Metric Mechanic - Ultimate Transmission - Part 1

Stating the Problem
Rather than just "rebuilding", we have actually "re-engineered" the BMW manual transmission. BMW transmissions are quite strong for the most part but they do have two weak areas:

1. Layshaft bearing failures
2. Short synchronizer life

We re-engineered the synchonizer assembly for improved clutching action (a synchronizer is a form of a clutch) and we've greatly extended the wear limit of the synchronizer. This allows our transmissions to be shifted more aggressively without the fear of premature synchronizer failure. To cure layshaft bearing failures, we've substituted tapered roller bearings for the ball and/or flat roller bearings used in new and rebuilt gearboxes. Tapered roller bearings are the absolute best bearings to complement the Ultimate Transmission philosophy. When a layshaft bearing fails it can become quite serious. The bearing can come apart and quickly destroy the transmission. Synchronizer failures make the transmission miserable to shift. In solving these two problems we have produced a very strong, long lasting transmission.

History
The Ultimate Transmission was born in 1979 out of our autocrossing experience. We were a three to four man racing team involved in approximately 25 races per season over a 5 year period. In the beginning, our transmissions lasted an average of 2 to 3 races before the synchronizes would crunch. Yes, we were shifting extremely hard. We decided NOT to give up on our shifting style but instead to FIX THE SYNCHRONIZERS so that they could take the abuse. Enter an improved BMW transmission! At the end of our autocrossing career, after 465 races, the new gearbox still wouldn't miss a gear - no matter how hard we shifted it. In 1980, we began selling the gearbox locally to other autocrossers and street drivers who also began shifting them much harder. Thanks to this "testing" we found that the new demands now imposed on the gearbox eventually led to premature layshaft bearing failure. So, two years later, we found a FIX FOR THE BEARINGS as well. Enter the "Ultimate Transmission" with redesigned synchronizers for improved shifting and tapered roller bearings to support the layshaft!