Originally Posted by
downunder
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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I just did a quick glance at his most recent list and rattled a few off. It makes sense on the Enyas. The Foxes I listed and a few I didn't list like the .75, .78, and the multiple versions of the .59 use unpinned rings. Nonetheless, there are Schnürle 2-strokes that have ringed Pistons where some are pinned and others are not. As far as the topic of the thread - I believe most if not all modern Tigres have pinned rings. Old ones? No idea without doing some digging though I don't think it matters.
S series are pinned, G series are pinned, X series are mostly all pinned. V series are mostly unpinned. The G21 series are unpinned. FWIW.