queations

First I have 1980 kz 750 four cylinder I'm currently rebuilding the block...but when im finished the to black hoses on the valve cover this can be blocked off or just a single hose to both ports won't hurt anything right cause its a bobber don't have that stuff no more....the other is I have a new tank but has no petcock so I have all four ports on the carbs closed or capped it will run right with it like this or is their a alternative for a bobber.....thanks

"... I have a new tank but has no petcock..."

?? How will fuel get to the carbs? Ed

It has a gas valve u turn on and off but no petcock meaning has only one connection some bikes have two one that is use as a vacuum like to part on the carb with when given thottle the enigine vac will draw gas in to the bowl faster....I got the motorcycle with all the carb ports capped...I just want make sure with all the ports capped the gravity is gonna feed the carbs enough fuel under heavy rpms and or load

koloj wrote: ne vac will draIt has a gas valve u turn on and off but no petcock ...I got the motorcycle with all the carb ports capped....

Vacuum ports should be capped.

Vent ports should not be capped and should exit to open air.

Good Fortune!

The black hoses on the valve cover must be open to allow the engine to breathe. Consider connecting both to a T, then putting a small valve cover breather filter on it.

Okay thanks much

koolaid_kid wrote: The black hoses on the valve cover must be open to allow the engine to breathe. Consider connecting both to a T, then putting a small valve cover breather filter on it.

You do not have to keep those open, they are not the crankcase vents but part of the smog system.
The breather is on top of hte engine block behind the cam chain tesnioner. You can simply tie both ports on the valve covers together using a piece of hose.

What Baldy said,


like this
Pete

I stand corrected.