Miss fires if running in traffic

[Whomightyoube]

Thanks for your reply.


I was just wondering if the symptoms on their own are indicative of a basic problem. I have done some investigations of my own.


I have historically not had to use choke much at all on this bike but I I try to start with no choke now the cylinder 3 does not fire at all. It starts smoothly on choke and runs fast. I put the choke in pretty quickly after starting off.


I know it is cylinder 3 as the down pipe is colder or completely cold if I start with no choke. Have got new plugs. Sparks seem good. Swapped coils etc, always cylinder 3. Swapped over the two leads which fire at the same time. Re prepared the lead ends.


I have cleaned carbs thoroughly including transfer lines and replaced bits on carb 3.Basic kit with new O rings gasket and float valve. Float in good condition.


I have done compression test and cylinder 3 is down but still over 100 psi. I am thinking that it may be valve clearances or sticking valve? Would this cause this intermittent fault?


When I run out on an open road all down pipes are the same temperature and it runs smoothly even at low revs.