My 250 has had all the carb parts except the outer body replaced. Have tried 106 and107 pilot jet. Idles well and throttle response fine on stand at home however there is an annoying unevenness under load out riding on the first 3-5mm of throttle which disappears when the throttle isopened further. The exhaust silencer is a non standard alloy type which I am told is a Sammy Miller one sold as an accessory at the time. Any guidance much appreciated!
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