How to Maintain a Motorised Bicycle

crassius said:

dead gas is great for cleaning these things - when a bike comes in & I don't like the smell of the fuel or I can't tell the mix from the color, it goes into the dead gas tank and all motors get cleaned nicely before going out

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I have one of those as well, except it it's labeled with a huge ? in black felt pen.

You could probably douse a camp fire with it but it cleans grease OK.

1 to 2 minutes seems a bit long. Particularly if you're in Australia (correct?) and it's summer. If you're in the northern hemisphere, and it's winter, then I'd call that time 'not unreasonable'. Though still a bit long.

But assuming it's summer, then that doesn't sound right. But I'm anything but a fuel system expert. I understand the basic operation of a carburetor. But no details.

Could it be that you're running so rich that you're dampening the combustion?

And could a weak spark be so weak that it'll only support mild combustion?

I don't think this'll help much. But maybe it'll percolate some ideas.

it should be able to run right after starting unless it's Really cold outside like freezing or below. Mine starts, then I turn the choke off after about 5 seconds and it revs after about 15 seconds and that's at 40 degrees F here on a cold morning.
I won't ride it that cold without letting it warm up for at least 3 to 5 minutes, but it should be able to rev without stalling somewhere between 15 and 30 seconds after a cold start.
Check for vacuum leaks at the carb, manifold, and the base and cast gasket, you can use carb cleaner or propane to check for leaks as the engine will rev up a little when you get the propane or carb cleaner close to a leak.
Crank seals are notorious for air leaks when it's really cold too and those leaks will tend to seal up as the engine warms up, making them difficult to find in some cases.

If you're running 16:1 in it, then it's definitely too lean and will act even worse when cold.... You can add more gasoline to the mix and bring it up to 32:1... drain the tank back into the gas can and see how much is in there, then add about the same amount of gasoline to it to bring the mix up, even if you go 24:1 it'll be better by adding half the amount of fresh gas to the mix. This isn't gonna give you an exact 24 or 32:1, but it'll be close enough and the engine isn't gonna be mad because the mix came out to 23:1 or 25:1...

basically, if you got half a tank of 16:1 and fill it up with fresh gas it should be somewhere close to 32:1, best to drain and measure tho to be sure you don't top off 1/4 tank thinking it's 1/2 tank tho since it can look more full than it really is. This won't get you spot on with the ratio but it'll get ya close.

Lachiepower0402 said:

Just to clarify, what ever is in the tank, add that amount of fresh fuel to the tank which will bring it up to around 32:1.

Also I will be adding octane 98 fuel to the mix, where the fuel that is already mixed is not octane 98 but I think it is E10, but I am unsure. Would this be fine to do this?

Thank you in advance

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Ohh for heavens sake, go get a gallon can of good new gas and put 4oz of 2-stroke oil it, you can't be that broke.