So i'm new to motorbiking. i bought an engine off line because i thought it would be a good idea. i started putting it together yesterday and ive had nothing but problems since. just one thing after another. my problem now is when in open the valve on the gastank the carb just starts pissing gas everywhere. please help! grubee skyhawk 48cc
http://motorbicycling.com/f4/motorized-bicycle-carburetor-pictures-how-install-195.html
This is good to read will get you familiar. Float adjustment to low or you have small debris in the needle valve.
Of course take a breath a look it over if'n your fuel line connections are not up to par leaking.
This is good to read will get you familiar. Float adjustment to low or you have small debris in the needle valve.
Of course take a breath a look it over if'n your fuel line connections are not up to par leaking.
could be a bad float, or it might just be stuck. if you take the float bowl off the carb (the two little phillips screws if it's an NT) the float is the little plastic donut thing. if it's got fuel inside of it, it's got a hairline crack somewhere and it's filling up with fuel and not "floating."
the only cure is to replace it.
let us know what you find and we'll go from there...
the only cure is to replace it.
let us know what you find and we'll go from there...
It was a good idea! It is tiring but you'll narrow it down and figure it out. I can relate....frustrating!
I concur with goat herder... it's probably just a small speck of dirt in the float needle thats causing it to flood like that.
The Float meters when to shut off the fuel. It sits on a tang that can be gently [bent] adjusted to proper placement.
The float lets fuel in the bowl so the motor can have some Vy a venturi metering rod type set up. A healthy motor will draw in air and take a sip of fuel that gets atomized with air coming in.
While I am not familiar with this carb yet. Looks to me the part on the bottom of the float bowl is a fuel bowl drain for when one puts the bike away for a long period of storage they drain the bowl and tank out at the same time.
The other brass tube on top is for a vent. Simply put it lets the bowl vent air out and in as the float corrects the float bowl fuel level.
The carb has two adjustment screws on it one does idle the other does fuel air mixture.
Somebody more familiar with this carb will pipe in shorty . Hang in there.
The float lets fuel in the bowl so the motor can have some Vy a venturi metering rod type set up. A healthy motor will draw in air and take a sip of fuel that gets atomized with air coming in.
While I am not familiar with this carb yet. Looks to me the part on the bottom of the float bowl is a fuel bowl drain for when one puts the bike away for a long period of storage they drain the bowl and tank out at the same time.
The other brass tube on top is for a vent. Simply put it lets the bowl vent air out and in as the float corrects the float bowl fuel level.
The carb has two adjustment screws on it one does idle the other does fuel air mixture.
Somebody more familiar with this carb will pipe in shorty . Hang in there.
I'm not being sarcastic here but is the carburetor installed correctly? Don't laugh. It has come up several times from new comers who have installed the carb upside down as per the photos that come with some instructions. The fuel inlet on the carburetor must face up. Sorry if that sounds elemenatry but as I said; it has happened and not that uncommon. Absolutely no offence intended, sir.
Tom
Tom
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i found the answer to my problem. so there was a little bit of debris on the inside. i cleaned it with carburetor cleaner. also i dont know if it made a difference but the carburetor wasnt completely right side up. so that could of been the problem too. i got it to turn over a for like 2 seconds today then my chain popped off and it died. so now i can't get my chain to stay on. any ideas?
Make the rear sprocket is perfectly straight no wobbling. You tighten the hardware there evenly in a star pattern. If it is not even loosen it up or then give it a gentle pat while tightening . The Idea here is have a wobble free sprocket.
If you are using the kit supplied teinsoner sometimes those need to be custom bent to go in line with the chain.
If your sprocket has a offset to the teeth point that to the out side it will help clear your rear tire better.
If you are using the kit supplied teinsoner sometimes those need to be custom bent to go in line with the chain.
If your sprocket has a offset to the teeth point that to the out side it will help clear your rear tire better.
Im new to motorized bicycles 2. I have the same problem with my sprocket. I know how 2 fix it now but the only problem is that the 6 of the 9 bolts that it came with broke in half. I highly recommend you buy some new bolts. The ones that the kit comes with are crap and are probably bound to break later on. Judging by the carb, you have a grubee skyhawk engine kit just like me (I have the 66cc engine). Tomorrow I'm going to home depot and buying some new bolts and hopefully my bike will be running. Hope your bike works out for you and the sprocket isn't as much of a pain for you as it was for me.
What's wrong with your sprocket? Why replace it? As for chain many of us recommend switching to a good industrial quality #41 chain. Usually available at Ace Hardware, Grainer, Tractor Supply and other industrial supply places. It usually comes in 10 foot lengths. Those places mentioned also have master and half links. Good luck.
As for breaking the sprocket bolts; ease up on your wrench/socket. Properly torqued they should not fail. Same for all engine and mounting fasteners. If you must replace them stay away from stainless steel fasteners and go with no less than grade 5 steel. Watch the quality of Home Depot fasteners. They come from the same place the ones that came with your kit did.
Tom
As for breaking the sprocket bolts; ease up on your wrench/socket. Properly torqued they should not fail. Same for all engine and mounting fasteners. If you must replace them stay away from stainless steel fasteners and go with no less than grade 5 steel. Watch the quality of Home Depot fasteners. They come from the same place the ones that came with your kit did.
Tom
