Increase the web and surface areas around the bearings to the largest available size that will fit. And the units are only five pounds heavier than stock. With removal of transmission bolts the replacement of any or all gears, drum or shaft is easily done. Any transmission available for the original cases will fit in these cases. Separate oil reservoir facilitates the use of any type of gear lubrication.
Transmission has inspection cover for easy visual access to the gearing.
The lower cover plate enables removal of all shift forks. Enough room between the engine and the transmission for a fuel pump and oil pump or vacuum pump. Being modular, either the engine or transmission could be removed separately, then either repaired or replaced so you get on with racing. With the Pro 1 cases the engine can be replaced in most situations within fifteen minutes and the transmission can be taken apart and repaired or replaced in about twenty five minutes. Another advantage is you can build a spare engine and save money by still using your original Pro 1 transmission cases.