Originally Posted by
ArgoMan
"The trim position of a lot of shifters"
Sorry, but I'm ignorant of what a trim position is. Can you explain a bit? I've raised and lowered the derailleur, moved it in an outward, tightened and loosened the cable tension. Yet I still get some rub. I find it so frustrating having a chain on one bike rub when the chain on my 105 is just so smooth. I can't imagine that Shimano designed a mechanism (Sora) that they know is going to rub a bit and leave it at that. So, I have to be doing something wrong. Thanks for the reply!
Originally Posted by
ArgoMan
Yes! I think this is the answer. Rode it again and I was like a falcon cutting through the wind! No noise, so smooth. But just the fact that I have this mechanism on my bike that doesn't work as intended, or as efficiently as it should, just drives me nuts! I want to fix it!
Trim position is a click within the front shifter that moves the front derailleur ever so slightly inward when the chain is on the large ring. It exists to reduce chain rub when the chain moves across the cassette's cogs. As the chain moves from cog to cog, the chain's angle changes and eventually the chain touches the front derailleur a bit. So this small click adjustment moves the front derailleur in a slight distance, like less than 1mm, which then keeps the chain from rubbing when you are using that rear cog.
The front shifter is only 1 click up from the small to large ring, but its 2 clicks when you are in the large ring to move the chain down to the small ring. You dont really notice if you push the shift lever in all the way as that just overtakes the trim option and the chain moves to the small ring.
Take the bike to a shop if you cant figure out how to set it up for there to not be any rub.