Topic: Spark plug pics / glazing

[Eddie]

These plugs look like they are wet but its a shiny glaze... thoughts? 75 CB550, Pamco ign. stock air box, stock coil.  Is this caused from all the additives in the gas we now get ?

[jpfrk2001]

Looks fine to me. Shows no evidence of running lean. And that's good.

[Eddie]

after about 200 miles the plugs glaze up and it runs semi ruff,  clean the plugs up and it runs much better. Put in DR8ESL's in... 5ohm plugs and 5 ohm plugcaps.

[2wheels]

Are you using oil?

[Eddie]

No oil burning at all. even after 1500 miles it's very clean looking as well. they look wet but are not..

[2wheels]

No oil burning at all. even after 1500 miles it's very clean looking as well. they look wet but are not..

Ok, well I'm out of my league all ready.   But I will ask this just so the smart members here will not have to assume.
What's the spark plug gap set at.  Have you verified the timing / advance with a timing light.
Good luck.

[TwoTired]

Are you using a fuel additive?  If so, stop.

Looks like the plugs aren't getting hot enough to self clean.

Why aren't you using the recommended hotter plug D7EA (or DR7EA) for the Cb550?

[flybox1]

Why aren't you using the recommended hotter plug D7EA (or DR7EA) for the Cb550?

Looks like he is TT

[TwoTired]

Why aren't you using the recommended hotter plug D7EA (or DR7EA) for the Cb550?

Looks like he is TT

Really?  Then why did he say this?

... Put in DR8ESL's in... 5ohm plugs and 5 ohm plugcaps.

[Eddie]

I switched out the D7's for the DR8ESL's as pre Hondamans recommendation, had them laying around thought I'd give them a try.  Timing is spot on, I try to not "lug" it by keeping the rpms up.  Not using any additive .  I think it actually runs better with the 7's....when they are clean.

[TwoTired]

Spark plugs will self clean at the right combustion temps.  The porcelain needs to stay white for more distance from the center electrode than what the spark gap is.  The porcelain is an insulator, and if you cover it with conductive material, the spark travels the least difficult path to travel.  Carbon is a conductor.  In short, your plugs are fouled/fouling, due to an over rich mixture, which cools the combustion and leaves unburned hydrocarbons to deposit on the plugs.  Most likely, the rough running is an artifact of the fouling plugs.

Time to review the tune up check list, air filter restriction, carb settings, and carb cleanliness.  I'd also go back to the D7 heat range, unless you plan to spend most of your time at high power race settings and in hot weather where the engine cools less.

Describe what is your normal type/style of driving or operation of the vehicle?  Ever use full throttle?  What percentage of the time?
What is the history regarding the carbs?

As to what glazes them...  If it is just standard gas (ethanol blended?) that may be contributing to the cooler burn temps.    Maybe even some of the additives in your oil is depositing on the plug tips.  Perhaps intake valve seals are leaking.

[Eddie]

I drive it to work as much as possible... 8 miles each way. Carbs were rebuilt spring of 2012. timing is right on, air filter was changed at the same time. Only has 16k miles, I've only put on 2500. Very rarely have I gave it full throttle and run it up to 7k rpm, but dont really baby it..  I thought the ESL plugs were kind of a range between 7's and regular DR8EA's.  Guess I could try the DR7's since I have the 5k plug caps.  Great point on the carbon ... I work on electronics... power amps and such and have had to cut away burnt pc boards that were burnt..

[Jerry Rxman Griffin aka MuthaF'er]

Why resistor plugs AND caps?

[Eddie]

need a total of 10k load..  orig plus were not resistor... caps were 10k.  cant find the angled caps in 10k any more, at least in NGK.

[TwoTired]

Very rarely have I gave it full throttle and run it up to 7k rpm, but dont really baby it.. 

You know to me, this sounds like a contradiction.   

Anyway, 9K is red line, and after it is warmed up, I feel bad if haven't gotten up there during just about any ride.  It seems to really appreciate a good flogging. 

[Eddie]

I think I may have taken it to 7k twice....buzzes my balls so bad it makes me afraid for that little motor.. Lol !

[evanphi]

I think I may have taken it to 7k twice....buzzes my balls so bad it makes me afraid for that little motor.. Lol !

Thats the best part about these old bikes! Get the revs high and BAM... instant sex-machine.

[lucky]

Yeah......Sex machine!
JAMES BROWN -"SEX MACHINE"- 1981

[flybox1]

Why aren't you using the recommended hotter plug D7EA (or DR7EA) for the Cb550?

