This is an easy fix. These STI shifters (integrated brake/shifters or brifters) were advertised on eBay as not shifting. I bought them at a good price, knowing I could probably repair them. When I got them, they had the problem I they would have where the pawls just don’t seem to catch. Most times when shifters don’t shift (trigger shifters, STI shifters), the problem is the pawls get stuck with old grease. The old stiff grease just needs to be cleaned out and the shifter re-lubricated. It’s an easy fix. In this video, I clean out the old grease using degreaser, and then lube the shifter with Tri-Flow Superior Lubricant.
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