|Are all gears available?||Gerbila|
Sep 10, 2003 12:33 PM
|I'm having some probs w/ chain rub on my ultegra 9 spd setup. Basically in the inner ring on the front I can't access the 3 smallest cogs without rubbing the outside of the fr der cage. I have tried all manner of adjusting limit screws and the tension barrel on the downtube to no avail. It kind of sucks because to get into some intermediate range gears I have to upshift to the big ring and use a larger cog in the back, which I realize creates a bad chain line. But I don't see what I can do to fix things. The whole shifter trim thing befuddles me. The front shifter has an intermediate position right beyond the one for lower gear, but that seems to push the derailleur too far out, into a no-man's land where it still upshifts the chain to the big ring, but causes chain rub on the inside of the der cage. I wish there were some way to adjust the trim settings or whatever. I'm about to throw in the towel and just take it to a shop. But I would rather learn to deal with this on my own. Muchos gracias.|
|re: Are all gears available?||innergel|
Sep 10, 2003 1:55 PM
|I have the exact same problem. This all happened when I switched to a SRAM chain from my Ultegra chain. I tried all the front derailler adjustments to no avail. I took it to the shop to get fixed and it turns out that the chain is not rubbing on the front derailler, it is rubbing on the 52 chainring. The wrench at the shop said there was nothing I could do to fix it, short of trying a different chain or not riding in those gear combinations.
It is possible to reduce the rubbing a bit by properly adjusting your front derailler, but I bet you'll never totally get rid of it without swapping out a component or two. You should easily be able to get rid of the rubbing in the "intermediate postiion" with a minor front derailler adjustment. Here is a good article on how to do that:
As an aside, I think it's ridiculous that this type of thing happens. I've heard all the "you shouldn't be riding in that combo" talk and think it's total BS. Why would you build a product that should not be used through it's full range of operation? I'd sooner have a 7 speed cassette that I could use all of than to have a 9 speed where you can't use the top and bottom ranges. This is one of my pet peeves re: bike components.
|Check your chain line||Kerry Irons|
Sep 10, 2003 5:40 PM
|A line from the center of the chain rings (middle ring if triple) should pass through the center of the cassette. Use a carpenter's straight edge to check this. If the chain line is right, you should have rub only in the small/small combination typically. You can elimnate the rub by installing a spacer between the right BB cup and the frame. Your should would have the spacers. If you chain line is right now, then adding the spacer could make the large cassette cogs problematic, but you'll have to try it to find out.|| |