Plug inspection

Hey Gents / Ladies--

Little test - based on plugs alone - what would yall say my symptoms would be.

Plugs about 1k miles old.

If not already done, would first perform clear tube test to verify fuel levels being in specs (not too high).

And with brand new plugs, would watch for fat blue sparks on each plug while spinning over the engine. As this will provide some preliminary indication as to overall health of the ignition system.

Sooty plugs may result from weak ignition (for whatever reason) and/or improper fuel mixture (for whatever reason) and/or insufficient compression (for whatever reason).

Good Fortune!

Well --

I have been chasing a few different things here.

I overheated on the highway going full throttle while having to pull in the clutch and slam the breaks due to rush hour traffic idiots.

I was concerned that I was running lean to cause an overheat. I pulled the plugs and found this - what seems to be a rich mixture.

I checked out my oil glass, and I am very low on oil. Now... I have had to drain the oil 2 times due to replacing my trans cover, and I lost a bit through my tach seal, so it is hard to tell if I am low because of loss or because of burn. And honestly I have looked at the spark plug charts, and I was not sure if these were rich plugs.... or oil burning plugs.

I will do a clear tube test... did one around the time I installed a brand new ignition system last winter/spring.

Looks like I should get some new plugs, change my Oil, and check my spark / timing.

I think I see a slight touch of oil on the first plug. Not enough to foul. The other's look like fuel. Being one is clean and the others are black, suggests it's a carb issue or valve adjustment issue.
How old is the engine? New rebuild?
Steve

Hey Steve -

I bought it from somebody who claimed to have done a full rebuild on the engine.

It has been bored to 1045 (1 mm over, 71mm 10.25 :1) with new pistons and rings, new cam chain. The head has been rebuilt with replacement valves. New gaskets & seals. The crank shaft was checked and found to be in excellent shape, most likely because of the low milage. It has a brand new Vance & Hines chrome 4 into 1 exhaust. The carbs have been rebuilt with full performance kit and up graded with brass fuel inlet fittings. The clutch has been replaced with an EBC kit. New O-ring chain.

That was in the listing from the person I bought it from. Nobody needs to tell me not to buy a bike like this again... hindsight 20/20 I would have bought a bike needing work and done it myself. But I wanted something ready to ride. So be it....

Some of the work stated above looks to have been true... while some of it I am not sure... as the clutch went and it was not a new EBC kit... but hey you live you learn.

I had the carbs cleaned ultrasonic and tuned synced by a friend before I had the necessary tools last summer when I was dealing with a failed Stock electronic ignition. The carbs were actually set up right, and my issue was bad coils/and faulty ignition. The was all fixed with the dyna kit i installed. I now have a sync gauge, and I checked it last night, they are still in sync via vaccuum. I have likely put 1k miles or less on this bike since its rebuild. I have done a valve check recently and valves are all in tolerance.

My mixtures could be off.... Pretty sure all the pilots are set at 1 1/4 turns. Unknown what the jets are in there. I am going to have to play with this a little more.

But hey. I am learning as I go.

Bear in mind that even with everything else in perfect as-new condition, perfectly sized jets, perfectly adjusted screws/slides, perfect ignition, perfect compression, and perfect valve clearances, etc., too high fuel levels will over-ride all that other perfection. Which is why I would start with the clear tube testing.

Good Fortune!

Do your clear tube test for the floats. You may have to look at the pilot jets to be sure they aren't mismatched. If it has a new top end, the rings may not be seated yet. A lot of times a bike will "lean out" after a few hundred miles. When I do a jet change I try to put 100 miles on it before changing them again.
Pics?
Steve

word. easy enough. I'll post back tonight when i get home

M

From my experience:

Nº1: Looks good
Nº2: Too rich plus oil. Bad valve guide seal?
Nº3: Too rich
Nº4: Too rich

Is the bike running OK now?

When the PO said they rebuilt the top end, the probably meant 60,000 miles ago. Seriously, though, the valve clearance needs to be checked almost as frequently as the oil is changed. So, in other words, it's time to do it now.

When I burnt up an exhaust valve it was in a situation like you describe, full throttle on the highway, into a head wind, up a hill--the bike suddenly lost power and began to overheat. After cooling it restarted OK but kept fouling one plug. The beauty of a 4 cylinder bike is that I was able to ride the 300 miles home. That cylinder still had 60 PSI of compression even with a huge chunk of exhaust valve missing.

After you adjust the clearances, check the compression... If one cylinder seems too low and adding a spoonful of oil to the cylinder doesn't bring it up, then you might have a burned valve too.

Hey Jackleberry -

Bike is running great now. First time I have had this kind of issue.

The PO was a shop. They built this bike and told me it was a basketcase. I can tell that the bike was built, and sold. Less than 500 on the rebuild before I bought it, basically an engine break in.

I checked the clearances a few weeks ago. They are in tolerance. Here is a pic of last night, warmed up. And idling at 1k.




ill play more with it tonight.