WildRalph

Installed L.A. R.D....Finally got new chain and had to size it, cuz swapped rear cogs to a 14 - 28. Testing it reveals that wont shift to the 28 tooth cog. Despite adjusting the derailur. I have some theories, but not 100%. 1. R.D. cable is too tight? 2. Chain is too slack? ...wrong plate sequence for quick-link, so had to push to next link, then +2 rivets?...or something wrong with derailur/spring? Any help appreciated, tnx!

WildRalph

Sorry, was feeling Bold! Lol. Another alternate theory, is the integral RD hanger is too high. My gut says the cable is too tight. Havent had time to slacken the cable to see.

cdmurphy

Do you have any room to move the wheel in the dropouts? Often older road derailleurs will have trouble with a 28T, as they're designed with the jockey wheel in close to improve shifting performance. I've had good luck in marginal cases by moving the wheel back, this gives a little more clearance, and is often enough to get it shifting fine. If that won't do it, you'll either have to stick to a 26T large cog, or look into a longer cage derailleur. The long cage will often position the jockey wheel lower to allow larger cogs. Shifting won't be as crisp though.

One other possibility, would be to shorten the chain. A tighter chain will rotate the cage forward, and may give you the needed clearance. This would only help with the large-large combo, you would still have trouble on the small front chainring.

Slightspeed

I was able to run a 6 speed 28t on my Legnano (old Campy Gran Sport RD) by backing out the dropout screws and pulling the wheel back. I didn't need to mess with the chain length, sometimes if I forget and go big big, the bike barks at me, but it isn't too big a deal, momentarily.

ATPAH

I did the same thing with my 1986 Bianchi when changing out the cassette to run a 28t with the original LA RD.

WildRalph

Thanks folks. Here is what is weird. When i am off the bike, pedaling by hand, the chain goes right on 28 tooth, lickety split. But when i test rode it the other day, it would not go on, like shift lever was out of cable. The cables are brand new. Checked again by hand last night, worked perfect. Unfortunately unable to test ride cuz i got into a fight with my seat tube. It was rotating, and the clamp was maxed/touching,so decided some fool installed wrong one, long story short, a whole can of worms with that. Anyway, maybe i was large - large, and it didnt like it (not recomended anyway). Maybe I am going nuts.

rhm

I hate it when that happens.