Author Topic: Gearing question  (Read 857 times)

eddietheengineer

Gearing question
« on: February 18, 2024, 11:31:21 AM »
I'm not sure where to put this--but it kind of fits in mechanics/maintenance.

I've recently switched from a 53/39 + 11-28 Sram 10 speed road bike to a 50/34 + 11-28 Shimano Ultegra mechanical 11 speed road bike. I found 99% of the time with my old bike, I'd spend it in the small chainring, so I figured the smaller front crank would help out and give me a bit more gearing options on the low end.

However, instead I've found something very annoying--when I'm in the small ring, I can't go very far down the cassette before the chain starts rubbing on the front derailleur, even with the front derailleur trimmed to the first click. Also, on the big ring, I can't go very far up the cassette before the chain starts rubbing, even with a trim click, and there aren't a lot of gear combinations in the middle between those.

I end up regularly being frustrated since a lot of my base riding ends up being jumping back and forth between the big and small ring trying to find a gear that fits my cadence without rubbing. I thought it was a front derailleur alignment issue, but since it's pretty evenly rubbing both directions, I don't know how I'd be able to adjust cable tension and get better behavior. Maybe there's something in the height of how high the front derailleur should be? or angle alignment?

Do you all have any advice?



electrolux

Re: Gearing question
« Reply #1 on: February 18, 2024, 12:21:57 PM »
Maybe you need some spacers to get the chainline correct?

There are some good videos on YT for adjusting your FD from parktool, they go through angle adjustment and height adjustment.

eddietheengineer

Re: Gearing question
« Reply #2 on: February 19, 2024, 07:17:33 PM »
Well, I went out for another ride today and realized that my crank arm was coming loose--the crank had maybe 1/2 to 1 chain width of play side to side. That would explain the poor performance  :D