URGENT!! Bike wont start after new head and piston

[50ccAgility]

Hi folks,

I have had a lot of bother with my Kymco Agility City 50, its always breaking down, however after a bit of time it will run again! Strange! I broke down the other day and lost compression on the bike
 I decided to strip the engine, the piston and rings were knackered and so was the gasket and the head. Got a kit and replaced all parts. I went to start the bike up and ITS GETTING FUEL AND A HEALTHY SPARK. He bike will turn over but will not fire up. Does anyone have any suggestions? Could the timeine be the problem? Does anyone knlw the markings for setting the crank? I found some brid instructions and lined it all up but doesnt seem t go! help please!!

Ally

[CROSSBOLT]

There should be a plug on the Machine right of the engine that will show the crank position which should equate to crank and piston top dead center. Then line up the cam so both valves are closed. There will be some kind of mark or marks on the cam sprocket that will show the exact position the cam should be when the piston is at top dead center. Fit the chain and tension it and you should be good to go.

Karl

PS: I have left a lot out of this like, "Loosen the cam chain by slacking off the tensioner," because you had to do this to replace all that you said. Also because there are some folks on this forum that are much more familiar with the bike than I am an may chime in with more info depending on what you do with the above info. This has a lot to do with the number of "URGENT, need help now" posts on this forum that are nearly the last we hear from the poster. He gets the info and is never heard from again.....

[50ccAgility]

Hi Karl,

Thanks for that, however once i set the timeing the bike still wont fire up. It has good compression, spark and fuel flow but it doesnt seem to want to fire up. Any input on this? What could iit be? Its turning over fast but wont start

ally

[245luigi]

Are you letting the carb bowl fill with fuel?

[50ccAgility]

Yeah its full every time, however the plug never seems to be wet when i take it out after tying to stsry it. Wonderig kf it something to do with the wire tht goes from the carb, possibly  automatic choke?

[245luigi]

You can find videos on youtube how to check the automatic choke. Starter fluid in the carb does nothing??

Is the kill switch on?

Seems like there is an issue between the carb and spark plug.

[SF11]

Yeah its full every time, however the plug never seems to be wet when i take it out after tying to stsry it. Wonderig kf it something to do with the wire tht goes from the carb, possibly  automatic choke?

If the plug isn't wet, that would suggest that fuel isn't getting in to the cylinder, so even though you are saying there is fuel at the carb, is the engine able to draw that fuel in. check for blocked jets, air intake leaks (you need to be creating vacuum to draw fuel through, even though you have good compression, does not necessarily equate with good vacuum at the intake).

Basically:

Compression
Spark
Fuel
(correct valve and ignition timing)

and it should kick into life.

[CROSSBOLT]

There is a little vacuum operated valve between the fuel tank and the carb. The seat has to come off and the helmet tub removed to access it. There will be three hoses attached. One from the tank, one to the carb to deliver fuel and one to the "manifold" for vacuum. First, pull the one from the tank to make sure fuel is getting to the valve. Put it back on if fuel flows freely thru it. Fix the blockage if it does not flow freely. Restore after fuel flows. Second, pull the hose off the carb that delivers fuel to the carb. Then pull the hose of the "manifold" that provides vacuum to the valve and suck on it ( it will taste terrible!). Fuel should flow freely out the tube to the carb. Replace the valve if it doesn't. The purpose of this valve is to turn off the fuel when the engine is not running. The toughest part is during starting especially if the float bowl is empty. Your "sucking test" will fill the float chamber if you suck long enough. These valves are notorious for sticking closed.

Take two aspirin and write us in the morning!

Karl

[blue]

There is a little vacuum operated valve between the fuel tank and the carb. The seat has to come off and the helmet tub removed to access it. There will be three hoses attached. One from the tank, one to the carb to deliver fuel and one to the "manifold" for vacuum. First, pull the one from the tank to make sure fuel is getting to the valve. Put it back on if fuel flows freely thru it. Fix the blockage if it does not flow freely. Restore after fuel flows. Second, pull the hose off the carb that delivers fuel to the carb. Then pull the hose of the "manifold" that provides vacuum to the valve and suck on it ( it will taste terrible!). Fuel should flow freely out the tube to the carb. Replace the valve if it doesn't. The purpose of this valve is to turn off the fuel when the engine is not running. The toughest part is during starting especially if the float bowl is empty. Your "sucking test" will fill the float chamber if you suck long enough. These valves are notorious for sticking closed.

Take two aspirin and write us in the morning!

Karl

x 2 then have a beer to wash the gas down.      LOL

[CROSSBOLT]

Here it is a week after Blue's input and not a peep....."URGENT" my foot!

Karl