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Hi folks, Just wondering if anyone has seen this before? These are the heads for my 31V and you can see the 2 fins I’ve got the calipers pointing at slope down towards the edge whereas the same fins on the other head are flatter then rounded at the end. You can also see the difference between the 2 smallest fins at the front, left is flat whereas the right slopes down.
Both heads have 12.5 cubic inch, low compression, chambers and no other letters or numbers stamped or cast other than “PATD 11-13-23”. So in that regard they’re correct for my bike.
You can also see a difference in the clearance between the boss for the primer cup and the nearest head bolt hole. One the left there’s a slight gap between them whereas on the right the head bolt surface actually cuts into the boss.
It’s always possible that one head has been replaced from a later model or with whatever the dealer had on hand. Or is it simply foundry tolerances?
Either way they’re going on the bike. Purely curiosity on my behalf.
Fins.jpg
Primer.jpg
Both heads have 12.5 cubic inch, low compression, chambers and no other letters or numbers stamped or cast other than “PATD 11-13-23”. So in that regard they’re correct for my bike.
You can also see a difference in the clearance between the boss for the primer cup and the nearest head bolt hole. One the left there’s a slight gap between them whereas on the right the head bolt surface actually cuts into the boss.
It’s always possible that one head has been replaced from a later model or with whatever the dealer had on hand. Or is it simply foundry tolerances?
Either way they’re going on the bike. Purely curiosity on my behalf.
Fins.jpg
Primer.jpg
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