Looks like he is TT

Really?  Then why did he say this?

... Put in DR8ESL's in... 5ohm plugs and 5 ohm plugcaps.

I was referring to the original plugs in the top photos.  those are/were the right plugs.

[Duanob]

Very rarely have I gave it full throttle and run it up to 7k rpm, but dont really baby it.. 

You know to me, this sounds like a contradiction.   

Anyway, 9K is red line, and after it is warmed up, I feel bad if haven't gotten up there during just about any ride.  It seems to really appreciate a good fogging. 

TT I hope you meant FLOGGING?

7K RPMs is nothing. I try to reach that on my hiway rides and frankly I think I'm only doing 75 - 80. Around here you get passed a lot only doing 80. Or do some spirited take offs up to 8K+ every now and then. Anything to clean the carbon out of the cylinders, works wonders and the bike enjoys it as much as I do 

[TwoTired]

I think I may have taken it to 7k twice....buzzes my balls so bad it makes me afraid for that little motor.. Lol !

Then you have a lousy seat.  (Or, perhaps a very enjoyable one!?)  I never thought of dragging my balls on the frame.  I suppose vicarious pleasures are where ever you find them.   
Still, most who ride the CB550 (or any SOHC4) remark about how smooth it is compared to other bikes.

The RPM thing is relative, to both size and design.  Big torquey motors usually turn lower RPM and don't last long at high RPM.  Never mind shaking the riders teeth out of the jaw.  (Or, joy to the nether region.)
Smaller motors turn higher.  The SOHC4 is naturally balanced by design.  I have 1 cylinder 4 cycle model airplane motors that IDLE at 2-3000, and do 12,000 @ cruise.  The 2 cycle motors turn about 5000 rpm higher.

The SOHC4 design allows operation at or near red line for routine bursts of power.  As with all engines, running at peak output constantly will mean lower rebuild intervals.  I have 47,000 miles on one of my CB550s.  And it's been routinely flogged for all of those miles.  When I was younger, I treated the throttle as though it were an on/off switch for anything other than steady cruise.  And, the trans was down shifted when the throttle was "on".  That tough little motor gets my earnest respect.

[Jerry Rxman Griffin aka MuthaF'er]

Resistor plugs, resistor caps, colder plugs. WTF! Get rid of the resistor plugs if you are running resistor caps and use the '7' plugs. You gotta let it fire the plugs properly. It's like you are turning down the faucet but expecting to get a higher volume of water.

[TwoTired]

Resistor plugs, resistor caps, colder plugs. WTF! Get rid of the resistor plugs if you are running resistor caps and use the '7' plugs. You gotta let it fire the plugs properly. It's like you are turning down the faucet but expecting to get a higher volume of water.

Jerry,
The cap resistors for the CB550 are 10KΩ, for a coil secondary loop resistance of 20KΩ plus the coil resistance.    It works fine that way.  However, replacement 10KΩ caps are very hard to find.  5KΩ caps are widespread.  This would lower the loop resistance to 10KΩ, increasing the current draw from the coil and charging system, raise the coil heating for most 550s, and increase the spark plug electrode erosion.

Resistor spark plugs are easy to find, and have a 5KΩ resistor in them, restoring the stock coil's secondary loop added resistance to the original 20KΩ.

I do agree that colder plugs are misapplied here.

Either, the OP has a carb mixture issue, or he isn't letting the engine make the power (heat) needed to get the plugs to self clean.  Another possibility might be intake valve seals leaking.

But, I'm going with wrong plugs, too much choke operation, and with 8 mile runs, low combustion chamber heat.  I wouldn't be surprised if the OP also found the brown mayo around the oil dipstick.

I think the OP should announce what the pilot screw setting current is.

[Eddie]

No "brown mayo" around dip stick. screws out 1.5 turns. Never have to use choke to start, just hold the throttle open a little after starting. There is no hesitation whether I give it a little gas or a bunch.  Guess I'll have to flog it a little harder...anyway, waiting for new plugs to arrive.

[TwoTired]

screws out 1.5 turns. Never have to use choke to start, just hold the throttle open a little after starting. There is no hesitation whether I give it a little gas or a bunch. 

The bike's carbs are definitely set too rich then.  What's the outside air temp when starting?
Slow jet size?
Slide needle position?
Main jet size? (marked or actual?)
Emulsion tube bleed holes clear?
Air filter clean as new?
Filter box inlet clear?

Are the carb internal components aftermarket or factory original?