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Crankshaft & big ends

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fothers:
Happy new year to all,

I've had some nasty knocking coming from the bottom of the crankcase on my 1976 F2 which I thought would probably be the big end shells or crankshaft so I have just stripped it down to the cogs and got split the con rods. The problem I have is this:

In the Haynes manual it states that replacement shells should be sized according to a letter between A-D and a paint spot, and then read from a table in the book... the problem is that my con rods are stamped with an \"E\" and there is no paint spot anywhere in sight. The table on p34 (attached), does show an \"E\" mark but this is referring to bearing selection for the 400F. The bearing shells have codes stamped on the back, but these aren't explained in the manual.

Does anyone know what's going on here? Is this a typo? Is there another method for sizing?

PS, I also need torque settings for the bearing cap nuts and any other relevant bits (I can't find them in the manual).

Cheers,
Pete.

fothers:
EDIT-

The attachment was too big, here it is now.

Pete.

Post edited by: fothers, at: 2006/01/08 13:03

SteveD CB500K0:
Pete - the attachments still don't seem to have worked and it's so long (25 years) since I last worked on the bottom end of my old 500/4!

Post this question here:   www.sohc4.net

I'm sure there will be someone there who can help you.

JonnyB:
Hi Fothers,

Sorry you couldn't upload your image, in order to save space and stop peeps acidently uploading massinve files images are restricted to a maximum of 500 pixles wide and 500 pixel high, and max size of 1024 kilobytes (1meg).

Hope this helps.

John

fothers:
Cheers Chaps,

I took the shells out and they are all marked with an \"A\" and \"STD\" on the back face, which gives me an idea of how to size them from the chart (that's the pic I was trying to upload) - ie, they are all standard and correspond with what would be colour codes of Black for both crank and big ends. They are a bit discoloured and have minor radial scoring so I'm going to replace them. The crankshaft appears to be in good nick and measures within tollerances (though I haven't measured the run-out yet).

The clearance ranges for the bearings are 0.022-0.048mm for the crank and 0.020-0.045mm for the big ends... and I need to measure these so I make sure everything will turn properly when I put the new bearings in.

So... just sent off for come \"Plastigauge\" - I'll let you know how it goes.

Cheers,
Pete.

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