Break In New 80cc break in weird noise + low performance?

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Als
I can feel hot air on my knees and I swear sometimes my leg feels wet. Its also leaking slightly from the spark plugs hole.
Also, how can I make my throttle better? The throttle grip seems to have play. I have to twist it alot to get minimal throttle and wot requires a small amount of movement from half throttle to engage.
 
Als

Also, how can I make my throttle better? The throttle grip seems to have play. I have to twist it alot to get minimal throttle and wot requires a small amount of movement from half throttle to engage.

Adjust all the adjusters fully out to take out some of the slack, and then if that still doesn't do it:
If you know how to solder you can shorten the length of cable which sticks out of the housing, cut and solder on a new end piece doodad made out of some small diameter tubing or a wrap of wire.
Cut or sand or whatever the new end piece doodad until it fits in the carb like the original did. I haven't ever had one come loose.

If you don't solder you can buy a new throttle with a throttle tube which has several different spots to place the throttle-side end piece doodad which take up varying amounts of slack.

I got some off brand cnc aluminum 1/4 twist throttle from china on ebay, that I think works great. It has 5-or-so different spots for the cable doo-dad to go. There are also some with a roller bearing for smoother twist. I like full throttle at all speeds so 1/4 twist is good!
 
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if spark plug leaks, then it is not tight - maybe you lost the compression seal on the plug?
 
if spark plug leaks, then it is not tight - maybe you lost the compression seal on the plug?
I did actually. I just realized that. I'll buy buy new plug. Should I have have gasket underneath the 4 head bolts around the piston chamber?
 
Not to be random or anything but the noise you might be hearing is gears. A noize you should be realy concerned about is I loud hissing that comes and goes every few seconds I learned the hard way what it was. It is the piston tearing into the cylinder wall. Unless it is a manufacturing defect you shoulnt hear it on a new motor. It only happens when the fuel to air is too lean or there are air leaks that dont get fixed.


A really effective way to check for air leaks is to take off the air filter start the engine (there CAN NOT be any dust in the air, engine damage) no choke make sure the idle is stable then put your finger over the air intake. The engine should stop the moment the intake is sealed by your finger. If it doesnt stop right away you may have air leaks.
 
Not to be random or anything but the noise you might be hearing is gears. A noize you should be realy concerned about is I loud hissing that comes and goes every few seconds I learned the hard way what it was. It is the piston tearing into the cylinder wall. Unless it is a manufacturing defect you shoulnt hear it on a new motor. It only happens when the fuel to air is too lean or there are air leaks that dont get fixed.


A really effective way to check for air leaks is to take off the air filter start the engine (there CAN NOT be any dust in the air, engine damage) no choke make sure the idle is stable then put your finger over the air intake. The engine should stop the moment the intake is sealed by your finger. If it doesnt stop right away you may have air leaks.
That's not particularly good for checking for a leak, when you put your finger over the intake you completely shut off the fuel flow to the engine, without air going through the throat of the carb gas just won't get sucked in.

In other words doing that should shut off any engine immediately, but only because you took away the actual fuel to the combustion, air alone doesn't burn it just delivers the oxygen gas needs to burn.
 
It works for my engine thats how I found the intake manifold leak I could hear the hissing from it and the engine ran bad so I knew there was a leak. And I found it. Must have been another lucky find.
 
Hello all,

So I am relatively new to the MB scene and to this forum but everyone here has been a great help. So I bought a new 80cc engine off eBay (just a basic kit engine). I know these engines require a break in period but i have a few questions. Here are my specs.

100:1 Opti2
C Clip is in the middle notch(every setting is same performance)
Stock NT Carb and jet


So the engine performs but it is very slow. Uphill is a struggle and it feels like its going to die. At half throttle the bike will cruise well on a flat surface but once I go downhill and speed up the engine seems to only perform so much. It feels limited if that makes sense. At WOT on flat it doesn't seem to have much of a difference. Also there is a semi rough noise coming from the engine. It sounds kind of grinding like but not a terrible grind. The engine makes the noise idling, and while riding.

Ill attach a video of me riding last night. (Excuse the clutch kill i have yet to wire my kill switch) I might sound dumb but here are my questions

Is this normal for break in?
Is there really that much of a performance boost after break in?
Am I Four Stroking?
Do I Need a new Jet?
Should I drain everything and try the standard 20:1 with 2 stroke oil?


Thanks in advance for all your help. I've learned a lot from this forum and i'm having a lot of fun! Im currently at work but I rode the bike here so if anyone has questions or wants pictures Ill try my best to help solve my problem!


Take clutch cover off see if 3 metal pegs on clutch pad cover are grinding a circle on inside cover.use double gasket around clutch cover to give um little more space.or grind um down just enough not to touch inside..or let it do it itself lol grind its own space after a while
 
Take clutch cover off see if 3 metal pegs on clutch pad cover are grinding a circle on inside cover.use double gasket around clutch cover to give um little more space.or grind um down just enough not to touch inside..or let it do it itself lol grind its own space after a while
Hi Jecameron91,
1st off, welcome to the forums.
For future reference, check the dates when something was posted when you answer a post.
The particular one your answering was last posted almost 4 years ago...lol...I have a feeling that whatever the problem, he either solved it or abandoned it altogether.
Again, Welcome to the forums and find the section here where you can introduce yourself to the other forum members, let us know your skill levels etc. as this info helps us to help you in future...DAMIEN

Ps...here is the link to the introduce yourself area of the forums...enjoy your stay with us.



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