Bicycles Network Australia - Australian Cycling Forums

by **jacob_T** » Mon Dec 03, 2012 6:15 pm

I'm fairly new to riding bicycles, and even newer to bike maintenance.

When I was riding yesterday I noticed that when I was in my lowest gear (largest on cassette, and smallest on crankset) my chain was rubbing on the front derailleur (on the side closest to the bike).

I decided to have a crack at adjusting the derailleur rather then taking it into a shop, because I figured I would have to learn this eventually, anyway.

I've managed to use the adjustment screws to move the derailleur across so it's no longer rubbing, and have run through all the gears.

The only problem I have now is when the cassette is in its smallest cog, and the crankset is on the small chain ring the chain grinds against the wall of the derailleur closest to the bike.

Now this is not as much of an issue, because I can shift up to the large chain ring to avoid the scraping, but I was just wondering if technically I should be able to tune the gears to the point of being able to use any gear combination?

by **BNA** » Mon Dec 03, 2012 6:18 pm

by **reefer** » Mon Dec 03, 2012 6:18 pm

You can, I did it on my wifes Orbea, even though the LBS couldn’t get it right.

Google a heap of videos and learn. I ended up adjusting the cable as well as the adjusting screws.

by **toolonglegs** » Mon Dec 03, 2012 6:38 pm

Are we talking road bike here?... if so you probably have a half click trim adjustment on your levers just for this reason.

by **jacob_T** » Mon Dec 03, 2012 6:48 pm

Yep.

Shimano 105 Groupset.

Googling that right now.

by **DoogleDave** » Mon Dec 03, 2012 6:50 pm

You should be able to tune the derailleur so it doesn't rub for any gear, however it is a common "no-no" to use your small(front)-small(rear) OR large(front)-large(rear) as your chain is on quite a large angle and can put extra stress on your chain and components.

In saying this, if you need to use it then use it - but the traditionalists will tell you that when on your small chain ring, as you near your smaller cassette gears you should change up to the large chain ring and drop the rear cassette back a couple of gears and away you go, straightening the chain line.

In my experience I find that I usually get to around my 5th or 6th gear on the small chain ring and then I change up to my large chain ring and drop back to 3rd or 4th and keep going - unless I need to spin in which case I may stay on the small chain ring and push it another gear or two on the cassette and up my cadence.....but the situation and conditions at the time dictate this for the most part.

Good on you for having a go. Keep at it as once you learn how to do it you'll save yourself time and money!

Dave

by **jacob_T** » Mon Dec 03, 2012 6:55 pm

DoogleDave wrote:You should be able to tune the derailleur so it doesn't rub for any gear, however it is a common "no-no" to use your small(front)-small(rear) OR large(front)-large(rear) as your chain is on quite a large angle and can put extra stress on your chain and components.

In saying this, if you need to use it then use it - but the traditionalists will tell you that when on your small chain ring, as you near your smaller cassette gears you should change up to the large chain ring and drop the rear cassette back a couple of gears and away you go, straightening the chain line.

In my experience I find that I usually get to around my 5th or 6th gear on the small chain ring and then I change up to my large chain ring and drop back to 3rd or 4th and keep going - unless I need to spin in which case I may stay on the small chain ring and push it another gear or two on the cassette and up my cadence.....but the situation and conditions at the time dictate this for the most part.

Good on you for having a go. Keep at it as once you learn how to do it you'll save yourself time and money!

Dave

Yeah, that's how I usually ride too, which is why I'm not so worried, but was just wondering whether I should be able to tune it so theoretically I could use all gears combos.

Reading up on trim adjustment now. Not sure I fully understand it yet. Might go have a fiddle on the bike.

by **jacob_T** » Mon Dec 03, 2012 7:07 pm

It all makes sense now!

Can't believe I've spent all this time and never realised what trim adjustment was.

Well. Looks like I've fiddled with my derailleur for nothing. Hopefully it's not too out of whack now.