Topic: Unknown part help, please

[tomswift]

I have a problem perhaps someone here can easily help with....it has stumped me for days now

I am working on restoration of a '76 CB750F - came to me as a basket case and I have to sit and ponder where each part goes and how it fits... this part has me stumped, perhaps you can id it.

The engine was not entirely disassembled, but all covers were removed for polishing. Engine is out of frame. This appears to be a slider pad/tensioner for something like the cam chain, but I cannot see where it fits in the valve cover. It has slight marks on the flat surface (not deep) and is broken on one corner. It appears to mount by sliding onto a flat of steel, but no retaining holes are visible (as I see it)

If you can help, it sure would be appreciated. It is possible this does not go on this engine, but everything else in the boxes had a place...so I hope I can find the home for this item.


thanks in advance if you have the answer

[KB02]

Well, I agree that it looks like some kind of Chain tension part, but it's not something that I recognize.

Here is the parts fiche for the 76 F for the cam chain area.


The only thing I could think it might be is a broken off piece of #17, but it doesn't even look right to be that.

[Gregorymoto]

i dont think that is a motor part for a cb750, How wide is it?

[upperlake04]

 
Slider pad/tensioner seems like a good guess but as  suggested, not a Honda 750 engine part.  Pic of #17 

[tomswift]

Gregorymoto - it is about 7/8in wide

I have been through all the fiche on the CB750f... I keep thinking it goes inside the clutch cover or somewhere near the chain...but it is awfully clean to have been near the output sprocket

Again, all the covers were removed and polished, clutch mechanism is loose, engine is out of the frame. When it came to me the frame still have the wheels and handlebars on, all body work and engine off to the side

I have found one or two very small items in the boxes (like a socket and some rubber bits) I am certain do not go on the CB750F but almost everything else was present and accounted for.

I didn't mention it but this material certainly feels like cam chain slide components I have seen on many bikes. Kind of like an old bakelite...hard and heat resistant. Also, the wear down the middle seems wider than a cam chain...more like a 530 chain. Wear pattern is similar to cam chain tensioners, but wear is minimal. Bike has approx 20K miles on it. My experience is that 20K will raise a higher "lump" in the middle than is seen here.

Could there be something under the chain guard resembling this? Never heard or seen anything like that from Honda, but I am reaching here.

Thanks for all your input in advance.

[SteveD CB500F]

Does the primary chain have a tensioner?

Sorry if this is a stupid question - not a 750 guy...   

[Patrick]

That doesn't look like any part I remember from a 750 engine. But my 3 750s are Ks. I don't know if Fs had different parts. It certainly doesn't look like any part of the cam chain system. It's been a few months since I last had any 750s apart, though, so I stand to be corrected....

[Jerry Rxman Griffin aka MuthaF'er]

Does NOT belong to a 75/76 F. It's obviously rubbed against a chain on whatever bike it came from.

[tomswift]

I think I am just going to say "thanks" and try to end this here... I feel pretty certain that this did not belong to the CB750F... the engine is exactly like the K model with only minor changes (cam, jetting)

I was certain someone would say "oh yeah...this goes in the clutch/carb/chainguard/etc" but if not identified in the first few glances I am fairly certain it was just a confusion factor tossed in the basket.

I will not throw it away (for a while)...if someone recognizes it from a Nissan truck or a Suzuki 4-wheeler, let me know. Thanks

[75modrat]

I am probably way off. I am Polish, it happens often. However, it looks to me a little like the rubber piece that sits on the frame to keep the gas tank from hitting the frame just in front of the seat. I apologize if I am way off.

Frank

[jtb]

Nothing like that was in my 77 750F motor.