50's
NGK are a much latter brand and make plugs for far more modern engines where operating temperatures were much closer defined
FWIW
B8's will work fine if you do long rides as they will take a lot longer to get to operating temperature
B7's are better for city riding or shorter trips
B6 if you think 20 miles is a long ride
BP's are far less likley to foul but you need to check the piston will not foul on the electrode .
Most BSA engines under 11:1 will be fine with projected electrode plugs
Don't know about lesser makes as I only ride BSA's

And remember the plugs BSA recommended were for burning 1970's petrol
This liquid has not been availible for 30 years so you will need to do some expirementing to find the right plug for your bile, running on your fuels being ridden the way you ride it
The standard plug for the M20 would be a B8HS
I can only run B8's if I am doing a run of 100 km or more and if I stop within the first 20 km the plug will foul
I usually run BP7 in summer & BP6 in winter

Easiest way to check the range is to run the bike till the engine is at full temperature then find a long downhill road and go down on overrun using engine breaking
Do a chop at the bottom
If the plug has fouled you need a hotter plug
GO up the same hill in the highest gear you can pull
If you get detonation then the plug is too hot .
This of course is dependent upon your engine being timed correctly & carb properly adjusted .

Way back in the 60s and 70s I always used Champion N-2s and N3s, and if I remember correctly N-2Gs and N3Gs in my race bikes, but I switched over to NGKs decades ago. Anyway, having not much to do motorcycle-wise while I wait for the snow and ice to melt, after reading this thread and others talking about Champions, yesterday I went off in search of some good old N3Cs to put into my Brit bikes this year, when I can ride again. I found 4 at an O’Reilly’s auto parts near me, and another 4 at another branch across town. Dusty packages, for sure, and perhaps the last 8 in the state, but it’ll be nice to know my Britbikes will have proper vintage friendly Champion plugs in them again. This may be really good evidence I’m sick of winter and eager to ride again, LOL.

Hi BSA WM20; for the T140E B8; B7; BP8; BP7 foul plugs. Do you say B6 for a short ride. B6 is what the charts of NGK says is the supposed interchange with the N5 (the ones used with the T140E)
I have been using the bike only on the road and for 60 to 250km commutes with B6ES or BP6ES (and D8HA for the smaller plugs with the dual plug head) after tested all the others.

I found a bunch of N3Cs at a used tool closeout store in Nashville for $1 each and bought all they had. I guess I'm set for plugs.
I used to run B7EX in my A65, but it was usually used around town. I never liked that bike on the interstate and didn't trust it to go too far from home. It pinged at 3-4000rpm with any plugs I ever put in it anyway.

Yes try a B6
Plug heat ranges do not directly cross to a single specific number
Plugs just hae to stay hot enough not to foul but cold enough not to detonate the incoming charge
If you are looking for 11/10th performance then they become very critical
If you are road riding not so much of a problem

I have had plugs foul twice on long rides because I forgot to change them , both on the over run
One happened about 1.5 hours into the last leg of a 400km ride
the other happened 2 hours into the same ride going home a different way

What people never seem to understand is the original plug recommendations were for running on leaded super petrol
Leaded has not been around for near 30 years unless you run avgas of some sort
Petrol has not been available for at least 20 years since we went onto a mix of light fuel oil with solvents blended into it because computer controlled fuel injected engine can burn almost any partially volatile liquid .
Thus what BSA said to use back in the 70's is not necessarily going to rignt in the 20's

And, how BSA designed engines in the 20's was not necessarily right in the 70's. Didn't stop them from trying.

experiment.

ive never run NGK B9ES on tbe street, but i will check now.

also B10

B8s are discontinued, so what the hell

I have no trouble finding blister carded N3Cs in the lawnmower section anywhere. Go figure.

the local Honda shop that last sold me two boxes of NGK B8ES plugs said that it was used in some of their dirt bikes

Kevin, use the #8 NGK Competition plugs, R5671A-8 ,not very expensive…They have the V cut center electrode and shorter ground strap.I use them in street bikes…

Is that anything like the "Hot U" plugs that ND used to sell? A shop put some of those in my Trident. Ran like s**t until I put N3s back in it.

Many NGK have a small notch in the center electrode…My race and street bikes and vehicles have no problems with them..Over the years I never noticed any difference between brands of spark plugs of the correct heat range in any engine..

AFAIK NGK is consolidating their range of plugs
The plain B (any number ) ES are being dropped as are the same HS for us iron heads
However they are still making the projected electrode BP in all grades and the resistor projected electrode BPR
My distributors tell me 2 different stories
One says then plain BR's are still going to be made & the others says that only projected noses are going to be made in future
Unless you are running 11:1's you should find the BP's will work fine, even better if you add some copper washers to index the plugs

Reverb, the 140E runs a hotter plug because of the different head design on the parallel port head. Triumph put out a service bulletin that specified Champion N5. An NGK B6 is the closest equivalent in their range. I've been running Champion N5C in my 78 T140E for the last 20 years.

Hi Htown70; I know that. Also I use Champion in my pre unit but with the dual plug head I tried with all those NGK due to I did not found a Champion equivalent for the D8HA (I mentioned all that in the other comment...)
Mr Healy presented a Triumph chart were B6 actually seems not the equivalent and too hot...and advocates for the B9 for the T140V
After the rebuild I will try with the mix of both for the 4 plugs in this head.