Topic: Flippin' Petcocks

[ZombieBike]

Aright, so I bought a fuel tank on ebay to replace my junky tank and now I have 2 tanks and still no petcocks. The tank I bought is from a '76 CB550F and Bike Barn has universal petcocks and mounting plates. Anyone have any experience with these? What size mounting plate am I gonna need? I have also been looking on ebay. It seems the CB750 and the CB350 are much more common...as far as replacement petcocks go. Willl either of these work with either tank? I'm sorry if I am the needy newbie just asking a buncha questions and not contributing too much, but you gotta learn somewhere, right? Thanks ya'll...Kyle

[RDRF3]

   
   Why do you have 2 tanks and no petcocks ? Did yor tank not have one ?
   Do petcocks screw into tank or have 3 holes, 2 that are threaded ?
   What bike do you have . 
   Let me know I'll try to help.    Raymond

[ZombieBike]

sorry...I was sort of vague. I have 2 tanks and no petcocks because neither tank had petcocks (I am fixing the bike, I dragged it out of the woods at a friends house) My old tank, from the bike, is a 72 CB500F tank with 3 holes. The new one is a '76 CB550F tank. I have not recieved it yet (it is en route) so I don't know what kind of hole it will have in the bottom, I think it has 3 holes, if I remember corectly from the picture of it.. I will post more info when I recieve it. Kyle

[ZombieBike]

Aright, so I got the used fuel tank today. It is from a 1974 CB 550, and has 3 holes on the bottom, the two outside which are threaded for mounting. I measured the two mounting holes center to center, because that is how it said to measure in the "universal" mounting plate description on Old Bike Barn, and they are 22mm apart. The smallest "universal" mounting is 34 mm. Being a Yank, I am not really familiar with the metric system, but I know enough to know 34mm is much bigger than 22mm. I've searched eBay too, but am having no luck. Thanks ya'll...Kyle

[Terry in Australia]

G'Day Kyle, I'll go out to my garage and measure a CB750 fuel tap (petcock is so British!) 22mm sounds about right for a 750. Cheers, Terry.

[Terry in Australia]

I just went out and measured it, the distance between the two screw holes is about 18.5mm, or 24.5mm from one side of the screw holes to the other. I still think the older CB750/CB500 petcocks would have used the same tap. Cheers, Terry.