![]() This is something they can measure at the shop. 020" clearance when the carrier is compressed by tightening the pin and nut with moderate torque. Bring the pin and pin nut, and tools with you so they can get it just right. The machinist should be able to figure out the correct displacement. I found that 1.95" worked for me, but manufacturing differences may mean it's different in your case. Meaning, it can't be too wide or it will bind. Critical: the bushing width needs to take into account the deflection of the bottom bracket carrier when tightened. Ask them to fit the bearings into the swing arm by milling it out and creating the bushing. Bring the fully disassembled swing arm, the bearings, and the bottom bracket carrier with you. Any competent machine shop can do this for you. The next step is to fit the new bearings into the swing arm housing which requires a milling operation and the creation of a bushing. These can be bought on Amazon: Koyo B-1816 Needle Roller Bearing, Full Complement Drawn Cup, Open, Inch, 1-1/8" ID, 1-3/8" OD, 1" Width. We will start by replacing the floating roller bearing design with two encased needle bearings that fit perfectly, fully supporting the pivot pin. To repair the problem permanently requires a redesign. It carriers the brunt of the pedaling forces. Typically, the problem pivot (there are two) is the one closest to the bottom bracket. ![]() Of course, once the swing arm aluminum is worn it will never be right again. ![]() It's just too weak of a design to last under even normal use. A heavy or aggressive rider will wear it out very quickly allowing a slight movement during pedaling which translates into a pronounced creak or click that can be felt in the pedals. It works well until the steel of the bearing wears the aluminum on both sides. They use an off-the-shelf 1-1/8" roller bearing from a headset that is suspended between an aluminum split cone washer and the beveled interior shoulder of the swing arm housing. However, its fatal flaw is the eventual wear of the aluminum to steel connections in their floating bearing design. The parallelogram design of GT's complex iDrive 4 rear suspension pivot is clever and effective at stopping pedal bob, especially while climbing in the saddle. ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |