Good, rich, lean and very lean spark plugs

[rij1]

Today I wanted to Check my plugs out of curiosity, so when I got home from riding I pulled My plugs and found these.
I have 2 pictures, One I took with a flash and one with out.
The plugs are from right cylinder#1 to left cylinder#4, 1-4




I pulled the carbs and cleaned all the jets and reset the Pilot screws from 0 - 3 turns out

[shinyribs]

You really have to look down inside to accurately read a plug. #3 & #4 are either very lean or your ignition timing is too far advanced. The white ground strap says so. #1 looks ...ok....but hard to tell for sure. #2 is lean but not as bad as 3 & 4.

Do you ever hear and pinging when you take off or accelerate under heavy load? Or a sound like valves rattling?

[rij1]

I thought the #1 was good too its more of a light grey, The #2 had a good heat mark on the ground strap that went from the tip to the bend so I figured the timing was good. Cant see in the pic though. But i'm not sure. The #3 porcelain and ground strap is more tan then white, The #4 Is white as snow both on the electrode, porcelain, Ground Strap and the base above the threads.

I haven't noticed any pinging maybe rattling. I'm not sure

The weird thing about this is I don't remember any difference in the plugs from when I did a compression check about a month ago. Maybe I wasn't paying attention at the time.
The only thing I have done since then is go from 91 octane back to 87 and used seafoam in a tank of gas once.

[Lucky 1]

What bike?
What exhaust and intake?

[rij1]

My info is in my signature area.

I'm about 100% sure my timing is set. I set it a couple months ago.

[tcazes]

its 1-4 sitting on the bike so 1 is very lean on the verge of detonation, 2 is definitely lean by way of the strap but not so much the electrode or bottom of the threads, 3 and 4 look like blow by if they are sooty so maybe that is why they may look rich but infact may be just fine? 1 doesnt look half bad really but 2 looks pretty sooty... its hard to read plugs did you do a chop or just pulled randomly at home? had it been idling a while before it was killed last?  i have an 82 with the stock box, 4 into 1 with baffles and same jets as you for the most part but stock i had 108s not 105s and mine seem slightly rich all the time. what were the mixture screws set at when you pulled the carbs? i set mine to 1.5 out and leave them. no real need to adjust individually really.

[rij1]

tcazes wrote

its 1-4 sitting on the bike

#1 is from sitting on the bike and the left outside plug and #4 to the outside right. My boots say #1,#2,#3,#4 from left to right sitting on the bike.
I have the pictures upside down intentionally though it may look like I uploaded them that way on accident.

tcazes wrote

did you do a chop or just pulled randomly at home?

I'm not sure what you mean But I pulled #1 then #4 Then removed the tank and removed #2 and #3.

tcazes wrote

had it been idling a while before it was killed last?

I rode all day then Held the RPM at 4,000 and killed the engine n coasted down the street and into my driveway.

tcazes wrote

what were the mixture screws set at when you pulled the carbs? i set mine to 1.5 out and leave them.

I checked the #4 pilot screw and it was set at 3 turns out as well as #1.

I set all my pilot screws 3 turns out now. I followed the MacGregor Carb Cleaning Services manual for this setting.

 

I did just see the service manual says 1 1/2 turns right now.



I pulled and cleaned the carbs yesterday and installed.
I installed cleaned plugs last night and rode about 2 miles and today I ran about 3 miles and held 4,000 RPM's about 90% of the time and Killed the engine and coasted down the street and into my driveway. I pulled the plugs again and it looks that the plugs are running lean on #3-4 and not too bad on #1-2. I might need to ride longer and normal riding to read them better..

I am using The NGK 2120 D8EA Nickel Spark Plug

[tcazes]

hey i guess i just got confused by how you listed the plugs my bad. what i mean by chop is exactly what you did when you cut the engine off at 4k and coasted in. id normally say you may need to go with bigger jets but sense it is only two running lean that puzzles me. but what i am thinking is what are the float levels? since it seems uniform from 1-4 could maybe leaving it on its sidestand have cause the bowls to be different levels since 1 would have more fuel than 2 and 3 etc? i say put the mixture screw at 2 and run it for a tank or two. 3 just seems so much... especially with a 4 into 1 pipe. i could understand needing to riched a bit but not quite that much. anyways keep us posted for sure




p.s. sounds like we have the same setup pretty much but mines an 82

d8ea plugs
4 into 1 pipe
stock air box
(i use a k&n filter in the box though)

i run 1.5 turns out with jets

35
68
108

[rij1]

tcazes wrote

p.s. sounds like we have the same setup pretty much but mines an 82

Mine is an 82 also


I wonder if the air cut offs are giving a problem..

[tcazes]

Good possibility. If they are the original ones then the rubbers may be rot and that very well could be the problem.

[rij1]

Well I went for a 10 or more mile ride and came home and pulled the plugs and it has the same pattern.
I rode easy and aggressive to get a better reading and no change.

Is this a carb issue or could other things cause this?

I checked for air leaks around the boots and my compression is good.

[rij1]

Question about the seal ring on the carbs. All mine were installed with the flat side up. The Macgregor carb manual says to install the rings with inner lip up. Which way does everyone usually install them.

[tcazes]

if this is the same manual that said go three turns out on the mixture screws i would ignore it and go look at the brakedown in the manuals on the home page.... im not sure what seals you are talking about so im of no help really.

try and maybe switch the spark plug wires?? put the outer two on the inside and viceversa may have to do the swap at the coil itself since the boots are different but that would rule out coil pack issues....

[rij1]

It is. But it's the carb manual from this home page that I downloaded.

The seal ring is the seal under the round cap on the carbs.
I just completely disassembled the carbs and inspected and cleaned. I also did the air cutoff block off mentioned in the manual. the only thing I found wrong with the carbs was the  Accel Pump diaphragm on the #2 carb bowl is cracked up.
Should I try and replace the cut offs or leave them blocked?

[rij1]

I swapped the wires some time ago cause of another issue I cant remember at the moment.

I decided on not having the air cutoff block and just applied a thin layer of silicon to the diaphrams. I completely went through the carbs and put them back together and rode 25 miles and pulled the plugs. The same darn thing. I don't know what to do with this bike anymore.

[tcazes]

hmm idk what to tell ya bud