Sparkplugs.....or Why Bother

[Rio Wil]

The phat lady is a constant source of amazement!!

Below are two photos of spark plugs just removed from the Valk ( a plugectomy... ).

The plugs have 126K miles and I changed them simply out of guilt.....no power problems, no fuel mileage issue, no idle problems.....just sheer guilt. They have never been cleaned, matter of fact 5 of the 6 have not even been unscrewed in that time, I did remove one plug at about 60K miles just to see if they were frozen.  You can see just a bit of never seize on the threads......worked good..

The plugs were gapped at .032 new and now are about .034-.035......
These are stock NGK DPR7EA  9 from O'Reileys Auto Parts for 2.49 each.
The bike has 226K.....so I am happy with the plug color and condition....

Oh....the new plugs changed nothing......but I do feel better

[Bone]

Couldn't wait that long your strong. Unscrew mine each fall just so they will. I broke down at 70k and did the plugectomy.
Wonderful machines.

[Bagger John - #3785]

Couldn't wait that long your strong. Unscrew mine each fall just so they will. I broke down at 70k and did the plugectomy.
Wonderful machines.

I do mine every fall when it goes into winter storage (so I can squirt a bit of oil into each cylinder) then check the gaps every spring when breaking the bikes out for the season. They get cleaned and a small dab of anti-seize applied to the threads.

Used to change them every spring but that was with fewer bikes and a lot more accumulated miles per year. I may have re-gapped two plugs in five years.

[Chrisj CMA]

Sparkplugs

[Tfrank59]

Well I changed mine, along with many things when I first bought my bike, just to see what's going on in there (are they all tan, are the gaps correct, are the threads OK – put a little antiseize, etc).  For those of us who purchased our Valk used, once you've change the plugs, you know what's in there and you know that item is good to go, then on to the next thing.  For me, it's as basic as changing the oil in any new vehicle you buy.

[h13man]

Recently changed mine do to one fouled out @ 9000 mi. Manual calls for 8000 mi. intervals. At $13 a set I guess I'll trust the manual recommendation.

[Chrisj CMA]

Recently changed mine do to one fouled out @ 9000 mi. Manual calls for 8000 mi. intervals. At $13 a set I guess I'll trust the manual recommendation.

8,000 mi interval.   No way, for the last 13 years I have been changing them every 50 to 60 k and they always look like new when I toss them in the trash.

Something other than plug age/miles caused that fouling

[CoachDoc]

Changed mine at 50k.......went with the Iridium plugs from NGK. Definitely won't need to be changed again for the life of the bike or 100k, whichever comes first.....lol

[skygog]

I did not know they could be changed, thanks  103,000 now.

[Oldnick]

To me it looks like why bother, except that  for under $20 you have new plugs. They look very clean, but  insulation can break down etc.

For me I would buy a new set, have them on me and  replace if you get trouble.

OTOH,  for the cost, just doi it qand keep the old ones in case....

I reckon it's amazing that the plugs look like that after so long.Creds to Honda, I guess.

Nick

[Daniel Meyer]

Honda would like you to change these plugs (or at least r&r) at the manual's recommended interval so those nice steel plug bases don't permanently mate themselves into your nice aluminum head...

Note, they are also resistor plugs which, if falling out of spec will effect timing even though they look okay. It's as easy to change them as check them.

I do mine about once a year...or so...sometimes...mostly.

[Rio Wil]

Changed mine at 50k.......went with the Iridium plugs from NGK. Definitely won't need to be changed again for the life of the bike or 100k, whichever comes first.....lol

So I wonder, do the makers of 100K plugs recommend they be removed ever so often to check for seizing up .....or do they rely on the plating on the plug to resist corrosion and seizing?

The plugs in my F150 are supposed to be 100K plugs.....but that is another whole f'ed up story....stupid ass Ford engineering..

[98valk]

NGK makes great plugs.
however looks of electrodes mean nothing. its all about the resistance of the resistor. new NGK plugs usually are about 4.5-4.7K ohms. if still in that range at 100+k miles, then they are well made plugs and live up to their rep.
case in point, I have a set of autolites installed. a few days ago it was very hard starting when cold and ran really rough, until some temp got into the cylinder then it ran and idled like nothing was wrong. well pulled some plugs, a few were 7k ohms and the others were still as when new at 3.5k ohms, these type have a reduced size center electrode.
When I install plugs I always check the ohms and write it down. in fact the set of autolites that I just took out, when I bought them, one plug was over 7k ohms and the rest were 3.5k range. had to go buy another one.

[gordonv]

I know almost nothing about plugs other than they come with a resistance.

You actually know what the resistance should be, and you measure them up before installing, so you have a match set? Does it actually matter or do anything?  ???

Now with the Iridium plugs I'll be installing in the spring, the tips are made from a material that supposedly withstands the arch of the spark without wearing down. Therefore the gape and the sharp edges of the electrode stay intact (the spark likes the sharp edges to jump to, that's why regular electrodes round out from use). I think I'll also try this measuring of the resistance if I remember, and record each plug and the cylinder they go into.

[jdp]

Man these bikes are the best,everyday I hear something amazing about them,we sure are lucky to have one.

[nogrey]

I know almost nothing about plugs other than they come with a resistance.

