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This is what I meant when I said that I have the parts to do a twin plug.
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Gentlemen, this is what my plug looks like.
I do have a single prong plug that I could try.
 
That chamber looks beautiful, if it goes out to the full bore diameter (inner gasket diameter).
You can run it with only one plug wired up, but the dead plug needs to be no hotter than you are running.

Plug has too many miles on it to read for sure other than it is not too hot or hugely rich. You are in the ballpark.
Synthetic oils "burn" cleaner and make plug reading easier too.
What we see on the shell base ring is oil residue. I cannot see deep enough to read the insulator base.

The NGK plugs are slightly longer than the chinese 3 prong, but typically not a problem.

Steve
 
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The base of the insulator is the same color, burnt honey brown all the way down to the bottom.
Why wouldn't you use both plugs for ignition on the new head?



That chamber looks beautiful, if it goes out to the full bore diameter (inner gasket diameter).
You can run it with only one plug wired up, but the dead plug needs to be no hotter than you are running.

Plug has too many miles on it to read for sure other than it is not too hot or hugely rich. You are in the ballpark.
Synthetic oils "burn" cleaner and make plug reading easier too.
What we see on the shell base ring is oil residue. I cannot see deep enough to read the insulator base.

The NGK plugs are slightly longer than the chinese 3 prong, but typically not a problem.

Steve
 
if detonation is suspected, use a new plug, clean any carbon deposits from head, and try high octane gas
 
if detonation is suspected, use a new plug, clean any carbon deposits from head, and try high octane gas
I used high octane the first 2 tanks (+/- 1 gallon) It seemed better Ill admit but it was still there if I remember correctly. I have thought about using Marine fuel.
What do you mean by Detonation? I am fairly mechanically inclined but I'm still trying to learn all of the terms used by this community.
 
The base of the insulator is the same color, burnt honey brown all the way down to the bottom.
Why wouldn't you use both plugs for ignition on the new head?

If it is not jet black or blistered white, you are in a workable range. Need new plugs to fine tune jetting.

You know I mean the insulator inside the engine, inside the threaded shell?
I think you know this, but where you include a picture of the exterior plug insulator I thought I'd make it clear.

You could fire both plugs, it makes little difference.

I had a 1974 CR250 Elsinore many years ago that would foul plugs constantly because:
1) I used crappy oil,
2) I used crappy plugs
3) I jetted too rich (cuz more is better, right?)
4) I used too much crappy oil (cuz more is better, right?)
5) too much low speed trail riding

My answer, like most of us, was to MODIFY!
I stuck on a twin plug MT250 head with a cold plug for running hard and a hot plug for trails.
Didn't work. Hot plug runs hot even if no wire to it and when one fouls, they both foul.
Try out your ideas. Even when they don't work you can learn something.

Steve
 
If it is not jet black or blistered white, you are in a workable range. Need new plugs to fine tune jetting.

You know I mean the insulator inside the engine, inside the threaded shell?
I think you know this, but where you include a picture of the exterior plug insulator I thought I'd make it clear.

You could fire both plugs, it makes little difference.

I had a 1974 CR250 Elsinore many years ago that would foul plugs constantly because:
1) I used crappy oil,
2) I used crappy plugs
3) I jetted too rich (cuz more is better, right?)
4) I used too much crappy oil (cuz more is better, right?)
5) too much low speed trail riding

My answer, like most of us, was to MODIFY!
I stuck on a twin plug MT250 head with a cold plug for running hard and a hot plug for trails.
Didn't work. Hot plug runs hot even if no wire to it and when one fouls, they both foul.
Try out your ideas. Even when they don't work you can learn something.

Steve
Thanks, I will keep all of that in mind. I'm using Tractor Supply oil right now. I think that I am actually running it pretty lean at 40:1
Sorry about the mix-up with the insulator.
 
detonation (called 'ping') is when fuel burns too fast due to high compression or prematurely due to a hot spot in chamber acting like a glow plug

note, back in 70s when dual plug harley heads came out, we had to retard timing a bit because flame front had less distance to cover - so it does make a diff if you fire both at once, but I doubt these POS CDIs will put out enough to do both at once
 
My bike is actually doing the same thing but my plug looks good to me, I like to run just a tad rich to keep my stuff together ;)
 

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I have used the needle and the D clip to try and lean it out as much as I can, I'm not sure what 4-stroking is. I have heard other people talk about it but never understood exactly what it is.
I think that I can lean it out one more click on the needle though.

EDIT: I have noticed that it only seems to start the knocking after its warmed up.... but it still only does it at high RPMs.. if something was actually hitting wouldn't it do it at ALL RPMs after the engine warmed up?
needles aren't jets. get a jetting kit, the needle only affects idle and part throttle mixes
 
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