ALCOHOL PLUG READ

[stroking]

How does these look ?

 

only ran on alky

 

[tedd1]

Looks to me like you are a little bit lean and border line on timing. I would open PJ a round and look again. That may cool it down a enough to leave the timing alone.

Look for the black spot on the end of the threads to be about 1/3 of the way around (fuel) and I don't like the crust on the electrode (timing) to be past the bend.

Check your pipes for temp at the end of a run. They should be the same temp. Don't be afraid to tune each cylinder separately.

[stroking]

Looks to me like you are a little bit lean and border line on timing. I would open PJ a round and look again. That may cool it down a enough to leave the timing alone.

Look for the black spot on the end of the threads to be about 1/3 of the way around (fuel) and I don't like the crust on the electrode (timing) to be past the bend.

Check your pipes for temp at the end of a run. They should be the same temp. Don't be afraid to tune each cylinder separately.

 

 

the two plugs that are pictured together are from a stock cylinder with two Pjets ones closed all the way and the other is open all the way.

 

the plug by its self is out of a 4mil cub,it has one Pjet open all the way....can i raise the needle up or do i need to drill the main bigger?

 

both timing are on +12

[tedd1]

See below...

Edited September 22, 2010 by tedd1

[tedd1]

I edited my previous post mainly for clarity and terminology.

I also made the starting point a little richer for safety.

 

Watch for indications of heat. These indications may take several passes if you are making 300' passes and make come sooner if running longer distances. Clean/light colored areas of the plug are hot areas and dirty/dark areas are cooler. More timing/less fuel = more heat. Less timing/more fuel = less heat.

 

Too much heat and areas of the plug will glow and cause detonation.

[stroking]

ok i thought if a alky plug is rich it will look new with almost no black area and a black ring all the way around means LEAN ?

 

guess i've been reading it wrong

[stroking]

ok i thought if a alky plug is rich it will look new with almost no black area and a black ring all the way around means LEAN ?

 

guess i've been reading it wrong

 

 

what should the pipe temp be ?

[sheefreak]

Two very nice diagrams, the heat diagram is just worded backward. The richer it is, the less black will be on the plug. I posted this recently but here is a picture of a plug for further reference. You can see the timing mark as well. I could have put a lot more timing to this motor.

 

[J-Madd]

Yeah, if its way rich, you can run it all day long and it'll look like new. I've ran an entire race, including test and tune and never put any color on the plugs. Bike still ran good. Probably could've picked up a few hundredths leaning it down a little, though.

[tedd1]

Yes, I am an idiot. I wrote it backwards, I apologize and can only say that I get confused easily...

Edited pics for wording...

 

I have some pics that might help explain.

 

Looking at the ground strap from the side:

 

Looking at the plug from the thread end:

Turn the plug so that the ground strap is at 12 o'clock. The black, sooty area should then be between 9 & 3 o'clock.

 

Read <HERE>. Good info...

 

I run a 421 cub on alky with 39 Kiehins with a single PJ on each, EGN needles on the 2nd clip, 60 pilots, 118 mains, power jets open to 4 turns. Timing at +8.

Typically, I start with PJs open 4 turns. Watching plugs and exhaust temps, as the day cools, I will close PJs another round or so, a little at a time. Also, the right side usually wants about a 1/2 turn more fuel than the left side.

 

It is difficult to tell for sure looking at pics, but I still think you are a little lean (the left plug looks leaner than the right) on the stock cylinder bike and have a tad too much timing.

 

I can not tell for sure about the cub plug.

 

As stated before, don't be afraid to tune each cylinder separately.

 

I hope this helps...

Rick

 

 

Simply, more alky will wash and cool everything down.

[MilleniumPerformance]

I coulnd't have said it any better Tedd. Great post.

[stroking]

thaks for the help

 

oh what should the exhaust temp be ?

 

this is a 1/8mile pavement only bike.

[drag+6blaster]

thats clears things up for me .I've been dialing in my project Blaster wrong the plug ..The plug is clean as new but it is pepie down low ... I thought it was lean on the top end throttle range.. went bought richer jets on my way right now to get leaner jets .. i was pulling my hair on that one

[stroking]

these are out of a stockcylinder alky motor

 

+12 timing

 

125psi

 

 

 

 

do they look ok