Three years strong and I don't think we'll go to anything else....at least not in the near future. The concern Sanddrag has expressed about shaft wear and such is NOT a problem at all. We do measure sizes before and after season when looking at what we could improve and we have not discovered wear. This is simply because we harden the pieces we need to and keep a good amount of lubrication. So rather than posting something you DON'T know about from experience, maybe you should let the people who have built these talk about the down sides. I don't mean to start a fight with anyone, but I just can't understand how people who have not used these transmissions can discuss any problems with them.
The biggest negative we've seen is these transmissions take time to machine with our team capabilities. You can make them with just a lathe and a mill. They are that simple, but having access to a wire EDM or a water jet would greatly help reduce the amount of machine time.
Great to see 948 investigating this design. Hope to see it on your robot this season! Good luck
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