Amped Bikes brushless front hub kit speed controller upgrade questions
I just installed an Ampedbikes brushless front hub motor kit on my beach cruiser. It runs smoothly, but takes a bit to get up to speed. Does anyone have any experience with these kits and could someone recommend a good durable controller upgrade to increase my speed. I am running one of their 36v 12ah tube batteries. The controller that came with the kit is rated at 25 amps I believe. I would like to know also if upgrading to a better, higher rated controller would damage the motor. Any input is appreciated. Thanks.
From simulations I have done, a higher current controller doesn't help much getting you up to speed, as the current limitation only kicks in at really low speeds.
Well the motor would probably be ok, but the battery may not like higher discharges (currently 25amps is about 2C max)
That battery may sag under say 3C.
What Im saying is you may need to upgrade the battery too, or the voltage sag under 3C may counteract the increased current.
The cheapest and simplest way to get a small boost would be to put one Headway Lifepo4 cell in series with your batt. Your controller should be able to handle 3.3 extra volts. Headway now do 16amphr cyclindrical cell, could easily mount it on the bike frame. That with a single cell charger will cost you about $40.
The fact its 16amphr is good because it wont run down before your main pack does. Just charge the extra cell when you charge the main batt
I put a single auxilliary cell boost on my scooter, made quite an improvement.
BTW, how fast do you want a FWD kit to accelerate? High power and FWD generally don't mix. Be careful what you wish for. I've found both the direct drive and the geared kits from AMPED to have adequate acceleration. Check for low air pressure and brake drag as no cost improvements. Running a narrower, smooth tread higher pressure tire can add to range and pickup as well if they meet your needs for ride quality, traction and rim protection. If you're running SLAs over your rear rack (as opposed to your very nice, light, centrally located tube battery, the fatter tire will be a better choice for rim protection and ride quality.