Topic: CB750F petcock differences

[joe750]

I have come to another crossroads in my build.
I have a 76 CB750F that I'm working on and have a bit of a predicament on the tank
When i bought the bike i got an extra tank with it. Both F model tanks.
The extra one has the petcock on it but is full of rust pinholes.
The tank im using is perfect, sealed, and ready to go. But has no petcock.
When i went to swap it out thats when i realized they are different size threads.
Is it true the 75/76 F models had a different petcock than a 77/78?
And if they are, which one has the smaller thread?
Thanks!

[andrewk]

75/6 750F will have a 19mm petcock, 77/8 will have 18mm.

I haven't seen an aftermarket 19mm petcock, but you can still buy them from Honda, I just bought one for my F0 tank.

P/N is 16950-341-671, list price of about 80 bucks, but I think I got mine for about 60.

EDIT- just did a google search, aftermarket ones may exist? 

http://www.vintagecb750.com/products/6/fuel-system/67/fuel-petcocks-gas-tank-parts

Hope this helps!

[Tugboat]

You should be able to get 'em at cb750supply.com or z1 enterprises for like $40.. But yes, they are different. The F0/F1's exit vertically, while the F2/F3's exit horizontally to get over the PD carb manifold.

[joe750]

Thanks so much andrewk and Tugboat!
I'll get on that