You actually know what the resistance should be, and you measure them up before installing, so you have a match set? Does it actually matter or do anything?  ???

Now with the Iridium plugs I'll be installing in the spring, the tips are made from a material that supposedly withstands the arch of the spark without wearing down. Therefore the gape and the sharp edges of the electrode stay intact (the spark likes the sharp edges to jump to, that's why regular electrodes round out from use). I think I'll also try this measuring of the resistance if I remember, and record each plug and the cylinder they go into.

That's interesting stuff there. I just received a set of iridium plugs that I ordered a few days ago. I'll measure mine before putting them in and we can maybe compare notes? Might be good information to keep in the valk book. Sure can't hurt. Anyway, interesting theory. I noticed that the iridiums I received have very small electrodes that come to a very sharp point.

[gordonv]

I noticed that the iridiums I received have very small electrodes that come to a very sharp point.

If I have it right, and the sharp edge is where the spark goes. Then the iridium is strong enough to stand up to the arch. There is no reason for anything more, as that edge will not wear away.

I remember reading NOT to check your gape (do it VERY carefully), as it is also very brittle, and can break if you try to force a gauge in there. Use the electrode bender to adjust the gape. So knowing that, do it very carefully.

I keep a little note.txt in my service/motorcycle folder, and record everything I do to my bike, along with notes of interest (Valk rim compatibility, oil filter, tire size, spark plug, etc. etc.).

[Kunkies]

Great discussion, thread.  I found this article on what our spark plugs are telling us to be very informative and well written.  Check it out here:  http://www.totalmotorcycle.com/maintenance/sparkplugs.htm

[98valk]

Great discussion, thread.  I found this article on what our spark plugs are telling us to be very informative and well written.  Check it out here:  http://www.totalmotorcycle.com/maintenance/sparkplugs.htm

an excellent way to read plugs.
http://4secondsflat.com/Spark_plug_reading.html

[O-B-1]

case in point, I have a set of autolites installed. a few days ago it was very hard starting when cold and ran really rough, until some temp got into the cylinder then it ran and idled like nothing was wrong. well pulled some plugs, a few were 7k ohms and the others were still as when new at 3.5k ohms, these type have a reduced size center electrode.
When I install plugs I always check the ohms and write it down. in fact the set of autolites that I just took out, when I bought them, one plug was over 7k ohms and the rest were 3.5k range. had to go buy another one.

A friend of mine is an auto mechanic by profession. He said it was best if I avoided Autolites altogether due to quality issues.
He said to get NGK's, even for the 1977 Chevy C20 Crew Cab I just stuffed a 1988 GMC 305 TBI & HD Turbo 400 into.

[98valk]

case in point, I have a set of autolites installed. a few days ago it was very hard starting when cold and ran really rough, until some temp got into the cylinder then it ran and idled like nothing was wrong. well pulled some plugs, a few were 7k ohms and the others were still as when new at 3.5k ohms, these type have a reduced size center electrode.
When I install plugs I always check the ohms and write it down. in fact the set of autolites that I just took out, when I bought them, one plug was over 7k ohms and the rest were 3.5k range. had to go buy another one.

A friend of mine is an auto mechanic by profession. He said it was best if I avoided Autolites altogether due to quality issues.
He said to get NGK's, even for the 1977 Chevy C20 Crew Cab I just stuffed a 1988 GMC 305 TBI & HD Turbo 400 into.

these are the ones I use
auto lite 4164 which has a necked down center electrode and then mod the side electrode.
http://www.sparkplugs.com/product.aspx?zpid=7776
11. N ECKED DOWN
CENTER ELECTRODE
Tapered high nickel-chrome alloy tip
combined with copper center
electrode
produces
hotter, sharper
spark for
easier
starting
and on-road
performance.

any specilaty plug, platimun,  Iridium, etc., only work because other parts of the ignition system are weak. (The valkyrie ignition is a weak system as stated by Dyna ignition). This is in Dr jacobs book.  those exotic metals have very high resistance, hence why the center electrode has to be so small.
hotter coils, better wires are the answer and modified plugs, which I do for all my vehicles. I was using a set of coils from a blackbird, quicker accel, but they would burn out the dyna ignition, so back to stock now. They wouldn't hurt the stock ICMs.  Also measure the ohm resistance btwn plug brands, they are all different.  http://www.musclemustangfastfords.com/tech/0207mmff_tech/index.html    by David Vizard tells why the plug mod works.

[nogrey]

I measured my Iridium NGK's that I received yesterday before putting them in. They were all 5.1 to 6.1 ohms. NGK DPR7EIX-9
Another thing worth mentioning: I was reading some older threads and they all talked about things like using anti-seize, copper, zinc, nickel, aluminum etc. I think the bottom line was to use whatever you have but use it. The other thing mentioned was how to properly seat the plug, which had all sorts of variations of opinions. None of them mentioned the one that actually came on the NGK spark plug box that I received my plugs (not the individual box, but the outer box that held 4 plugs). It had a pictorial diagram indicating that the plug should be threaded in by hand until seated, and then tightened 1/4 more turn. Much the way one installs an oil filter. This eliminates the concern for over-torquing due to the use of anti-seize.

I started it up after installing them and the bike took off so fast that it was just a red blur. (Ok, that last part isn't really true)