Earlier this fall I started a thread about how to replace the bottom bracket on a 1990 Trek 1400. Thanks to everyone’s help I was able to complete this simple project quite easily. http://www.bikeforums.net/showthread...ent?highlight= I ended up just disassembling the BB, cleaning everything, replaced the bearings (used loose ball bearings rather than cages but I did add the extra ball bearings), relubed with Marine grade waterproof grease and reassembled. Played with it a little to make sure there was no play in the cranks, but was not so tight as to drag and I was done. ….or so I thought.
The bike sat for a while until I decided to ride it again a few days ago. Much to my dismay, the front derailleur now no longer shifts onto the top ring. The chain just jams between the top ring and the derailleur cage. The chain never catches on to the teeth of the top ring. Would anyone have any clues as to why this happening and what the solution might be?
During the servicing of the bottom bracket I did not mess with anything else on the bike. The front derailleur is installed at the correct angle and the correct height. The derailleur cable and set screws are set correctly. If I manually move the chain on to the top ring, it shifts down to lower ring correctly. And naturally it all worked correctly before I serviced the BB. I just can’t get the chain to shift to the top ring without jamming against the top ring.
My initial thought was maybe the chain line is not correct because the axle is asymmetrical. I have attached the data sheet for the bottom bracket: IMG_0003.jpgIMG_0004.jpg This looks to me that the axle is symmetrical. Correct? Could I have possibly put in the wrong sized bearings? Could the crank arms be either not tight enough or tightened down too far on the spindle? Does anyone have any clues where I may have messed up?
Thanks for any help you can give me,