Topic: !975 cb750f SS transmission compatibilty??

[Lazerviking]

Does anyone know if the transmissions for super sports are the same or interchangeable??

I have a 1975 CB750f SS and need to replace these parts;

the mainshaft 2ND and 3rd gear(part#23431-392-000)
the mainshaft 4Th gear(part#23450-392-000)
the countershaft 3rd gear(part#23460-392-000)

On eBay I'm only seeing entire transmissions for 76, 77, 78 super sports, but don't know if that would work for me?

HELP

Or does anyone know where I could purchase these parts individually? I'm willing to go either direction but don't want to break the bank anymore than I already have.

This is what I found after opening my crankcase...

[Jerry Rxman Griffin aka MuthaF'er]

First off here's a wonderful tool for you to use to mix and match and order parts:

http://www.motogrid.com/pages/OemParts?aribrand=HOM

You can look up parts/parts numbers/see nice pictures and once you obtain that part number you can see which models parts cross reference your model. You will also notice 'superceded parts'. Even though the numbers may be different a superceded part is an updated part number and it's a direct replacement usually if not always.

The 75/76 750F transmission uses some different gears vs all the predecessor 750's to achieve different gear ratios to achieve quicker acceleration. The 77/78 750K uses the 75/76 750F engine with it's few upgrades (for performance) and I'd ALMOST bet that the transmissions are identical as well as the 77/78 750F. I said ALMOST plus I showed you how to look up parts/models/and how to cross reference parts for interchangeability. ALMOST isn't good enough unless you cross reference and it's EXACT.

You will probably find that new transmission gears are NOT available from Honda. They do come up on EBay but are pricey usually. Do NOT buy them unless the numbers match or the numbers are superceded as evidenced by your new newfound cross referencing skills.

So, replacing the entire tranny is one option and perhaps the best. The gears would mesh that way. Or maybe replacing that one-half and mixing and matching would probably work fine even though the 2 halves didn't grow old together and mesh perfectly. With that said how are you going to know the quality of used tranny gears and shafts?!! Or the bearings for that matter.

How about finding a donor engine?! You'd get a tranny and some more spare parts too. See what you can work up here first then resort to EBay. 

[Lazerviking]

Hey Jerry,

Thanks so much for sending that link. I've got it bookmarked already and looks like an incredibly helpful resource. Awesome beyond belief.

I think replacing the entire transmission is the way to go too. I've been looking around in my area for a parts bike but so far nothings popped up. I do feel a bit skeptical of getting a parts bike seen as how I have no idea of the condition that its components are in. What is the best resource for finding quality used parts?

Thanks again!

I feel like such a rookie.

[Jerry Rxman Griffin aka MuthaF'er]

Experience and luck are the 2 main things you'll need. A little friendly help and a trust worthy source are always good too.    If you rely on EBay you'd better be pretty good at reading the ads and the sellers too.