Topic: 750K vs 750F Frame

[cadenpearson]

Hello!

I have a 1978 750F. Dug it out of barn last summer with no title / no bill of sale. Planning a cafe build, but first things first I want to get it legal. Someone across town is selling a '78 750K frame & motor with a clean title for $300. I'm curious about the differences between F and K frames. I've read that the fork angle is slightly different. I know the swingarms are different due to the disc brake, but is there any reason why an F swingarm would not fit on a K frame? Different pivot bolt size or anything?

I'm looked all over for frame specs / plans but haven't found much. Any help is greatly appreciated!

Thanks!

[754]

Kickstand length and mount are different,  maybe a welded on bracket for wiring up by the neck.  , I think two bungs welded on the  neck area.  . Swingarm pivot on frame should be the same, but F pivot bolt is longer, to allow the cast footage brackets.

[cadenpearson]

Perfect! Thanks for info. Would I be able to use the F swingarm on the K frame if I used the K pivot bolt?

[70CB750]

Perfect! Thanks for info. Would I be able to use the F swingarm on the K frame if I used the K pivot bolt?

If the K has disc brake you should be able to. 

[754]

You will need to mount master cylinder, linkage a pedal.. we're you thinking of using the alloy sideplates ?

[BenelliSEI]

Not to suggest anything illegal, but why not just switch over the headstock plate (from the K to the F) and make the stamped numbers disappear........

[scottly]

Because it IS illegal to alter the stamped numbers.

[BenelliSEI]

Very true! In Ontario, it is possible to reregister a frame (or motorcycle) with no known paperwork. The DMV will do a search (for a fee) on the frame number. If it has no known title, a sworn affidavit stating where and how it was legally obtained, can result in a new title being issued. Is that possible the the US?

[scottly]

If the # has been altered, the bike can be confiscated, and the owner can possibly be prosecuted, at least that's how it used to be in California. Every state has different rules regarding getting a title for a vehicle with no paperwork.

[754]

Iv you just change tag,then the frame has 2 sets of numbers. .

[low-side]

You would need to swap the entire head stock to avoid the 2 sets of numbers issue.  In most states that's legal (or at least not illegal). Personally, I would look into a bonded title or something similar.  In Nebraska, the bond period is 3 years.  It may sound like a pain, but it's a better situation than we have here in Ohio.  Here, no title means no title.  Of course, if you're doing a cafe build, the K frame would be the fast track; you just need to fabricate a mount for the rear master cylinder.

[RAFster122s]

What about differences in brake pedal, kick starter arm and Kickstarter shaft?

[754]

Late model kicker , are on both K and F models , and fit all years.
They have more offset , and likely better for rear sets.
 If converting to a disc, you will need to mount master cyl, linkage and brake arm, which may mean , the K type mount, may get in the way.