not firing on all cylinders
 

ok, heres a conundrum for you tech heads,
got a f2 600, refuses to fire on cylinders 1&2.
ive plug swapped from 3&4 cylinders so its not the plugs
triple checked coils and wiring all correct,got sparks on all 4 cylinders.
carbs stripped and cleaned all present and correct.
got fuel in tank and carbs.cylinders getting fuel.
battery is new and fully charged.
only thing is cylinder 2 seems to be chucking fuel back through the carb.
any help would be gratefully recieved.:icon_toast:

You don't have 1 and 2 on the same coil, do you?
Spitting that much gas, the plugs can't be good. I'd be looking into the carbs on that.

Definately going to strip them again. and no. left coil going to 2&3, right coil 1&4.

Assuming engine compression is good it sounds like possibly a problem with the carbs or the sync might be way off, but the sync doesn't really explain the excess fuel problem. If you tear the carbs apart again double check the float levels and make sure they are correct. If they aren't set right the bowls will continue to fill with fuel after they're full and dump a bunch of excess fuel everywhere..

Just thought a bit of history on the bike might help with diagnosis. Was it running ok before the problem or is it a bike you are trying to get running? That might help eliminate some fundamental problems like compression/head gasket issues.

When you say it's chucking fuel back through the carb, what exactly are you seeing?

Just to clarify, bike was. running on 2 cyls when i got it. drained all fluids, no oil in water and vice versa.the bike was started by using batt booster without a batt fitted.also with carbs off all ports lookclean apart from 2nd pot which is black,this is also the carb which is spitting fuel. hope this helps

Bump

Does the F2 have a vacuum operated fuel tap like the 1000f ?

Is the vac line running from cylinder 2 ? - yes - then fuel tap diaphagm has split.

has the bike been stored for a while? could be that a bit of fuel has congealed in the carbs - this has happened to a couple of my mates who have old type carbed r6's after storing them over the winter. Engine doesn't fire properly and fuel goes everywhere. I think both of them just got the carbs cleaned and set up to cure it. good luck