Is my new MT running too rich?

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Engine break in is like talking about motor oils lol

You should be able to break it in with one tank of fuel.

Start, let it idle until it comes up to temp. Shut off and let it cool.

Start after it's cooled off, bring up to temp and drive for 10min 1/4 - 1/2 throttle. Shutoff and let cool down.

Start , bring up to temp and bash it for 5-10min. Let it cool. Done. Tune after that.

Important to let cool completely before the next run during these steps.
 
Deluge said:
Yep, white is too lean, black is too rich. You want to hit it right between the two, which is like a tan color. It's important to do a speed run in order to get an accurate reading. Just do a wide open run, then kill the engine immediately to keep it from idling, then pull the plug. Simple as that.
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Is there a similar way to use the plug's color to check the LSN?
 
You can't tune the LSN by plug color, because by the time the engine idles it's loaded up with fuel, which washes away any tuning indication. This is why when tuning the HSN you have to kill the engine before it idles, or everything gets washed away.

To tune the LSN, you're looking for good throttle response. Start out rich and lean it out until all, or most of the lag is gone. I say most of it because some carbs just have a low end lag that you can't tune out, like the 668. But what you want is a smooth transition from low speed to high speed.
 
Ice_2k said:
Is there a similar way to use the plug's color to check the LSN?
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Hmmmmmm....

designed2survive said:
Peppy responsiveness is what you are looking for when tuning the LSN. As soon as leaning it doesn't provide any more improvement, you richen it at least 1/16 of a turn. Keep in mind that transition from low speed to high speed may still require minor tweaks to make it smooth.
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rcgasser said:
+1 I told him from the beginning on to tune the high speed from the plug even sent him a link to read the right plug color. Listening to others on the blog he wants to tune from listening to the engine. How are you supposed to hear and engine with a loud pipe on the side is beyond me!!!! But hey to each its own I guess. You can tell he is to rich on the low needle you are not suppose to see a puff of smoke every time you take off from slow or stop. This is not nitro.
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rcgasser said:
If you wait until it revs to drop the idle you will have gas on your plug therefore you will not be able to get the correct color. Killing your engine at high rev has nothing to do with it being hard to start when warm.
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Actually RCGasser, the small puff of smoke on take off and deceleration is considered good. Please don't laugh at someone when you don't know yourself.
 
Is my new MT running too rich?

designed2survive said:
Hmmmmmm....
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I didn't ask "how to tune LSN", I remember all the advice I already got. I was just asking if there's a way to confirm the tune using the plug. Similar to how many people recommend tuning the HSN by looking for the highest pitch but then you can confirm it by checking the plug. Not really sure what the harm was in asking that.

Deluge said:
You can't tune the LSN by plug color, because by the time the engine idles it's loaded up with fuel, which washes away any tuning indication. This is why when tuning the HSN you have to kill the engine before it idles, or everything gets washed away.
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Thanks for the explanation, very good info.
 
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Glad to see everyone's posts, these are very helpful and good for learning. I wasn't able to run my mt over the weekend to check my plug but hoping I will be able to do so this evening.

Thanks,
 
That's definitely weird. Take that cover off and check it out, if it's coming from a bearing, I'd say it's the bearing, or bearings that the clutch bell rides on. Those bearings take a beating with all that heat. Or maybe some fuel splashed onto the cover and got in. Just throwing out some ideas.
 
Deluge said:
Check the plug before you lean it out, just so you know where you're at and then tune from there. Break-in shouldn't take very long, unless you're putting around. When I break my engines in I just do a warm up run to get the engine temp up and then bash it. You want to put a load on the engine in order to properly seat the ring, you're not going to accomplish that if you're putting around.
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What do you think?View attachment 7801ImageUploadedByTapatalk1434473943.683473.webp

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I've removed the cover to visually check but I'm not seeing any leaks and not for long time since it is still new ;)

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