wont start

[duggy191]

Hi i suffered a throttle cable snap just as i was leaving college last thursday, the cable snapped at the carb end right at the connection and subsequently had to take the whole rack off to get to it with pliers. new cable attached carbs back in everything re attached only problem is now it wont start. im 99% sure everythings back in the right place its got a good 1/2 a tank of fuel back in and the taps on no kinks in the pipes nothing doesnt sound like it wants to fire last weekend i checked the plugs to find there were near enough dead and have some arriving tomorrow but have ridden it fine between then and the throttle snap, any ideas what could be the cause was extra careful with the carbs, will try again tomorrow afternoon with new plugs.

cheers

George

[Variablevalves suck]

Hi George,
You need to back over the carbs as you must have missed somthing having taken them off, have you connected the vacuum pipe up correctly.

[duggy191]

well i didnt disconect anything from the carbs only from the fuel tank air box all piped were left on at the carb end only the choke cable came off that end, il have another look later as im fitting the new plugs.

thanks

[duggy191]

had a slight breakthrough when taking tank off and disconecting fuel lines, i noticed the line were dry and nothing would come out the tank. the fuel tap its self is snapped so you can only turn it but no matter where i turned it or left it no fuel would come out the fuel line nozzles i checked the filter seemed ok and could blow through the fuel line nozzles, however i poured some fuel through the fuel lines because the carbs were empty once carb ress's were full and lines filled with fuel i tried to start it but nothing again no firing not even a splutter, will the carbs need a complete system connected in order to pull fuel through? really confused to what the problem could be.

thanks for any help

George

[greywolfhunter]

this could very well be a problem with the vaccume pipe-diaphragm, you should get you're self a piece of spare tubing and suck on it (gay, i know) when its disconnected from the bike (main fuel line) and see if you can coax some fuel through it, if not and you do have fuel in the tank, try on reserve, another suck. if no success, drain the tank by syphoning, (again, sucking on a tube and letting it leak), dismantle the fuel tap and see if the diaphragm system is shot.

if not, just replace the whole tank tap. hope this helps -

Mat

[duggy191]

I will try this, just dont understand how its gone since the throttle snap before it was working fine but when i replaced the cable and put everything back together wont get any fuel through anyway will stick at it.

cheers

[Variablevalves suck]

If you remove the small screw that holds the plate on to the front of the fuel tap you can turn the tap another 1/4 turn and get 'prime' this will allow fuel to flow all the time as normally it will only flow when the vacuum pipe is connected and the motor is spinning.

[duggy191]

Right, got the bike to start the problem now is it wont stop revving. sometimes it throbs on and off every second until revving out the the max with no way of stopping it. the throttle cable is not to tight and shuts off fully, on the bottom of the gk76a carbs there is a little screw tap thing, what is this? and any ideas why its constantly revving out.

thanks again

George

[greywolfhunter]

it could be the idle adjust screw that's too loose (tighten to decrease)

you should also check that the carburettors internal springs that open and release the throttle are okay and that the 'pistons' inside the carburettor (the big metal cylinders that the needle is in) all go up and down well and smooth

that's all i can really say. hope it helps

[Variablevalves suck]

Are you saying when it starts on the choke or when warmed you?