I found this on IFI's site, on their FAQ forums for the transmissions -- Paul Copioli posted this:
What are the transmission bearing specs?
There are two types of bearings used in the transmission. Below is a list of the bearings and various supplier's part numbers:
1. 17mm I.D. x 35mm O.D. x 10mm thick deep groove ball bearing.
- SKF part # 6003-2Z (with shields)
- TIMKEN (FAFNIR) part # 9103KDD (with shields)
2. 9mm I.D. x 26mm O.D. x 8mm thick deep groove ball bearing.
- SKF part # 629-2Z (with shields)
- TIMKEN (FAFNIR) part # 39KDD (with shields)
Please reference pages 1-6 and 5-3 in the "2005 FIRST Robotics Competition Kit Transmission Manual."
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