eCumbent Bike - MAC Motor 8T - New Controller options

[drummerian]

Some years ago (2103!) I purchased a MAC motor kit from Paul over at em3ev to put in to a home built, high(ish) performance, recumbent trike. Going back though my communications with him at the time, what a patient a knoweldgable chap! Unfortunately life got in the way, my interests moved to some other exciting motor based things and my project got sidelined somewhat.

I have since built a few ebikes for myself and friends using fairly generic hub motors, KT controllers, and perhaps my favourite, the KT LCD4 compact displays. None of these are particually performance machines but they have had plenty of miles put on them, including my home built cargo bike which regularly is loaded up with the weekly shop. I've been impressed with these cheap bits, they just seem to work and now I have nailed fitting PAS to external BB's i've been really happy using it, it also keeps things that bit more legit, even if sometimes some speed limitations are lifted a little...

I have recently purchased a recumbent bike (a Speedmachine GT for reference), I'd like to turn this in to a fast commuter bike. Today I popped my old MAC parts on and had a great time wizzing up and down however, it feels like things have moved on a bit, my requirements have changed a bit and it's time to work out what's the best setup for a modern MAC.
Perhaps some new requirements to discuss:

• PAS - I like it on my other bikes. I like to pedal when I ride a bike. I like a throttle for pullaway purposes and have found this works perfectly on the cargo bike (heavy) and the recumbent (awkward) to just get up to 5mph or so for stability.
  • The current controller I have doesn't have PAS input at all. I know at the time I looked at using a CA for this but I'd like to avoid this if I can.
• Small display with settings for assist levels. Again, I like how bikes ride with this, I can dial in assist as I need. I could go torque sensing but I don't really want the cost/complication of this. The KT LCD4 has severed me well on other builds
  • Again, apart from a CA I don't believe my current controller supports a display.
• 20-25mph cruise is absolutely fine. The MAC in it's current configuration will get just about 30mph, I am hoping that with a new pack dropping the voltage down i'll still end up with the performance I want.
  • I'd like to replace the Lipo battery mess that I've made with a proper pack. This will likely take the form of a 48V/52V pack, I already have some 21700cells to use for this and the ability to weld them in to a configuration that works with a shark shell or something like this.

I know there are some posts about MAC motors with weird hall placements and avoiding a new controller as a result if possible. There are some cool looking self learning and opensource controllers out there, to be honest this is really just the beginnings of my research!

For reference the bits I have already are (I think, struggling to find full details):
Mac Rear 500/1000W Pick'n'Mix Kit - Controller Type 12 fet 40A (36-72V, IRFB4110)
- Motor Speed 320rpm loaded @36V 8T
- Upgrade/Standard Motor Upgraded Phase Incl. Temp Sens
- Wheel Type 26" Alex DH19 Disc
- 15S2P LIPO setup (63v).

Any comments are appreciated! Thanks all

 

[drummerian]

Oh, also forgot to mention, the current controller is pretty bulky! I'd love something a bit more compact that can integrate in to the build a little easier.

 

[Epithemeus]

If willing to splurge you could get basically the super harness kit from ebikes.ca sans motor https://ebikes.ca/shop/kits-by-type/superh-kits/gmac-superh-kit.html
The controller is tiny and fits into the battery casing. It also is designed with MAC motors in mind as they sell the GMAC which is the same motor, should even have presets for the firmware available instead of using the self learn.
With the super harness kit you don't have to use a CA and can choose a few small options for display.
With the clip on PAS sensors they sell it's pretty to add on usually with basically no trouble.

 

[neptronix]

For exceptionally good PAS is what you need, and 25mph is the top speed, you probably want a baserunner from ebikes.ca. It supports a gazillion PAS options.

The one good thing about your existing controller is that it's designed to handle the very high RPM of the MAC.. this allows the MAC to operate at >30mph without stuttering and weird effects.

Below that speed, practically any controller should work.
I'm pretty sure that infineon clone controller supports oldschool magnet ring based PAS, but the leads are not wired.

