carb blowing back

[baldyshinehead]

Z650, runs ok apart from one of the carbs blows back, a fine mist can be seen coming from the rear of the carb, sounds like a PFFFFFFFFFFFT every now and again.
Have changed the offending carb with no difference.

Anyone got any ideas please ?

[shaggy696969]

Inlet valve worn or sticking, compression check across the cylinders, you may need a grinding job.

[odie]

Could be out of sync

[baldyshinehead]

compresion test was fine.
timing maybe a little out but would that cause such a dramatic spit back on one carb only ?

[matthewmosse]

Did on my 500/4, had me baffled for a fair bit;)

[headless]

better watch that it don't catch fire if all that fuel stores in ur air box

most probably a sticky valve

[John Hopkins]

Don't ride it until the price of petrol goes down...John

[dracken1]

the amont of blowback needed to cause a fine mist would not always show up on a compression test

[teltwosheds]

pour a load of redex down inlet on comp, leave overnight and look down plug hole in morn, if oily take for good hard thrash:D

[Grav]

A Damn good thrashing?

Like this?

[trikerdrew]

Got a top end off a z650.Also bottem end less c/cases.

At the moment engine is comp sorta ie no starter,sprocket cover.

Got to recase gt motors with broke mountings.

Any good to you?

Drew

[nutbag1]

Z650, runs ok apart from one of the carbs blows back, a fine mist can be seen coming from the rear of the carb, sounds like a PFFFFFFFFFFFT every now and again.
Have changed the offending carb with no difference.

Anyone got any ideas please ?
try spraying a blast of easy start around the general area of the offending carbs manifold while the bikes ticking over, if your revs increase it points toward a crack or split in ya rubber manifold, good luck n let us know the outcome