Mad4lyf

Its sounds pretty clear that the problems centre around air flow. Make a list of all possible air issues an check them - eg air filters?

Your carb works on a venturi - the faster the airflow, the larger the vacuum it creates, the more fuel it sucks out into the airstream through a fuel conduit.
If you dont have enough airflow through your carb, it does not create enough of a vacuum in the venturi to suck sufficent fuel out of the carb.
So either there is not enough airflow (the airflow is blocked), or the fuel conduit (or jet) is blocked, and therefore requires increased vaccum and airflow to overcome the increased friction in the conduit.
Have you cleaned the idle jets/conduit to the jets?

I had a similar maddening problem with my VFR, eventually traced to a fuel line which kinked but only when the tank was bolted down, not when it was put in place.... hilarious.... not.

so check your fuel tap, fuel line, and also next time it does it, undo the petrol cap: if it suddenly picks up, the vent in the cap is blocked, meaning petrol gets sucked out of the gas tank, but air can't get in to replace that, creating a partial vacuum which stops fuel flow eventually. Also hilarious.

do stuff like take the fuel tank off, run it with an independent tank, check vacuum lines (does your petrol tap have a diaphram that stops fuel flow? you might have to run it in PRIME position).

have fun, theres nothing more hilarious than an intermittent fault.

Have a real, real good look at the hoses under the tank. There's a very good chance that you're either kinking one of them or trapping it between the tank and the frame.
Normal culprit is the tank vent hose, but check em!

Originally Posted by kinger

Have a real, real good look at the hoses under the tank. There's a very good chance that you're either kinking one of them or trapping it between the tank and the frame.
Normal culprit is the tank vent hose, but check em!

Thanks guys but the jets have been cleaned and all the hoses checked iv also opened the lid on the tank and still get the same problem im going to try run it with an independent tank and see what happens

Originally Posted by R-Soul

Its sounds pretty clear that the problems centre around air flow. Make a list of all possible air issues an check them - eg air filters?

Your carb works on a venturi - the faster the airflow, the larger the vacuum it creates, the more fuel it sucks out into the airstream through a fuel conduit.
If you dont have enough airflow through your carb, it does not create enough of a vacuum in the venturi to suck sufficent fuel out of the carb.
So either there is not enough airflow (the airflow is blocked), or the fuel conduit (or jet) is blocked, and therefore requires increased vaccum and airflow to overcome the increased friction in the conduit.
Have you cleaned the idle jets/conduit to the jets?

We have tried and check just about everything besides the cdi we have removed the air box and replaced it with individual filters but as soon as you put a load on the bike the problem comes back my mechanic says it must be an electrical fault and i nw need to source a gj73a cdi

Also check that the rubber mounts for the tank are in place as they can allow the tank to sit lower than it should if they are missing. Electrical sounds a stretch to me as you are able to get down the road aways before it ceases so I would go for a restriction somewhere or a pinch in the lines or cables. Try with the tank sitting up on a sponge and bungeed into place.

Cheers