My DIY builds: GMAC, BBSHD, 9C RH212, CYC Photon, ToSeven DM01

Re: GMAC regen. Agree most will have no use for the regen. from a charging standpoint (mostly for folks riding in the hills). It was the regen. braking potential that had my interest. Are you planning on setting that up and using that to stop/slow the bike?
 
Hubsinks? I used them for my new 9C from Grin. Their controller and gear leaves most kit sellers in its dust.
I wonder if more folks investigate the use of regen whether we'll also see more use of heat managing/reducing items like hubsinks and Statorade? I mean, when will we give the motor's a break? You climb the hill and everything gets hot and now going down the other side with regen enabled the motor doesn't get it's usual opportunity to cool down.

I'm still looking forward to having a fused clutch option for popular smaller geared hub motors, so we can fairly easily play with locked or unlocked operations. I'm thinking of buying a spare gear/clutch assembly for one of my Shengyi motors just to play around with a locked clutch (and have a replacement set of gears).

Or perhaps for the best of both worlds (really dreaming here) we'll get a remotely controllable clutch assembly ... one that can be locked up via external command - ideally an electrical one.
 
Sadly regen gets more attention for charging then braking. And why I stick with Grin controllers. The braking on my. front hub bike is awesome. It’s a Lyen controller before I started Grinning.
 
I mean, when will we give the motor's a break? You climb the hill and everything gets hot and now going down the other side with regen enabled the motor doesn't get it's usual opportunity to cool down.
Contrary to many here a DD hub is very easily monitored and anything that reduces heat is a good thing.

What are the internal temps on Bafang motors after a steep climb?

Your motor temps?
 
Re: GMAC regen. Agree most will have no use for the regen. from a charging standpoint (mostly for folks riding in the hills). It was the regen. braking potential that had my interest. Are you planning on setting that up and using that to stop/slow the bike?
Yes, I am more interested in the braking than the charging. I will definately be setting that up soon. No idea on what the eventual outcome will be
 
Yes, I am more interested in the braking than the charging. I will definately be setting that up soon. No idea on what the eventual outcome will be
I first set the regen brakes to high on the CA3. Stopping power was AWESOME once a good setting tested OK.
 
when will we give the motor's a break? You climb the hill and everything gets hot and now going down the other side with regen enabled the motor doesn't get it's usual opportunity to cool down.

I don't think this is true. Regen braking should not be creating the kind of heat motor generates when climbing a steep hill.

Btw regen is nice but the real benefit is braking which is great.
 
I don't think this is true. Regen braking should not be creating the kind of heat motor generates when climbing a steep hill.

Btw regen is nice but the real benefit is braking which is great.
No, probably not the same amount of heat as going up but it's still adding some heat, where in the past when coasting downhill the motor was cooling off.

I agree, and we've generally been referring generically to regen as providing either or both functions (recharge voltage to the battery and an additional loading of the motor to provide a braking action).
 
Initial GMAC Regen Ride Report
I by no means claim to be a regen expert, just want to share my experiences playing with Regen on the new CA3 3.2 beta software. Most all of what I report here is simple physics when you think about what is going on but many might not have realized (like myself) how it might manifest itself in real life riding.

I do not have brake cutout switches or any desire to use them. I hate them on any ebike I have ridden.

I have both a 52v 13.5ah and 52V 17.0ah pack. I setup the Phaserunner to limit regen current to 7amps which limits regen power to about 350watts. I could go higher (up to 1C).

Regen if your pack is fully charged will not be effective if the phaserunner is setup to not overcharge the battery.

I setup my CA3 for both Backpedal Regen and Regen based off the AuxD input (what is used to change PAS levels).

I could never get Backpedal Regen to work either in position mode (the more you backpedal the more regen) or throttle mode (backpedal engages regen which can be modulated with throttle). The erider BB is a 1 wire setup which means that it cannot sense rotation direction so that is the likely explanation. I have an email to Grin to confirm.

