Sorry if you've tried this already but I had this issue with my deore lx shifters and I was about to bin them. I sprayed a load of GT-85 into the mechanisms and shifted over and over until they eventually started working again. I think the bike had sat idle for years and all the old grease was blocking the pawls. Now they work like a dream.
Sorry if you've tried this already but I had this issue with my deore lx shifters and I was about to bin them. I sprayed a load of GT-85 into the mechanisms and shifted over and over until they eventually started working again. I think the bike had sat idle for years and all the old grease was blocking the pawls. Now they work like a dream.