Just found out Shimano shift cables are actually 1.1mm, not 1.2mm like I always assumed

I was rebuilding an old 105 groupset last night and measured the cable out of curiosity. Turns out Shimano uses a 1.1mm inner wire on most of their road shift cables, while SRAM runs 1.2mm. I had no idea they were different. This explains why some housing and ferrules are tight with one brand and loose with another. Found this on a Park Tool video about cable compatibility. Has anyone else run into shifting issues from mixing cable brands?

2 comments

2 Comments

sethp269d agoTop Commenter

Respectfully, I think people overthink this one. The 0.1mm difference is so small that it barely matters for shifting unless you're running super tight housing or ferrules that are way off. I've mixed Shimano and SRAM cables for years on different builds and never had a problem that wasn't caused by something else like a bent hanger or old housing. Most cable issues I run into come from bad routing or cheap housing that collapses, not the wire diameter. Are you actually feeling a shifting problem, or did you just notice this on paper and get worried?

felixb259d ago

Good point about bad routing and housing. That "super tight housing" bit you mentioned is the key thing I've seen too. In my experience, people chasing that 0.1mm with new cables will still get bad shifting if their housing is cut too short or has a sharp bend near the shifter, or if they're running cheap compressionless housing that just squishes under tension. The cable wire's diameter is usually the last thing I'd blame once the bike is clean and the derailleur hanger is straight.