Saturday, January 24, 2015

Sturdy rear rack

This rack came up for sale on

I grabbed it for the very sturdy design and build quality. It needs a custom bracket to attach it to my bikes but that's not very difficult to fabricate. It's much thicker that standard racks and has a double shelf. If I use it with the black Tidalforce in electric bike, it would make it look very much like a cargo Bike!

Spring project controller (field-oriented controller)

 I picked up an field oriented controller (FOC) a few days ago. These are highly specialized, programmable controllers that offer complete control of motors both sensored or sensorless. The first and maybe only batch of these have sold out, unfortunately. These are no longer available from the OEM as an easily customized part. They are now encased in a resin case.

I hope to be able to put this to good use with the E+ motors that I have. The E+ motors are 3 phase motors that have integrated custom/proprietary controllers that require proprietary batteries. However, they should be able to be used as generic 3 phase ebike motors if the integrated controllers can be bypassed. This controller may even be used with the 7 phase Tidalforce motors but I'm not going to touch a beautiful motor/controller combination that is the Tidalforce system! 

The BAC500 is a field-oriented controller that uses sine-waves to feed power to the motor and so is much quieter than typical square-wave controllers. The buzz that you hear from your typical eBikes is usually the square-wave noise and the resultant noise generated by the motor windings. A FOC by definition automates the phase advance process so that the motor is driven at optimal timing even at very high RPMs.

The Tidalforce and E+ systems utilize sine-wave controllers so are extraordinarily quiet. In use, they are essentially completely silent.

The BAC500 is a tiny package with a custom CNC torpedo shaped case. It's slightly thicker than a Cycle Analyst.

Monday, November 17, 2014

Picture of Tidalforce M-750X electric bike with the Auxiliary Water Bottle Battery Pack

I took the bike outside to take some clear pictures of the Tidalforce M-750X electric bike with the auxiliary water bottle mounted battery. It looks really nice and clean. I need to do a few more things. Clean up the cables some more and to add a disc brake to the front fork so that it can work with the disc wheel! :)

Completed Tidalforce Electric Bike Bottle Mount Battery Pack

I spent a few minutes last week finishing up the Tidalforce Electric Bike Bottle Mount Battery Pack.

I wrapped the case with an acrylic outer shell and overwrapped it with some very wide gaffers tape. It looks very clean and matches the frame of the Tidalforce bike very well. It's highly water resistant and the acrylic protects the cells inside.

With the battery mounted near the middle of the bike, the balance is greatly improved over a rear rack mounted pack. Also, the bike feels so much lighter to move around. I haven't measured it yet, but it has to be at least 25 lbs lighter than with the front hub battery.

Saturday, November 8, 2014

Progress on bottle mount battery for my Tidalforce electric bike

I worked on the bottle mount battery tonight. I bought some acrylic and gaffers tape and created a shell/case for the somewhat delicate LIPO battery. The battery does not have a protective case so I created one. I need to put a top on it and seal it from the elements, however, it's very stable and looks very solid. I used 3 3M Velstraps.

Friday, October 10, 2014

Water Bottle Battery Mount for the Tidalforce M-750X electric bike

I've been agonizing for quite a while on how to best place a 3rd party battery pack on the Tidalforce M-750 or M-750X frame. Having a rear rack is challenging since the bike folds and using a beam rack seems unreliable since the weight on a beam would naturally want to move off axis (swing left or right).

Mounting it on the front of the bike isn't practical either, however, with a front rack, it might be easier.

I finally happened upon perhaps an ideal placement for a small 3rd party LiPO pack. Right on the water bottle mounts!

I bought an adjustable water bottle cage and tried mounting the LiPO pack to it. It seems to work quite well. The weather hasn't been cooperating and I haven't had a chance to ride it yet, however, I'm very hopeful that it will work out well.

This obviously won't be the final packaging of the battery, however, It did look snug and held tight with just Gorilla duct tape.

Battery Choices

I recently picked up a couple of batteries for my Tidalforce bikes. One of the huge advantages of having Tidalforce bikes is the ability to use 3rd party batteries. You are never stuck with the company's original battery when it's time to upgrade. You can use any decent battery that can support approximately a 30A draw. That isn't just any battery, but choices available at that rating are pretty wide.

I picked up a Headway LiFePO4 12.5Ah pack and also a 10Ah LiPO pack. Here's a comparison shot of the two side-by-side. The smaller one is the LiPO and the larger is the LiFePO4.

The LiPO pack is about 1/4 the size of the LiFePO4 pack, however, the LiFePO4 pack has a much longer life expectancy than the LiPO pack. The LiPO pack has the advantage of more even power output and much higher power density...