My wife and I have had our Pivot Shuttle SL's for about 3 months, needless to say we have had problems with the Fazua motors on one bike or the other the entire 3 months.
First my bike, brought it home from the LBS and it would not turn on, took it back the same day, Pivot picked the bike up and got it back to me in 3 days, turned out it was a bad battery.
Rode the bike 2 times after that, ran the battery pretty low, after charging the bike it would not turn on again, took it back to the shop, Pivot rep came to the shop and said it needed an update, I guess when the battery went below 10% it shut it down for protection, I guess the update took that function out now.
Bike is now working but when peddling uphill the motor is shutting on and off up the entire hill, I thought to myself I thought this bike was supposed to help me up the hills, lol. It stayed that way the entire ride, so now we head out this last Sat, got 300 yards into the ride and a flashing RED LED appears, tried resetting several times but would not reset, went ahead and rode a shortened ride of 6 miles with no assist, currently the bike is at the shop wainting for an answer on what's wrong, very frustrating.
My Wifes bike
We bought this bike for her specifically for a trip to Moab she was planning with her girlfriend, everything went fine the first day no issues, the second day she gets 7 miles into her ride and the LED light starts flashing RED (Which is a Hard Fault), she rides the rest of the ride with no assist, she calls me when she gets back and I tell her how to do a Reset (Hold switch in the off position for 10 seconds) she does this and the bike starts working again.
3rd day in the first mile the LED light starts flashing Red again, she does the reset and it starts working again, worked fine the rest of the trip.
Now she is back home, first ride after she is home the LED light flashes Red again, tries the reset and it will not work, when she got home I tried it several times but no luck, took it into the shop, I guess they pulled the wires out and did some switching of the wires and did a reset that way, I believe someone posted on here the instructions to do that, we got the bike back and it has now worked well the last 2 times out.
Mode switch on this bike is junk, mine will not work unless I use 2 hands on it, my wife's sticks in the on position as well, supposably Fazua is sending 2 new ones, I hope it's an upgrade.
Sorry for the long read, let me know if any of you have had the issue with the motor shutting on and off while peddling, Fazua has a third-party answer their questions and have had complaints about that and hopes there will be a fix in the next update which they say will be this week.
By the way I love how this bike handles, it is crazy fast downhill, just wish I had a little more help uphill.