Topic: 82F gas tank on 78K

[sinnergsx]

Hey all, I have a 78 tank that has seen its last day.

I'm looking for slightly thinner tank to straddle.
I know the 76-78 F tanks will fit lengthwise, but was sure about the early 80s F tanks. They look the same to me and I can find 80s tanks more than I can find 70s tanks.

Bikes a cafe style with a custom seat, and I can weld and fab just fine so no issue there, but I wasn't sure about the tunnel and front mounts.

If they're all off, I wouldn't bother.

-Cameron

[seanbarney41]

The post 79 dohc F tank was designed to cosmetically join up with the sidecovers...so there is that.  Probably the main reason no one really ever tries to use them on other bikes.

[sinnergsx]

Yeah I've noticed they kinda sweep down and have the dog ears for the side covers. Could look odd. Wish I had one just sitting around to look at.

The sohc F tanks don't have this? For some reason I thought they did. Maybe I'm just not familiar with which year tanks look like what.

Anyone got a pic of a sohc F tank? Feel like they're fricking unicorns.

[newday777]

The SOHC F tank does not go down

[sinnergsx]

Oh yeah that's what I need. Too bad I'll probably never find one 😆

That one there is pretty though.

[newday777]

Yah it's a bit better than the one I have

[seanbarney41]

I just bought a really nicely re-painted 77f one for about $450,which would be ok except the repro stripe kit that was applied is very  incorrect...oh well.  It still looks pretty good.  It took a couple months to find it and more than I wanted to pay for not original, but they are out there if you are willing to cough up.  And then the most ridiculous part is nice, original, complete 75-78f is tough to sell for more than about $2500.

[scottly]

I wonder why the F tanks rust so bad?

[seanbarney41]

I wonder why the F tanks rust so bad?

It truly seems like Honda truly got hold of a batch of inferior steel or perhaps something with how the seams are welded?  A question I have never found a convincing answer to...

[scottly]

Once upon a time, gas tanks were made from lead-plated steel, called terne, which protected the steel from rusting. Alcohol can dissolve lead over time, but some of the F tanks look to have been rotted out well before 10% alcohol became the norm, and K tanks seem to have a much better survival rate?

[kerryb]

This tank came in a pile of parts.  I don’t know what it’s from, but looks similar to what you’re asking for.  I can take some measurements if you like.

[newday777]

This tank came in a pile of parts.  I don’t know what it’s from, but looks similar to what you’re asking for.  I can take some measurements if you like.

Suzuki tank possibly??

[kerryb]

I was leaning towards early cb650.

[Laids]

I used a Suzuki 450 tank, 80’s. The front fit perfectly, welded an attachment to the frame at the rear. Not as much capacity but changed the look of the bike.

[Dime]

Depending how bad your tank is there is a process called renew. I had a 1980 cb750c and the tank, on stipped, was found to be patched with fiberglass. The guys brazed new pieces in and did the renew process which gives the tank a whole new liner. It means the exterior of the tank being stripped of paint but you are left with basically a brand new tank. Think it cost me about $150. Don't know if you have something like that where you are or if.it is an option