Engine Trouble 66cc GRUBEE NEEDS HELP

[cigron]

GT2 bike 66cc. Im having A problem.It runs good every once in A while when running
about at ¾ throttle it act like it`s running out of gas.I have A clear plastic gas line
and I can see that it`s got gas if I slow down to 10 to 15 mph it will run ok.It`s not
broke in yet so Im running gas and oil at 18 to1 after im going to use amsoil 50 to 1.



Some times the complexities of simplicity can be overwhelming. It`a A two stroke thing

 

[jsw5620]

Check out my post below and see if it may be your problem.

http://motoredbikes.com/showthread.php?t=25747

 

[cigron]

That was the first thing I checked the needle was in the second slot.
I had that problem with A SR500 yamaha.I took the air filter off
and stuck my finger in it.It was just fine.I was wondering if my
18 to 1 gas & oil mix is to mutch that junk spark plug that came
with it. I went to NAPA and ordered some new plugs NGK6HS
they should be in tomorrow. I hope that does the trick.

 

[jsw5620]

The problem with mine was that the needle valve and main jet was loose and laying in the bottom of the carb.

 

[AussieSteve]

cigron, the fuel/oil mix won't be your problem. I ran mine for 400km at 16:1 without problems. The plug was a nice tan colour, no burnt oil residues.
Running at 20:1 now.

How does it run at wide-open-throttle, (WOT)?

If it only misses in mid-throttle openings, up to ¾, try dropping the slide needle to it's lowest, (leanest), setting, (top notch).
Otherwise, your main jet might be too big.

Does the missing sound like 4-stroking?
(If you're not sure about 4-stroking, see 'NT Carb Tuning Basics', there's a link to a really good video illustrating it. Worth a look.)

Glad you're gettting a B6HS, the stock plugs aren't worth a pinch of s@&#.

 

[cigron]

It ran good wot then every once and A while it would not run over half
throttle.then I would slow down for A while then it would run wot
for A while. Im going to put A new spark plug in it and go from their

 

[jsw5620]

Not sure that I'd be running it at WOT since you haven't broke it in yet.

 

[AussieSteve]

WOT doesn't mean 'flat-out revs'.
The throttle can be fully open from idle, under load.

 

[jsw5620]

I guess I need to get that mentality out of my head that WOT is high revs LOL. I was just going of the break in procedure that came with mine that said keep RPMs low during the break in.

 

[cigron]

Thanks for any inffo. when I had it at full throttle. I was not
going as fast could.At about 20 mph Iwould let up on it.It feels like
it will probable go about 30 mph It runs good most of the time.
every once in A while it feels like it`s not geting enough gas
but I have A clear gas line snd I can see the gas in it.