I have been reading this thread since the link was posted on the e-bikes.ca home page what feels like years ago. I contacted Grin about this and did not get an answer I liked so I'm going to post here in hopes of getting a better answer.
I have an application that the customer wants a minimum input wattage from the rider and upon sustaining that wattage will cruise at a set speed. The numbers currently being bandied about are 100W to maintain 20 MPH. I have been putting the numbers through the simulator and this will result in a significant boost to assisted range, to about 100 miles with a 36V20Ah Ping pack in no wind dead flat conditions (riding inside on a large velodrome). Real world numbers would be a lot less, but still for most people this would be a bike they could ride all week to work with maybe one charge a week. Justin gave me a workaround that would require the user to reset the zero point for the Thun while holding a known force on the left pedal and use t*rpm*(constant) to have the required power for turning on the motor and getting the cruise control active. This won't work for 2 reasons:
1) Not knowing precisely how much force is being applied to the left pedal while the zero is being reset.
2) It requires user input for calibration when the user may just want to ride along without putting any power into the pedals at all.
Thus my conundrum. Justin already told me how to set the cruise control to a lower speed by using a throttle on the Aux input so the rider will still get assist when the input power levels are met, just at a lower speed as conditions dictate. (Imagine that, someone might want to ride slower
than all out
The bike is a 'bent that will be using the 2805 9C and a 20" front wheel, with the 35A controller and the aforementioned Ping pack. Without the assist pieces it weighs in just under 30 pounds ready to fly. I have done a test with the bike running the same gear as the assist model would use and the bike ballasted to 50 pounds (roughly the weight of the bike with all the assist pieces in place) and took it for a 8 mile ride through the neighborhood and too a local grocery store (not the store i usually use, the next store over) and discovered that you REALLY don't want to let the charge run out on this bike even without any cogging resistance from the motor, hence the immediate choice to install the CA and find a PAS controller so that customers will still have decent legs when the battery runs out. Then I saw the CAV3 and our worries were over (we thought). I still think that the CAV3 will be the solution to this problem, just not with the firmware as it exists. Of course if someone has a better idea, I'm all ears.