Honda CB750 Sandcast

Unique parts

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Bickle

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Being a novice in the sandcast circles I would like to ask some questions that will help me with my daunting task of restoration. Hopefully not too repetitive for you experts.
Pistons...are they unique to the early 69/70 or do later years work?
I believe carb kits are unique that way.
How do you determine a genuine sandcast set of guages?
I know the key switch/ rear rim/ side covers/ chain guard/ seat/ clutch cover?/ frnt brake assembly/ front fender/ oil cover/ carbs and mirrors are unique to the sandcast.
I'd be interested in hearing what the other items are and how they are distinguishable from later years.

I'll defer to the experts on this one.

Thanks guys

Steve


chrisnoel

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The bolts.... What ever type of #8 you have on the bolts is the type you should get for replacement of non original bolts. Basically all non-chrome bolts should be the 8 dull coating bolts.

The on/off controls = black on/off switch.

Seat = duck tail with seams that are not like later models.

Seat pan = no part #s.

Exhaust pipes = no #'s..... HM300's are acceptable for restoration.

Air Box.... flat sides.

The instruments should have a thin chrome lense bezel, domed plastic lenses, and a red zone at 9k. The drive gear "under the chrome bottom cover" for the sand cast tachometer is also sandcast.


736cc

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Actually, K0's (after serial # 1007414) share more parts w/ late sandcast motorcyles than the early sandcast's share w/ late sandcast's. The early sandcast's much more unique in their details. Frame is different (headstock bracket), as well as exhaust clamps (much chunkier), carbs (thinner cables and caps), choke lever (longer), airbox (smaller brackets w/o rubber packing), horn (left side on early and sometimes grey), rear hub (2 internal holes instead of 4), oil filter cover (smooth on early), gauge numerals (subtly different color and detail), gauge rubber mounts (locating pip), front brake hoses (short, straight necks), fuel tank (different shape underneath), centerstand (simpler), exhaust baffles (fatter), candy blue-green paint (early sandcast's were more green in color); and there are many more. The point is, Honda did not make wholesale changes when they went to diecast, they made changes constantly, 1 or 2 at a time from the very earliest releases. The EARLIER the sandcast, the more unique it is. Honda Parts Manual does a good job of cataloging these changes. And not everything "etched in stone" either; I've come across some "not correct" details on unrestored bikes. I am very lucky recently to have found an early, all-original, unrestored sandcast that is straight as an arrow and untouched since new, and will remain in that state of grace as long as I own it (I'm resisting even washing it, - bike has a superb patina). It will be the subject of a photo essay w/ detailed documentation of all this good stuff, someday.


elisent

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Great stuff "736cc" Are there any numbers or ratios on how many red to blue were made? Were the early sandcast carbs and cables different than the "28" carbs and 5mm cables on the first 17000 that was part of the recall. Can later carbs be made to look like early carbs by just changing the caps and cable? Inquiring minds want to know... I can't wait to see pictures of this new original find. Please document this sooner than later. I know you got hammered with the snow this past weekend. This should give you plenty of time.

I've restored some old HDs and a late 36 Knuckle has more in common with a 37 than an early 36. Especially in the days before cad computers most totally new models have many # to # changes. The biggest thing you learn when researching a bike for restoration is that there are no always and nevers. There are tons of exceptions to factory documentation and parts books. Especially with the first year of a model. This is what makes it fun and sometimes a little frustrating. Eli