Topic: K6 oil tank on a K2 hose routing

[kurtkarram]

Hello I have a 1971 cb750. I bought an oil tank for it on ebay, said 69-76. The tank is supposed to have 2 spigots: a small one to the back of the crankcase, and a larger one to atmosphere. The tank I was shipped looks like a k6 from what I read, as there is only 1 larger spigot at the bottom.

Will this work for my 1971? Do I connect this bottom spigot to the crankcase? What would be the best way to match the different size spigots if thats the case? I waited too long to get to this project, so I am unable to return it now.

[Shtonecb500]

the k1 tank should have a single spigot at he bottom and small diameter tube out of the back

[Old Scrambler]

Hard to tell what you have..............but it reads wrong. A picture would help Take a good look at the parts manual and the schematics available on this site.

[Old Scrambler]

Shtone...........................I've never seen a CB750 SOHC tank like that

[kurtkarram]

Here is the old and new tank. I had to buy a new one because I broke the threaded mount on the old one trying to take off the drain bolt so I can't reuse that.

[HondaMan]

The K6 had the vent hose's pipe coming out the bottom, next to the oil hose bung. Honda routed the vent hose from the top rear of the engine over the airbox, then down to near the tank, then joined this breather to that vent hose with a tee, then ran the hose all the way back to the right passenger footpeg where it was held to that bolt with a small bracket.

On the K1 the upper vent pipe from the tank (by that separator, which is the big round thing on the back-top of the tank) went to a shorter hose that went directly down to the chain area (New Factory design) or else just straight down to in between the swingarm and rear of the engine (Old Factory/K0 style) where it spit on the rear tire, if the engine was foaming the (incorrect detergent) oil(!).