Yes, we now have 3 eBikes in the stable, full time..
Early on, when i was just starting out with this eBike business, i picked up a $500 used "ecoBike elegance" for my lady. She'd not been into bike riding for a while and i wanted to really reduce our gas usage by going to the store together.
Now this was fine and dandy, but when i got my MAC and fell in love with it, the 250w ecobike just couldn't keep up.
I figured we could have made $ selling it ( got a great deal on it ), rather than upgrading it, so we did.. and we made $150 on the deal.
Plans for a higher power bike for her, that could keep up with my 8T MAC fairly well, ensued in record time.
We picked up a green Trek we found on craigslist ( $90 and just needed a little tune up! ) and later ordered the 350w MAC motor in a 700c wheel.
The 350w MAC motor appears to come in one wind, sorta a 9T equivalent to the rear, and does 22-24mph on a 700c wheel. It's a pound lighter than the 500w MAC, but not smaller. It seems to handle a pretty good level of power constant without getting warm ( around 500w average, with peaks of 24A / ~1000w ).
Initially, ampedbike torque arms were ordered mistakenly. They were very loose on the motor and would have been useless. So i set to making some torque plates.
Took me a very long time to make them. I have really wimpy tools. A local friend ( tom tom on ES ) let me use his angle grinder to cut the basic shape.. the rest was all $$$ dremel bits, and sanding by hand.
Luckily the fork is steel, so i didn't have to make the plates super strong. But i kinda overkilled them anyway.. why not
So here is the ( mostly ) finished product! the batteries and controller hang out in the rear topeak bag.
.. which is of course Lipo.. see the 4mm bullet connector at the end of the 9FET controller
We can fit about 14 5S or 6S 5AH packs in it, but often we just stick in a 10AH/10S brick.
Controller is set to pull a maximum of 24A, and the phase amps are set to 2.0x that value. It doesn't pull too hard from a stop, it really forces you to pedal along initially, then picks up speed in the mid-range. Downside is that it's rather anemic on hills or in a head wind. I will up the amps a little when i know 100% that the torque plates are doing their job.
So far, so good! it's quite a bit more efficient than my 8T mac on 36A/36V due to the lower speed and the fact that it kinda forces you into putting more pedal effort in. This bike is exactly what i had in mind when i set off to build my first eBike ( the 250w was just a dog on 36v and the top speed of 18mph sucked! ) - more like a bicycle than a slow motorcycle. The top speed of about 23mph is really bicycle like.
The 350W MAC motor is a little spendy for a first time bike build, but i'd say it's worth it if you want pedal assist and just a wee bit more speed than you'd normally be able to muster on a nonpowered bike. The weight of the motor could be cut down a little, but it's not too bad at 9lbs.