I got this used bike recently and I was trying to change chainring. I ordered a Hope R22 32t chainring and after I mounted (I hope you can see from the photo) the chain doesn’t sit well due to the crank arm. The chain touches the arms. In my mind I have two options: one is file down a couple of mm in the inside the crank arms. So the chain can sit properly or to get a 34t chainring. Obviously I would like to keep the 32t chainring.
by JoanFontcuberta
3 Comments
I would file the arms, but that solution might be frowned upon. I would aim to keep the metal thickness at least as thick as what is shown at 3:00 on the first picture. Something like this, but rounded a bit nicer than my line.
https://preview.redd.it/7wu24d2v3b1e1.jpeg?width=1170&format=pjpg&auto=webp&s=8a2b007ca59eff36f94abad158420201e85ee8d3
also – you used an old chain with new chainrings ?
dude, if you have that much spare money laying arround – why not give me some 😀
in more seriousness – not dirrectly your problem yet, but it seems, that there is also another problem – your chain is stretched enough to not engage teeth correctly. Basically even if you solve your problem – you will ruin the chainring in no time
as for your problem – an suboptimal solution would be to install some shims to between spider and chainring. not much, but enough to give outer plates space between spider and chainring
And I don’t mean common washers. instead : [https://eshop.wuerth.de/Product-categories/DIN-988-steel-plain/14013514070101.cyid/1401.cgid/en/US/EUR/](https://eshop.wuerth.de/Product-categories/DIN-988-steel-plain/14013514070101.cyid/1401.cgid/en/US/EUR/)
you could also use common washers, just buy couple hundred, get some really good calipers ( like original mitutoyo, or something like that) , and sort out those washers. however, you have to be careful – washers tend to have uneven thickness and sometimes are not that flat.
ones in the provided link are actually shims not washers.
Yeah, I wouldn’t think twice about filing away some of the crank arm. You wouldn’t even need to file uniformly through, just notch enough to evade the chain.
Otherwise, I’d add some spacers.