Topic: Supersport tank interchange

[legendary]

Hey Guys,
              I just bought a 1976 CB750 Supersport. The bike was a great buy.... because at some point it was vandalized.

The tank, headlight, signal lights etc. were pounded in with a hammer.  Everything has been pretty easy to locate except the tank.

Can someone tell me what other year tanks will fit this bike??

Appreciate the help.

Steve

[scondon]

75-76 750f supersort tank is a direct replacement. 77-78 750f is the same size and dimension but uses a different size, single outlet petcock. A "T" or "Y" fitting can be used to split the single fuel line to the two fuel inlets on your '76 carbs.

   Other cb750 tanks should fit on the frame fine, but will leave a large gap between tank and SS seat.

[750essess]

both my 75 and 76 ss tanks have single out put petcocks??? is that unusual?

[russouno]

I have a K frame and tank with an F seat.  There was about a 1in gap between the two...personally I don't think it was that much of a deal.

[gregk]

I am in the process of replacing my 76 SS tank with a 77 SS tank.  You are right, the petcocks are different.  I just came back from the wreckers with a petcock off on of those Honda 500? twins where the heads stick out the side like A Guzzi.  That petcock fits the 77 tank and has a single outlet. 
The 76 has a single outlet tap.  Don't know what the oem tap on the 77 looks like. 
Here we go again with another paint job!

Greg

[paulages]

I am in the process of replacing my 76 SS tank with a 77 SS tank.  You are right, the petcocks are different.  I just came back from the wreckers with a petcock off on of those Honda 500? twins where the heads stick out the side like A Guzzi.  That petcock fits the 77 tank and has a single outlet. 
The 76 has a single outlet tap.  Don't know what the oem tap on the 77 looks like. 
Here we go again with another paint job!

Greg

that would be a cx500. the standard petcock might work, but the cx500 "custom" has a different style.

[scondon]

both my 75 and 76 ss tanks have single out put petcocks??? is that unusual?

The 76 has a single outlet tap.  Don't know what the oem tap on the 77 looks like. 
Here we go again with another paint job!

Greg

   It's been 6 months since I looked closely at the '76 rusting in my drive. I was going on what I "thought" I remembered about the petcock. Thanks for catching that guys

Good news about the cx500 petcock fitting the 77-78 Supersport tank, Greg/paulages. Is it a direct replacement? Meaning, are any mods necessary in order to fit/route the fuel line to stock carbs?

[gregk]

Looks like the gas line may interfere with the choke operation on the 76.  I haven't got the 77 tank on the bike yet.  I will probably need a longer piece of gas line to make the connection.  Otherwise I will run the line on the outside of the left most carb.

Greg

[legendary]

Guys,
         great info. I appreciate it a lot.  Pet cock on my tank is undamaged... it has one outlet.

A lot easier to look at a four year range than '76 or nothing!!

[.RJ]

I have a K frame and tank with an F seat.  There was about a 1in gap between the two...personally I don't think it was that much of a deal.

How much longer is the Supersport/CB750F tank than the K tank?

[.RJ]

^ Bump 

[cafe750]

Looks like the gas line may interfere with the choke operation on the 76.  I haven't got the 77 tank on the bike yet.  I will probably need a longer piece of gas line to make the connection.  Otherwise I will run the line on the outside of the left most carb.

Greg

I put a 78F tank on my 75, and I found that the fittings where the petcocks attach are different sizes. The 78 petcock has an outlet on the side, and if you run a fuel line straight to it, it'll get in the way of the choke linkages. I loosened the petcock from the tank, and rotated it 45 degrees, so that the outlet points more towards the carbs, and the line went right on. Hope this helps!

[dustyc]

RJ, here are some pics and measurements.  K tank from the back side of the cup to the end of the tab that fits the rubber mount is 19-1/4".  The F tank measures about 19-1/2", so that shouldn't be a problem.  The overall size of the tank is where the problem comes in as you can see in the pics.  The F is about 2-1/2" inches longer.










Back to the regularly scheduled program.

[.RJ]

The F is about 2-1/2" inches longer.

Excellent, thanks   Now to see if I can make this work...