Topic: CB750K twin disc conversion... HELP!

[Bwana]

I've got a '78 CB750K I purchased years ago on the cheap as a parts bike for the one I've had for ages.   It's been sitting untouched missing very few parts for 11 years and has been begging for revival.   I'm planning on a complete teardown of the entire bike & will also slap a chair on it, so I am really wanting a bit more stopping power.  Hence the question. 

I located the tip here for the job and have run into a bit of a snag.

I can't seem to find the 500/550 part needed for the switch.    In particular "CB500/550 speedo drive plate (no modification)."   Looking at a few parts fiches the drive plate appears to be identical to the one on the 750 (part
44641-375-000 - see part 6 front wheel.

Does anyone know what 500/550 the tech tip was referencing as a source for the part?   It must have an outer diameter that just fits inside the rotor.   The ones on the bike are  too big to fit. 

Better yet, does anyone know the actual part number?

Even better, does anyone know of a source that actually has the part in stock?

More betterest, does anyone have one sitting around they'd be willing to part with? 

Thanks in advance.

[MCRider]

The part about the speedo drive is wrong. I had a discussion with the author and he agreed. It has never been changed.

You have to modiy the 750 drive plate. You can caveman it as I have done, by grinding down the OD of the stock plate leaving enough material to bend over as tabs to fit against the flats of the hub. Or...

You can have one made, as i have done also. Cost $20. I'll find some pictures, they are all over the forums if you search. Otherwise, someone else will post them or I'll find mine later.

Don't be deterred its obviously very doable as many have.

[Bwana]

I'll find some pictures, they are all over the forums if you search. Otherwise, someone else will post them or I'll find mine later.

Thanks...

http://forums.sohc4.net/index.php?topic=37258.0

[MCRider]

There are the pictures of what you need in that thread. About 1/2 way down and mine about 3/4 way down page 1.