Input on plug chop photo

[Guest]

This is my first attempt at a plug Chop. I drove the bike about 3 miles to warm it up. I then ran at around 3500 RPM for 3/4 of a mile to get my Pilot circuit readings. When I neared the driveway to my house I pulled in the clutch and killed the engine, then proceeded to coast into the garage. I pulled the plugs and this is what I found. The tips are fairly shinny.

The bike was jetted with a DJ jet kit back in the mid 80's. Stock Mikuni adjustable needles set at 3 down. Pilots are 45.0. I just installed new 135 Mikuni mains jets because the DJ main jets were corroded from sitting for 18 years.

The Bike runs real strong, but I believe the pilot circuit to on the lean side. I do have a 47.5 pilot jets ordered. Mixture screws 4 turns out.

Your opinions?

[Redman]

Sounds like you have the procedure correct. ANd keeping the plugs in order and lableing them is a good idea also. And asking for opinions here on GSR is a good idea too. But what folks really need to see is the ceramic part of the spark plug, so pictures from an angle would see the cermaic part better, need to see the end around the elctrode and up the side and up into the plug some. And could get closer up view of the plugs if they were arranged right next to each other. Does your camera have 'fill flash'? Does your camera have 'macro' for closer up focus?

Maybe some folks here can give some opinion based on the photos, but closer up photos would be better.

[zuzu]

I took the bike for a longer ride. The outside temp here is in the 30's with spots of rain, not a fun day to do plug chops. Here is a new set of photos plugs with more of the ceramic showing. There is a Very ligh to light brown ring at the tip of each plug. All are close in appearance.

Thanks for any input.

[walt]

to me they all look correct. next would be check them again next summer in hot weather for the same light brown you have now. you do want the motor to spend a minute or so warming up from a cold start so that cams get a good oil flow before you ride away. having the pilot screws set at 4 turns out is a sign the pilots may need a step up.

[zuzu]

to me they all look correct. next would be check them again next summer in hot weather for the same light brown you have now. you do want the motor to spend a minute or so warming up from a cold start so that cams get a good oil flow before you ride away. having the pilot screws set at 4 turns out is a sign the pilots may need a step up.

Walt,

I have a set of 47.5 Pilot Jets on order.

I did the test again yesterday and #2 had a very slight grayish look at the end of the porcelain. I believe this to be lean. I am going to turn the Mixture screws out another 1/2 turn.
I started with the mixture screws 3 turns out. Since setting them 4 turns out, the throttle response has improved in the low to mid end range.

Thanks Again.

[Steve]

With the mixture screws 4 turns out, it's time to get the next larger size pilot jet. The 47.5s you have on order should do the trick. When you get them in, start with them two turns out. Sounds like you know how to procede from there. \\/


.

[tone]

Any stutter or holding back on the changover from primary to main jets this should show up anywhere around 3000 4500 rpm ????

[zuzu]

Any stutter or holding back on the changeover from primary to main jets this should show up anywhere around 3000 4500 rpm ????

Tone,
No problem there. In fact around 4500 is where the bike really starts to pull. The acceleration is nice and smooth starting out, till top end.

I did get a ride in today with the mixture screws 4 1/2 turns out. It seems that was to much. The plugs where sooty and the performance suffered. Also it would idle down and die once in a while.
I turned the Mixture screws back in to 4 out and she is running strong again.

Do these bike have more performance in warmer weather? It was about 40 degrees out today with lots of humidity.

Thanks

[Ironriot]

Cold dense air is always better for any engine so I'd venture to say that cold weather helps your engine really breath. Although it could be because your bike would be a little on the lean side

[chef1366]

What mods are on the bike besides the DJ kit?

[tone]

Tone,
No problem there. In fact around 4500 is where the bike really starts to pull.

Okay from that & the look of the plugs i'd say you are very close & doubt the primary jets need changing, around 4000 rpm would be the changover from primary to main jets so i'd leave the primary's alone do a plug chop at higher revs & see that the plugs tell us then :-D

one little known fact is that the latest unleaded fuels do tend to leave a little soot deposit even when running lean which makes things that little bit more awkward when looking at plug colour

hope it helps tone

[zuzu]

What mods are on the bike besides the DJ kit?

Chef

1982 GS1100E

1168 Wesco Bore Kit, Flow cut heads, K&N individual Filters, Super-trapp 4-1, Dyno Coils and wires, Kerker Jet Kit.

BTW, I have 12 Diffuser Disc's in the Super Trapp header.

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Tone,

I will try and get a full throttle plug chop this week. Problem is were are expecting lots of rain all week, so it might have to wait a few weeks.

[chef1366]

Are you running the stock cams?
We have similar setups. I run a 47.5 pilot and the idle adjustment screws out 2 turns and they could stand to go out another quarter turn in the colder weather.
The DJ needle is set at two notches from the bottom and shimmed lean a half notch.
The main is the DJ 138.
The bike pulls strong through all stages but stumbles of idle a bit when it's cold outside. The oil cooler doesn't help in the winter either.
I have Webcams at 340 lift and have them degreed via their instructions. (Can't remember the numbers.)

You might find the mains to be on the rich side.

[tomcat24551]

Zuzu--

Just curious--did you start the first plug chop run with new or freshly cleaned plugs?

Do you clean the plugs between runs (if so, how?) or do you read the sucessive runs without cleaning the plugs?

Thanks for the info.

Tomcat

[zuzu]

Zuzu--

Just curious--did you start the first plug chop run with new or freshly cleaned plugs?

Do you clean the plugs between runs (if so, how?) or do you read the successive runs without cleaning the plugs?

Thanks for the info.

Tomcat

Tomcat,

The plugs where like new and cleaned before each test with the wire wheel on my bench Grinder, then the porcelain was cleaned with starting fluid and a q-Tip.
I probable should pick-up a new pair of plugs for my next test. I wonder how much SPARK PLUG CLEANERS are at Harbor Freight?