Had a new experience last night renting a bike if this helps others. So, the only IGH that are known to be able to handle the torque of the G510 are Rohloff and Kindernay.. and Enviolo (but the spec sheet won't tell you that). Other hubs have failed in various tests. However, given the sensitivity of SA and Shimano hubs to shifting under load (and design of the load dogs in some hubs), I want to say this is probably due mostly to user error (I say that as a mech). I mean that, if there's an error in load application, or a spike in load, yes these drives are more prone to fail. If you're careful, you can still get thousands of miles out of them.
Anyway, I rode this Enviolo. Previously hated the hub for two reasons: (1) you can feel the loss of efficiency (87%?), and (2) the grip shift design (which is ALL they have) sucks! The reason why it sucks is well, grip shifts number one. It fucks up your position on the bar while you shift, reducing your power output. The more specific thing though, is that there is always play in the system. You have to be very careful shifting in one direction (which is not easy when you're cranking on a bike) to get to the gear ratio you need. The range is so compressed on the shifter, that you easily switch past your desired ratio. It's like trying to pick up rice with chop sticks while you're cranking at full power.
So yeah, these are the actual reasons why Enviolo won't ever be on race bikes. That and the weight, no way.. lol..
However, the thing can take torque. Way more torque than any other IGH technically, because you are only limited by the heat capacity of the internal transmission fluid. I don't know what this limit is, but it's significantly higher than what is listed on the Fallbrook website. The other thing is they are adding this system called 'Automatiq' to the hub now, which uses a servo connected by bluetooth to control the gearing ratio. If this system works precisely, that solves the above problems. So, with Enviolo I would say that 'Automatiq' is technically a base level solution to their engineering failures, and not an 'add-on' in any regard. Can't say that publicly though! People crack me up..
Anyway, I'm thinking about modding an existing G510 bike now with building a wheel around this system and installing Gates with a belt snubber. Rear triangle can be modified and it would be a fun project. This opens up the range for a ton more bikes to be considered, and allows me to build that ultimate commuter at a fraction of the cost, with more features than the R&M. Gotta get that throttle.. lol..
So, I'd add that in my experience Enviolo is pretty theoretically awesome with a motor drive and the auto servo installed. Changes the way this system feels on a bike. Unsprung mass is an issue, so yeah, these things will never be on racing bikes, but as this system evolves and is applied in this manner, the public approval will greatly increase for it. Just my $0.02..
