Originally Posted by
1QwkSport2.5r
According to Frank Bowman's piston ring list, a bunch of the smaller Fox engines don't have pinned rings (.40 Schnürle, 45, 50, 59) as well as some Enyas (6002), and many others.
The Enya 6002 (both the 40 and 45) are baffled piston engines so the transfer and exhaust ports have multiple bridges to hold the ring in place as do all other non Schneurle engines. My OS 40SR needed a new ring which is unpinned but has a bridge in the exhaust port but Frank's list only showed a pinned ring. I queried him before ordering one and his reply essentially said Oops, got that wrong
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