Combustion chamber conditions and piston spark plug carbon build up.

[Zingzing29]

So what's going on here to cause all the carbon build up(right) verse the normal tacky oil build up (left).

Whys is it half and half carbon/oil residue

 

[GW's Motorized]

It looks like it could be the angle of your spark plug.

 

[Zingzing29]

It looks like it could be the angle of your spark plug.

That an interesting proposition. Especially since I took special care to make sure it was facing the rear of the cylinder. Lol

 

[Amwicr]

That head is really gunky, you must be running way rich.

But what do I know anyway

 

[Zingzing29]

So what's going on here to cause all the carbon build up(right) verse the normal tacky oil build up (left).

Whys is it half and half carbon/oil residue
View attachment 201267View attachment 201268View attachment 201279View attachment 201280

#70 main
3rd notch down on a 4 position Needle (richer)

 

[Zingzing29]

That head is really gunky, you must be running way rich.

But what do I know anyway

32:1 Lucas semi
90 rec fuel

 

[Zingzing29]

I did like the cir clip raised one position (leaner). #70.
It's about to be winter so I'm not doing any tuning until then

 

[Zingzing29]

So how do I get cleaner combustion

 

[Chainlube]

That's all normal. Good wash pattern on top of the piston. You're right, one position leaner on the clip.

 

[Zingzing29]

That's all normal. Good wash pattern on top of the

That's all normal. Good wash pattern on top of the piston. You're right, one position leaner on the clip.

piston. You're right, one position leaner on the clip.

So now I got a good sealed engine. My next question would be this pipe I got from mz Miami motor bike. (I don't think they make them anymore) anyways. I have a welder. How do I weld this together properly with tube lengths and such. I'm trying to clean up the dead spot in transition from mid range 5-6k to top end 7-9k. I've seen the dyno results on them.