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You are correct you would have to buy the bearings to check with plastigage. With the second set of numbers you are now just slightly out of low side spec of 1.7500 by 1 and 2 thou. You might be able to get by with this with standard shells as long as the crank is not scored. Also are you checking in multiple position to determine if the wear is oval. You must regrind the crank to use oversize shells. Recommended clearance on the bearing to journal is 1 thou. Do you have a workshop manual? Commando cranks must be ground with a radius (see manual). Most automotive machine shops are reluctant to do this because it is not common practice now and they have to specially dress the stones to do. My recommendation would be to take it to an automotive machine shop and have them measure it and inspect it. You can show them the grinding proceedure but you may have to send it to a Brit bike shop to have the actual work done.

<blockquote data-quote="htown16" data-source="post: 692562" data-attributes="member: 1322"><p>You are correct you would have to buy the bearings to check with plastigage.&nbsp; With the second set of numbers you are now just slightly out of&nbsp; low side spec of 1.7500 by 1 and 2 thou.&nbsp; &nbsp; You might be able to get by with this with standard shells as long as the crank is not scored. Also are you checking in multiple position to determine if the wear is oval.&nbsp; You must regrind the crank to use oversize shells.&nbsp; Recommended clearance on the bearing to journal is 1 thou.&nbsp; Do you have a workshop manual?&nbsp; Commando cranks must be ground with a radius (see manual).&nbsp; Most automotive machine shops are reluctant to do this because it is not common practice now and they have to specially dress the stones to do.&nbsp; My recommendation would be to take it to an automotive machine shop and have them measure it and inspect it.&nbsp; You can show them the grinding proceedure but you may have to send it to a Brit bike shop to have the actual work done.</p></blockquote><p></p>

[QUOTE="htown16, post: 692562, member: 1322"] You are correct you would have to buy the bearings to check with plastigage. With the second set of numbers you are now just slightly out of low side spec of 1.7500 by 1 and 2 thou. You might be able to get by with this with standard shells as long as the crank is not scored. Also are you checking in multiple position to determine if the wear is oval. You must regrind the crank to use oversize shells. Recommended clearance on the bearing to journal is 1 thou. Do you have a workshop manual? Commando cranks must be ground with a radius (see manual). Most automotive machine shops are reluctant to do this because it is not common practice now and they have to specially dress the stones to do. My recommendation would be to take it to an automotive machine shop and have them measure it and inspect it. You can show them the grinding proceedure but you may have to send it to a Brit bike shop to have the actual work done. [/QUOTE]