Cam sprockets

[Matt_Harrington]

Rummaging for parts to finish off my engine rebuild I discovered I have 2 different types of cam sprocket - is one later or earlier than the other?

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[Nurse Julie]

Never seen the type on the right before 🤔🤔🤔

[Matt_Harrington]

The one on the rights is as per the parts diagram - (Issue 4 - 1977)
Deciphering things a bit more, the one with cut outs is an earlier one and the solid one is later. I presume the solid one is a bit better.
I wonder why it was beefed up so much?

[Nurse Julie]

The one on the rights is as per the parts diagram - (Issue 4 - 1977)
Deciphering things a bit more, the one with cut outs is an earlier one and the solid one is later. I presume the solid one is a bit better.
I wonder why it was beefed up so much?

To help stop cam chain rattle noise. I remember now hearing about those very open ones but never seen one up close and personal.

[robvangulik]

I've been using one like that for years now, never heard a rattle yet
Less weight is always good!

[Laverda Dave]

My original 400/4 I restored back in 1991 has the thinner cam sprocket. When I restored the blue 400/4 about 5 years ago the cam sprocket was the two piece type. I can't say the thicker sprocket reduced the chain rattle noise though as I had both bikes running at the same time once to compare the original 400/4 exhaust with the DS replica. The 400/4 'rustle' sounded exactly the same on both bikes.

[Matt_Harrington]

I'm with Rob, if no significant difference then lighter weight has to be beneficial. I'll probably fit the one that comes to hand first!! 

[Trigger]

Same as on the CB750's. Solid sprocket on the early models , lighter cut out sprockets on the later models. 

[Matt_Harrington]

Graham, my parts book says the one with holes is the earlier one and the solid one is later. Did you mean the same for the CB750's or the opposite? 

[AshimotoK0]

Same as on the CB750's. Solid sprocket on the early models , lighter cut out sprockets on the later models. 

Are they interchangeable ? i.e later one can beused on K0

[Trigger]

Graham, my parts book says the one with holes is the earlier one and the solid one is later. Did you mean the same for the CB750's or the opposite? 

Sorry Matt, what i meant was the 750 was a lighter sprocket on the 750's latter .
The 400's had the solid sprocket on the 1977 and 1978, this was a superseded part to reduce the cam chain rattle. I did have a Honda sheet for this upgraded sprocket somewhere.   

[Trigger]

Same as on the CB750's. Solid sprocket on the early models , lighter cut out sprockets on the later models. 

Are they interchangeable ? i.e later one can beused on K0

Never tried it mate. Have always fitted the correct sprocket to the right cam shaft. It should not matter as it is the same size , just lighter