Won't idle and loss of power.

T

theblueboy

New Member
Hey everybody!
I bought a 2 stroke 80cc engine and I have rode it for about 67
miles and changed the gas ratio from 16:1 to 20:1 after 25 miles.
And I've been riding it lately at 27 miles per hour on flat and recently
installed the fuel filter. The next day I put in some 5 month old gas
and it seemed to run fine for about 10 min until a bunch of white smoke
shot out the bottom of the muffler and it would hardly run. I tried to
start it several times but nothing happened. I drained out the gas
and bought some new gas the next day. I mixed it 20:1 and filled up
the tank and it took a few tries to get it going and it ran just fine but
when I tried to idle, it dies instantly. And it doesn't go as fast as before.
I could get up a hill at 19mph and now it goes up a hill at 14 to 15mph.
My brother says that it could be the throttle cable because, it feels very loose
and it twist forward with out any effect to the cable. Should I shorten it?
Or could it be something wrong in the carburetor? Somebody, if you know what's
wrong please tell me asap!

:-||
 
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Use the adjuster at the top of the carb to take up most of the slack, then do a final adjustment at the throttle twist grip.

Take your plug out and have a look at it....it should be brown to black, not grey or white. I would also clean the float bowl, and the jet, and make sure it's screwed in all the way.
 
sounds like your plug is a bit fouled from whatever you put in there, or something is clogged up in the carb. give the carb the once over and make sure its not gunked up and also check you plug as nougat said
 
Nougat said:
Also, 20:1 is pretty oily. 32:1 at least. I'm not sure what you mean by "5 month old smoke," but if you put five month old premixed 2-cycle fuel into it, that's going to be a problem. Gasoline goes stale over time, and gasoline with 2-cycle oil mixed into it goes stale in about a month.
Click to expand...

I actually mixed the five month old gas right before I used it
so it wasn't the oil that was five months old it was just the gas.
Sorry about the mess up on "5 month old smoke". I mixed up smoke and gas.
Whoops!
 
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Check the exaust. I had the same problem with my old 48cc motor.Soak it with your
favorite degreaser.The catalectic conveter gets cloged with oil 16 or 20-1 is
enough to do it.
 
check the cap on top of the carb...if that loosens up you wont idle right and youll start 4 stroking at your high end
 
noco said:
check the cap on top of the carb...if that loosens up you wont idle right and youll start 4 stroking at your high end
Click to expand...

Do you mean the part where the throttle screws in or the big
black thing with 4 tubes hanging out? And guys, a quick update
on what I've done. I took off the muffler and cleaned out the baffle
and took the bike out for a spin without it on and it went faster but
it sounded like when I twisted the throttle grip to a certain part
it started 4 stroking at about 20 mph and so I put the muffler back on.
I haven't tried it yet with the muffler back on but I will and see if it still
4 strokes. I also cleaned out the carb and everything that was in it.
After every thing I tried it still won't idle. But I don't know what you mean,
what part of the carb do I tighten?

zpt
 
Hey Guys!
I took it out today and unscrewed that screw on top of
the throttle cable connected to the carb almost all the way out and it idles!
I was wondering if you guys know what sprocket should I get to make it go
faster? I have a 44th at the moment and get around 25-28 but should I get a 33th?
Thanks guys for all the help!

.shft.

dance1
 
32 or 36 tooth. if you have any hills, 36, but otherwise 32 will do.. anything less than that and these motors just won't pull
 
youre pretty light so ~36t would prob get you well into the 30's without much bottom end bogging. i think pirate, dax, and CE all have 36t sprockets for sale.
 
I found one on eBay for $25 free shipping.
I asked the guy what it could be used for and he said
home made bike motors. I wanted to be sure that it wasn't
some cheap thing that will break. But I did some researching
and people said that if you get a smaller sprocket and run it a
full speed it will make the motor spin to fast or something and
about rpms? I'm only 15 so I really don't know these thing that well.
Also, how else can I make it go faster besides a sprocket? Some people said that
getting a moded muffler would help. I'm just tryng to see if I
can get my motor up to 35 or 40. The other thing is I haven't broken I'm my motor yet? Does anbody know how long it will take and how fast I will get when I do? I've done about
50 miles so far. I'm also currently using 25:1 in oil mixture.

xct2
 
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Go to a 36:1 or 40:1 MIX.
A smaller sprocket will LOWER your cruise rpm.
You aren't ever going to go faster than 35 or 40, so don't waste your time or money trying. When you turn 16 get a motorcycle if you want to go fast, and live to tell about it. (maybe)
 
Bikeguy Joe said:
Go to a 36:1 or 40:1 MIX.
A smaller sprocket will LOWER your cruise rpm.
You aren't ever going to go faster than 35 or 40, so don't waste your time or money trying. When you turn 16 get a motorcycle if you want to go fast, and live to tell about it. (maybe)
Click to expand...

Okay. So whats the fastest do you think I'll ever go on flat?
I did ask some other people ad they said that I should give my motor sometime
to break in. Here's the original post ~ http://motorbicycling.com/f3/muffler-12168-2.html
Just read page 2. I'm not saying that I don't believe you, it's just I want to be sure.
I see that you have a lot of posts and experience, so I know you know what your talking about.
Just give me an update on what you know.
Thanks!

Andrew
 
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