 

[drummerian]

Wow, amazing responses already! I'll take a look, that baserunner certainly looks tidy, I might have to keep my eye out on the classifieds to try and bring this build in to some kind of budget I can get my head around

 

[drummerian]

As nice as the phaserunner and baserunner options look they aren't cheap! I was hoping since I wasn't requiring such high performance that there may be some cheaper bits available that will still provide some smooth reliable running in the setup I'm after?

 

[neptronix]

Yeah they aren't, they're primo controllers... any feature you could ask for - they have it.

Here's some info on adding PAS to your existing controller:
Adding PAS to EM3EV controller

You will probably need to program it to enable the feature though. Do you have a programming cable?

I don't know of any other controllers that support torque sensing PAS.

 

[drummerian]

I do have a programming cable somewhere for it yes

I'm not too fussed by torque sensing pas, just pedal movement PAS

Thanks so much for the help!

 

[drummerian]

If I did look at the baserunner should I be considering the Hailong or the Reention batteries? Again there seems to be some info floating around online about whether these have remained compatible with available controllers?

 

[neptronix]

You don't need to switch your battery but it is an option to fit the controller into the battery case. I dunno the specifics as i have a phaserunner.

 

[drummerian]

I'm planning to switch the battery anyway to be honest, the 15s Lipos I have from 10 years ago are functional but things have moved on a bit and I think i'll move towards 21700's

 

[neptronix]

The sad thing is that lipos haven't moved on. We can buy 290whr/kg 21700's today, but the best lipo i've seen is somewhere around 170whr/kg.

I remember 20AH 46v filling out my biggest triangle bag. Now i have a 52v 19.5ah battery with 21700's that consumes 70% of that space despite the volumetrically inefficient packaging of round cells vs pouch cells. And less weight. Good times!

 

[drummerian]

Are you aware of 21700 cell packs that still support the base mounted controllers? I have some cells that I can use for a build so that's my area of research

 

[neptronix]

ebikes.ca sells tons of them. Including the cases.
em3ev uses similar cases and may be compatible.

If you are pushing any kind of power i would consider running the controller outside of the case for best heat dispersion. ebikes.ca sells a few mounts.

 

[drummerian]

Thanks

Ill run some numbers but I'm hoping that my mission profile will be low enough average power that I can get away with hiding the controller away in the battery base

 

[Epithemeus]

If you get the battery from anywhere but ebikes.ca you'll need to buy a custom baseplate from them for fitting the baserunner. Reention battery baseplate, machined to fit Baserunner (a bit more info here Baserunner - Grin Products - Product Info)
Unless you have the ability to machine down the heatsink yourself.

 

[drummerian]

If you get the battery from anywhere but ebikes.ca you'll need to buy a custom baseplate from them for fitting the baserunner. Reention battery baseplate, machined to fit Baserunner (a bit more info here Baserunner - Grin Products - Product Info)
Unless you have the ability to machine down the heatsink yourself.

Thanks, do you have any advice on whether I should look at the Reention vs Hailong? Looks like there are 21700 options in both, not sure if either is more highly rated at all?

 

[Epithemeus]

Thanks, do you have any advice on whether I should look at the Reention vs Hailong? Looks like there are 21700 options in both, not sure if either is more highly rated at all?

Nah, I've only used a reention case myself but from what I've read the two are very similar and neither is superior. Focus more on the quality of the cells inside instead of the shell on the outside (just in case there's confusion, reention and hailong are the brand/style of the battery case, not the battery itself. Any brand of battery cells can be put in either)

 

[drummerian]

Nah, I've only used a reention case myself but from what I've read the two are very similar and neither is superior. Focus more on the quality of the cells inside instead of the shell on the outside (just in case there's confusion, reention and hailong are the brand/style of the battery case, not the battery itself. Any brand of battery cells can be put in either)

Thanks so much.

Not to worry about cells/understanding of the casing. The reason I was asking is that I already have a selection of 21700 cells waiting to go in to a pack, just wasn't sure which shell to choose. Just got to find suppliers that'll ship to the UK now and work out which size to go for.