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Are there differences between SOHC engines?

lkstk

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I am replacing the engine in a 76 cb750F super sport, and there aren't any used ones that I can find. Does anyone know if the K motor fits the F frame? I have found plenty K motors, but I don't know what troubles I will encounter, or if it bolts right in. Any insight would be appreciated.
 
I don't think there's much of a difference you'll notice between the K and F for mounting purposes, but there are differences in sprocket offset with the '77-78. I think there's a 10mm difference at the engine and the rear sprocket cush drive is different also because of that sprocket offset. So I think you're fine with a K engine from a '76 and earlier.

Don't run with this, rather wait for someone with more experience to chime in... I just wanted to point out that the year can make minor differences as well.
 
Any sohc motor will bolt in. Offsets started with the 77. Stick with a 76 and older and you should be ok. The only difference between the K and F in these years in different exhaust and different jetting. Physically they are the same with minor internal differences. If you do run into chain alignment issues Cycle X offers different offset sprockets.
 
Hey guys,

New to forum, this is my first post.

There's a local listing near me for a '76 cb750f. It's got 45k miles on it and needs a little TLC. The only described issues the bike has is that the engine has a hairline crack in the lower case and the gas tank needs to be restored due to a couple pin sized holes.

I plan on doing a full engine rebuild because it's got high miles + that hairline crack. I have the funds to rebuild the thing properly, so why not?

Here's my question: Will a '76 cb750k engine case fit the '76 cb750f engine? I know I need both top and bottom cases as they are built for each other. I ask in the circumstance that parts like engine cases for the K may be more available than the F. I'd like this build to be show worthy so doing it right the first time is of upmost importance.

I'm a noob when it comes to vintage honda's so any and all advice would be greatly appreciated! Thanks in advance!
 
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