BBSHD 74V With External Controller Upgrade
I had the BBS02 for a few months, and it was a great motor but after a while it just left me longing for more power. So I picked up a BBSHD, and was expecting a huge upgrade but much to my dismay, it barely topped out at 30mph, slower than my BBS02 actually. Torque was improved but only slightly, I let my girlfriend ride it and she said it was barely any faster.
The stock BBSHD stock internal controller is limited to 60V and 30A, which is quite pathetic. Even if your running a 52V pack, you will only get 1500W out of the motor, if that. I also upgraded to a 30T front sprocket and that upped the torque and raised the RPM's.
The motor felt more responsive and has more torque to push through tough terrain. @48V I managed to hit 28mph which a 3mph loss in top speed compared to the 46T front sprocket. The 30T front sprocket is ideal for off-road riding and trail riding. However, you will not be able to pedal as the motor will be spinning too fast and will be geared low.
At that point, I was still left longer for more power. So I took apart my BBSHD, removing the original controller and putting it to the side. I tested the Cyclone 36-72V 12FET controller, and it ran great however it was very noiser since the Cyclone Controller is square wave, also power delivery would be abrupt at times, again because it's a square wave controller.
Ultimately, I settled on a 18 Fet Sinewave Controller, and I have 12 FET Sinewave Controllers on the way for testing, and eventually for sale through my site.
Compared to the Cyclone Controller, the Sinewave Controller allows the motor to run much quieter, similar noise level as the stock controller. Throttle response is also much smoother than the Cyclone Controller, which could be abrupt at times. However, the greatest advantage is that the Sinewave Controller can be ran at 74V which significantly increases the RPM's of the BBSHD, which increases overall power, torque and speed.
On 48V the BBSHD simply runs out of breath way too quickly and power drop offs dramatically after hitting maximum speed in each gear. DC Electric Motors have a certain kV which is RPM per volt, the higher the voltage, the higher the RPM's. Therefore by moving to 74V the power band shifts up dramatically, you can extend the usefulness of each gear before having to change up. Its moving up to a 600cc from a 250cc motorcycle, you won't have to shift as often, and can essentially stay in one gear. The granny gear takes me to 18mph and can virtually obliterate any hill, as opposed to crawling up the hill on 48V.
If you want absolute power for your BBSHD, 74V is the way to go. The motor will spin significantly quicker than 52V and you will unlock the power of the BBSHD that is hidden away with the stock controller. It literally will transform your bike into a monster.