Bicycle Mechanics - Kind of Anal Retentive

I am kind of nutty about cleanliness and mechanical correctness so I try to clean the chain, cogs, chainrings, etc frequently. I was cleaning up after the Tour de Tucson this weekend and noticed a few things. First off, when I put the rear wheel into the dropouts and then check the wheel centering between the seat stays it seems that it is off center by at least 1/8 inch, or there abouts. Is this a reasonable misalignment or am I just being crazy about this stuff? (Bike is Cannondale R1000, Shimano Ultegra derailleur, SRAM cogs.) Further, one of the rear dropouts seems to be adjustable, or some such thing, as it is attached to the rear of the Chainstay with two allen screws. Is this some sort of wheel alignment mechanism to fix what I am seeing??

The second issue is that when I check the alignment of the rear derailleur with the cogs it appears that the jockey pulley and tension pulley are not exactly parallel with the plane of the cogs but are at a slight angle from it. How much out of alignment is acceptable??? OK, OK, so I fell over twice (failure to unclip at a stop) and may have bent it. Is bending/straightening the dropouts/hanger the only way to fix this and is this something I should do myself. Keeping in mind that I am somewhat mechanically inclined as I do all of my own car, boat, and home maintenance so I am not too afraid to try anything (at least one time).

OK, thanks in advance for any advice/help. I really appreciate the info on the forum. It has been a great help in the past.

Guy P.

Further, one of the rear dropouts seems to be adjustable, or some such thing, as it is attached to the rear of the Chainstay with two allen screws. Is this some sort of wheel alignment mechanism to fix what I am seeing??

The second issue is that when I check the alignment of the rear derailleur with the cogs it appears that the jockey pulley and tension pulley are not exactly parallel with the plane of the cogs but are at a slight angle from it. How much out of alignment is acceptable??? OK, OK, so I fell over twice (failure to unclip at a stop) and may have bent it. Is bending/straightening the dropouts/hanger the only way to fix this and is this something I should do myself. Keeping in mind that I am somewhat mechanically inclined as I do all of my own car, boat, and home maintenance so I am not too afraid to try anything (at least one time).


It's a replaceable derailer hanger.Has nothing to do with wheel alignment..... If shifting is ok,hanger alignment is ok.

I am kind of nutty about cleanliness and mechanical correctness so I try to clean the chain, cogs, chainrings, etc frequently. I was cleaning up after the Tour de Tucson this weekend and noticed a few things. First off, when I put the rear wheel into the dropouts and then check the wheel centering between the seat stays it seems that it is off center by at least 1/8 inch, or there abouts. Is this a reasonable misalignment or am I just being crazy about this stuff? (Bike is Cannondale R1000, Shimano Ultegra derailleur, SRAM cogs.) Further, one of the rear dropouts seems to be adjustable, or some such thing, as it is attached to the rear of the Chainstay with two allen screws. Is this some sort of wheel alignment mechanism to fix what I am seeing??


It's more likely that your wheel is not properly dished, or centered with respect to your hub. Try taking it out, flipping it around and putting it back in the dropout. You'll probably have to shift the derailleur in the smallest-cog position to get it out of the way (and even then, I'm not sure it'll be totally out of the way, so you may have to take it off). If it's equally off-center in the same direction (with respect to the frame), then your frame is misaligned; if it's equally off-center in the opposite direction, then it's your wheel. If something else happens (say, it goes right to the center), then it's likely that both are misaligned. But, even if it's slightly misaligned, it probably won't make any noticable difference in terms of durability or ride quality, so don't sweat it.

The screws you mention just hold on the replaceable der. hanger, as sydney said. If you break or bend your hanger, you can just replace it with a new one.

Check if the brake pads are the same distance from the rim on each side of the wheel. If so, then it's probably been that way and maybe you're just noticing it.

Make sure you're not checking the alignment using the brakes.
The issue where the jockey pulleys aren't parallel with the cassette is a problem.
Yes, it is the only way to fix it. The shops have a tool for checking the hanger alignment. Cheap and quick.
You did not mention any problem with ratcheting, clicking or skipping when shifting or anytime. ???

OK, thanks to everyone. To answer a few questions, no, there was no skipping, shifting problems, racheting or anything like that. The only comment I could add is that when shifting from a smaller cog to a larger cog it was a nice smooth click-click-click as it goes up the cogs. When shifting from a larger cog down to a smaller cog there is a distinct "clunk" especially if I have any pedal pressure at all.

So, I got out my calipers, depth guages, etc. and here is what I found. I checked the "Dish" of the rear wheel and it was off center by .015 to .020 which it seems to me is entirely acceptable, in fact not bad at all. But the hanger for the derailleur is bent rather badly and that explains the misalignment of the guide and idler pulleys. Tomorrow I'll make a tool to more accurately check the alignment of the derailleur hanger and straighten it out. I am sure that will fix me back up.

Again, thanks to everyone.

Guy P.