Square Shoulder vs Round Shoulder Bearing Caps for Twin Cam

The expert opinion available on this net would be appreciated.

I have a 681F6015 “virgin” block for sale on ebay right now. By virgin I mean that it has not been bored out and still has the 82.5 mm bore and a crankshaft that appears to be original and not re-ground. The caps appear to be exactly like the caps on a recent 701 block that sold on ebay a few days ago.

What I need to know, so that I can represent it correctly, is if these caps are the “square shouldered” or “round shouldered” I have had two different “expert opinions” one says they are definitely Square Shouldered and the other says they are definitly Round Shouldered - are there any referees out there?

Attached are the pictures. One is of the 701 caps from the ebay sale a few days ago and the rest are from my block now on ebay. I really want to properly represent the merchandise so you exediate help would be appreciated.

I am open to a phone call if that would help 931-205-0215

Dan Stover






your main bearing caps are of the “square shoulder” type.

cheers
Rohan

Square

John :wink:

Square.

‘Square’ refers to the flat horizontal bottom face, and ‘round’ is when the bottom face is curved concentric to the crank (viewed end on). If you have the Robinshaw & Ross Elan book, see p.70 - a picture speaks a thousand words… :slight_smile:

:arrow_right: Matthew