I have owned a 1995 Ultra with stock carburetted Evo engine for five years. Every winter I experience the same problem - it is slow to warm up and refuses to run smoothly and even misfires and backfires . I received advice that I should try pulling the enricher out about 1/2 way I tried this today and the bike performed great just like a summer day. Will this harm the engine ? Should I enrich the mixture for winter? and how do I do that? It performs great on summer days but I am retired and refuse to park it for the winter. Thanks.