OK, converted one of batteries back to 48volts and taken my bike out for a spin. My bike is a Yeti 575 full suspension bike on 27.5 wheels and I ride steepish single track around my area.
Fitting the bike out with the kit is doddle with a small caveat. The full suspension bikes cannot take the rear support bracket to prevent the motor spinning and you will have to be a bit more creative. My BB is 73mm anyway so the 5mm spacers that come with the kit to fit between the outer motor bracket and engine are 5mm short. I opted for a small 5mm section of Ali from the front screw up to the frame to prevent any rotation and I also indented that outer bracket to mimic the Bafung system. I made a 10mm spacer for the rear screw. Do torque up the retaining nut for the motor spindle to at least 40Nm as this probably on its own will retain the engine and prevent any rotation, but perhaps do put on a anti rotation strap if you can.
The motor shape really means that you cannot move it up and forwards like the Bafung and you end up with it hung under the bike. I had my doubts about this but if you think it through, going over logs and the likes, the clearance is always limited by the largest crank ring, will you ever clout that under part of the BB, probably not. You do need to get your head around this a bit, it looks wrong but in use I doubt it will be a problem. The motor unit is quite a bit smaller than than the Bafung unit anyway so seems to fit and tuck up under the BB. Its just visually we are not used to this. The downside in sitting the unit underneath though is the cables are quite exposed to mud and water off the back tyre, I hope there's good waterproofing in the case.
Fit out to the bike is just so simple that most could do it, but anyone who says they have done it in a couple of hours are being a bit optimistic. In reality by the time you actually strip the bits off the bike, get the unit on and fitted after thinking it through a bit and have a coffee, a talk to the missus and then have doubts that you are doing the right thing, then set up the gears and the chain line, fit the battery, change the battery connections etc, it'll take a day. It is a very easy kit to fit though. I have to say the chain line isn't great ( 3rd ring on mine ) but you can get around this by fitting a 150mm rear cassette and stretching the rear triangle a little. On the 3rd ring on my 10 speed seems to work fine and although I suspect the chain is really at its limits, it seems to get onto the larger ring on the cassette OK.
Set up of the LCD display takes a bit of thought, hint wait until the full display screen is up and steady before holding down the two buttons for 3 seconds. The manual is not clear but once you get your head around it, its reasonably logical. The unit sits a long way forward and high up. I took the unit off its mount and reversed it so that mount faces back down the stem, the LCD sits lower and is more out of the way and easier to read.
OK spin it up and take it for a ride. My unit was really noisy at first compared to the Bafung, but now having done 40 miles on it, that seems to have quietened down a bit or I'm used to it. Its not offensive but you do know you have a very small electric engine on board. I do suspect though as the gears work out a " mesh " with each other that it will quieten down even more. On first rides this engine is very very good, really on a par with the Bosch system and the ride is very mtb like with a hint of assistance. In some ways better than I really expected to be honest. It is definitely not anywhere as grunty as the Bafung 750W but you have 10spds at the back and you just need to use the gears a bit more, the power is more than enough for the single track I do and probably in reality the 36volt units could be enough.
I was very worried about the reported cadence speeds of the 36 volts, the 48 volt units are actually pretty good and although I don't have a cadence meter on board, there's not much difference between my normal cadence and on this unit. At the very top end of my own cadence I can feel that you do start working against the motor, I found simply by changing down 1 gear puts you back into the motor sweet spot. That's telling me its not far out ( now if we could have used 52volts ). Bit of a bonus there and my worries about 52volts to up the cadence was probably somewhat unwarranted.
I think my set up 42T at the front and 36T at the back on a 27.5 rim is just slightly wrong for the steepest of single track I do. The Bafung being that bit more powerful will pull this set up but this unit won't. Its easy enough to fit a stock 36t ring or perhaps get a 42T rear climb ring perhaps, I'll see what I've got in the stock of bits I've taken off other bikes and see what I can come up with. The top speed is never going to much above 25mph anyway so maybe its just easiest to go to a 36T front ring. I know some have fitted dual front rings but then things get a bit complicated as far as chain line goes.
In summary then, this is a really cool bit of kit, if its reliability is anything like the Bafung and you are more interested in getting a feeling of riding a bike rather than a small petrol motor bike, then Bafung have a real competitor. I guess as more of us fit them and knowledge begins to build up as to how to hack the firmware, then one can only be impressed thus far.
