Topic: Calling all 1978 CB750K's

[26.2]

Hello all,

I’m asking a favor from all the owners of 1978 CB750K.  Please have a look behind the sprocket on your rear wheel.  Does the FLANGE (the part which the sprocket bolts to) look like the “picture 1” (from the parts book), or look like the “picture 2” (the part from my bike)?

The difference between the FLANGES is as follows:

“Picture 1” - From the parts book (and all the examples I’ve see on eBay) have the buttresses on either side of the Stud holes,

“Picture 2” - From my bike, there are no buttresses, but the Stud holes have more metal surrounding them

I know that the rear wheel on the 78 CB750K was different (17 inch rim vs. 18 inch on earlier models).  I don’t know if the FLANGE on my bike was a change in design, or was the wrong part put on the previous owner.  I’d like to find out what is on other 78 CB750K since the parts on my bike failed (the stud bolts sheered off, damaged threads in flange).

I’m in the process of trying to locate another FLANGE and want to assure the proper part and fit.

Thanks in advance,
- Tom

[Lumbee]

...mine looks like #2...

[frostypuck]

Mine looks like picture #2, also, and the parts diagram I just looked up also looks like #2 for the '78.
Chris in Boston

[Buffo]

Buffo's pile looks like #2

[blackhog02]

mine looks like number 2

[26.2]

Thanks fellow CB750 K8 riders,

Through your input, I was able to get the proper part number for the 1978 version of the FLANGE.  For your records it is part # 42610-405-000

... and NOT part #42609-341-000 which I was going to order and is the Flange for the earlier bikes.

Thanks again,
- Tom