*OS .91FX Neddle Valve*
#1
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I'm going to purchase the OS .91FX and the OS 1.08FSR soon and my question is about the OS .91FX. The guys at some of the local flying fields are having trouble with the high speed neddle valve backing out and then going lean in the air and shutting off. Some have replaced the neddle valve with a GMS 1.20 neddle valve and it seems to do better. We have heard that in the past few months the new engines that are being produced are coming out with a different high speed neddle valve assemble. Can you fill me in on just what is taking place before I make a purchase? How can a person tell the difference between the old one and the new one if this is the case. Thanks.
#2
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The current needle valve is mounted to a metal bracket that screws to the rear cover, and has a plastic housing. The older version had the bracket molded as part of the rear cover. All new engines should have the new version unless it's been laying around the retailer for some time. The new version is over a year old.