Petcock question

[PrimePerformance]

I noticed the other day that my petcock was leaking and has been making my bike kinda hard to start lately i noticed its a vacume type petcock is it possible to switch it over to the non vacume petcock because i have one laying around from a xs650 tank that dont have a vacume any idea if the non vacume one will work off it?

 

[frwinks]

if it bolts up then it'll work. The bolt spacing is 46mm OC on our tanks, I've been running a non vac petcock all season

 

[Snoman6115]

the vac on the 400 was only to turn it on and off as the motor was running. like frwinks said, if it fits go ahead, just remember to cap off the carb boot when you remove the vac line or your engine will not run. mine pops off occasionaly and engine jsut dies

 

[PrimePerformance]

Thanks for thehelp guys ill have to try it out after dinner and see how it goes

 

[Old Okie]

Hope you got your petcock to work, I am still struggling with mine. MikesXS has non vacuum petcocks that fit our bikes but they are out of stock at this time. I saw a fitting that converts our petcock mounting spot to a standard type petcock using a 2 hole mount and then putting a standard petcock that screws into that mount. Does anyone know where that conversion kit can be found??? I was told, by a Yamaha dealer, that there was a recall on some of our petcocks, the cut-off valve was faulty. The repair kits for the petcock will not fit on the recalled petcock. I have the recalled model. The kit will not work on it. I seem to be stuck in a situation and no way out for the time being.

 

[Lou Ranger]

Wow, talk about a chicken-or-egg runaround. At this point I think I would be visiting a bike graveyard or wrecker to get a used unit off either a 400 or 650 so I could keep on the road at least. Good luck.

 

[Old Okie]

I have other running bikes so I am not missing any riding time. I have a Honda CX500 Custom and a CX500 Turbo, the Yamaha XS400 belongs to a friend, I am trying to get it back on the road and he is in no hurry to ride.

Got tired of working with the old vacuum petcock so I ordered an adapter plate and a standard petcock from partsnmore, about $45.00. Should be here in 3/4 days. There was a recall of the petcocks on some of these '78 XS400s, My bike has the recalled unit and no kit is available for it.