The AuxD setup just allows negative assist levels (regen of course) and is very intuitive to use (although not convenient in all situations). It can be setup so it reset to the power on default assist level when coming to a complete stop which I have done. I initially setup 5 regen levels

Level 1 - only slightly noticable (and power (which is positive) in display seems the same as power when coasting)
Level 2-Level 5 - all levels are -350watts, the higher levels seem to reach 350watts quicker but Im not 100% sure on this. Braking at -350 watts is significant but not enough to lock the rear wheel. I got up to 30mph going downhill on a 6% grade and -350 watts took probably a football field to stop (AUW of rider an bike is around 300#).

So next step is to go to 10 regen levels to have more fidelity. I doubt I will up the Phaserunner regen max power as I dont see how I would need that much braking on a button. The button just seems more of a way to limit downhill coasting speed which seems about right at 350watts. We will see how I use it in the future

An interesting thing about negative assist levels, you can theoretically charge your bike if you pedal with negative assist although its not fun (I tried it).

Simple stats from todays ride:
21.7 miles, 15.6mph average speed, 1250ft elevation.
7.1% regen at .52ah regen ( I used it alot, probably not more than 3% on typical rides)

Really bummed about the lack of backpedal regen👎

An interesting thing I tried was 350watts regen and just throttle use. Obviously, the throttle signal overrides the regen but it re-engages when your off the throttle so you have something similar to 1 pedal driving in electric cars.
 
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Sounds like it's going to be quite a learning curve - so many options?
 
GMAC Regen Ride Report Update
Grin confirmed that the Erider BB and its single wire doesnt work with backpedaling so no backpedaling regen.

I might try to figure out where to put a simple button on my handlebars to use instead of a brake switch (perhaps inline with a brake switch which might be safer due to muscle memory in a panic stop situation...I always have to use the rear brake lever, the button is extra for motor cutout/regen). I have several handlebar buttons laying around but no room on my handlebars and I am a handlebar minimalist.

Did a ride today with up to 9 regen levels(max allowed, was 5 last time) on the AuxD (pas level switches) with grades up to 10%.

Battery used today was charged to a higher voltage so regen power is a tad different.

Regen level(-1) - I feel a slight drag but power is the same as no assist. Speed seems unchanged
Regen level(-2)- seems to generate about -100W, good for mild speed check
Regen level(-3 to -9) - all are -400W (higher than last time due to higher battery voltage). The 400W is determined by the max regen current of 7A set in the phaserunner

I havnt tested the Regen(-2) much in this ride, mostly Regen(-3).

Coming down a section of paved road between 8-10% where I can reach peak speeds of around 40mph(I typically brake check it to 30mph). With Regen(-3), it stayed at a constant 24mph and -400W. Motor temps didnt seem to increase much if any that I could tell (63-64c). It was about 65F during this ride.

I think the CA needs a max regen parameter in percent(based on the philosophy of how it all seems to work). Currently the way it works is that the phaserunner is set to the max regen current but the CA (using the AuxD) independently of the phaserunner only has the number of levels (limited to 9) which makes regen steps = 100%/number of levels. For my situation, the regen steps are to big. I will send a request to Grin for this. Hopefully this makes sense. Basically the 100%/number of levels needs to be configurable%/number of levels.

Update:
There is a Max Regen Phase Current(defaults to 90A) in Phaserunner setup which is different thant the Max Battery Regen Current. Pretty sure this is how I would control the max regen mentioned above. WIll provide a ride report/update when I try this.
 
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GMAC Regen Ride Report Update
The Max Regen Phase Current(defaults to 90A) in Phaserunner setup didnt seem to have as effect at the regen levels I am using (they must be way below). Lowering it to 50A didnt have any effect on the regen level vs power.

The phaserunner does regen based off throttle out voltage from the CA. The Phaserunner Suite default is 0.85V to start regen with max regen at 0.0V. I had it set to 0.85V to 0.2V so changing the lower value to 0.0 should give more fidelity for each AuxD negative PAS level. To taylor AuxD regen levels vs actual regen seem to be a combo of the number of CA AuxD regen steps (0-9, 0 is deactivated), Phaserunner Max Regen Phase Current, Phaserunner Max Regen Battery Current, Phaserunner Brake(Regen) start voltage(the higher value) and Phaserunner Brake(Regen) Max voltage(the lower value).

Overall, I think I will use braking/regen more than I thought. Im going to figure out how to have a dedicated switch to activate and use throttle to modulate. A perfect solution would be to have a proportional brake lever and I could just ditch the rear brake. I cant even imagine what 90A of regen braking would be like

Still bummed about the lack of backpedal regen with the erider Torque sensing handlebar. A great use for backpedal regen would be when I have my hands on the center part of my handlebars
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A second throttle, on the opposite side of the handlebars, for proportional regen signal?

I like the idea of setting something up with the LH brake handle too....

What are Grin's thoughts here? What are they suggesting?
 
A second throttle, on the opposite side of the handlebars, for proportional regen signal?

I like the idea of setting something up with the LH brake handle too....

What are Grin's thoughts here? What are they suggesting?
 
A perfect solution would be to have a proportional brake lever and I could just ditch the rear brake. I cant even imagine what 90A of regen braking would be like
I agree, a proportional brake lever would make a lot of sense. They have been discussed for a few years now, I'm surprised that a reasonable ebike oriented one (small, simple, waterproof, etc.) hasn't shown up. I think having regen capabilities in a number of popular controllers combined with a proportional lever would open up the advantages of regen for a lot of people. Unfortunately as can be seen from Grin's setup with the CA there is no real popular consensus on how regen should be implemented.
 
GMAC repair update
Kudos to Grin for the great and responsive service. They got the motor this morning and have already fixed it.
It had seized bearings on the drive side, and the freehub was seized into the aluminum shell so they replaced the freehub and aluminum shell. It will be shipped tomorrow with no return shippping cost
No mention of charge yet so Im assuming its being covered under some warranty

Much better than I ever expected, Kudos to Grin 👍 👍 👍 👍
 
GMAC repair update
Got the motor back today, thanks to grin for the free refurbish 👍 👍 👍 . Beyond anything I would have expected. This unused motor is haunting me to be used. Most likely I am going to build up a 29 inch wheel and see what it feels like on my Surly Ogre vs the Troll the new GMAC is currently on (29 vs 27.5 respectively). My next door neighbor who just bought my old Juiced CCX might use it as well as an upgrade.

GMAC Regen Update
Did a pretty steep ride today, the downhill is 8-10% for about a mile on a road and its easy to exceed 40mph+ before braking. At the top, the motor was at 92.5C and cooled down despite regens up to -400W (82.5C at the bottom, max speed about 35mph no braking other than regen). The -400W is limited by how much regen I want going into the battery (7amps). Bottom line, no concern about motor overheating due to regen for my setup.

I am happy with this, nice to use every now and then to save the brakes, Free with no downsides

GMAC vs BBSHD comparison from someone new to ebikes
My next door neighbor recently decided to try ebikes and bought ride1up core5 for him and his wife. He is now totally hooked on ebikes and feels like he has outgrown the core5 after 300 miles in 1.5 weeks. We went on a ride with the Troll-GMAC and BC-BBSHD and switched bikes a few times. I have never done this and its basically no comparison on how much better the torque sensing on the GMAC makes the bike feel. I actually thought the BBSHD would be better for him due to a simpler install but he was having nothing of it. It was the GMAC setup for him hands down. In the end, he bought my old Juiced CCX setup(torque sensing) with the intent of upgrading to a GMAC in the future.
 
What? We don’t need a mid drive. Tell it isn’t so… ;)
It isnt so. If I built the Ogre up with the refurbished GMAC I would just have another ebike....the last thing I need.

While the BBSHD isnt as inspiring to ride, it has its place and frankly hauls when you spank it.

Most likely my neighbor will buy the refurbished GMAC, a new CA and phaserunner when they become available and upgrade his new CCX.

You use of the 9C 212 motor has me thinking of a 72V build with that motor with the huge Grin 72V 16.5ah triangle battery. Total insanity
 
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