Blog

We're looking for people who want to participate in one of the biggest recent breakthroughs in the thermal management and hence power handling capability of direct drive hub motors.  If you've got an ebike setup with motor temperature monitoring and routinely see core temperatures in the 100+ oC range, then please read on because this post is for you!

See, earlier this year we built a wind tunnel in our lab for doing full testing of hub motors in conditions that mimic riding in the road. Our motivation was to better understand and model how hot motors get in heavy use at different vehicle speeds, both for predictive reasons and see what techniques can push that working envelope further.

Well, in addition to the usual suspects of ventilation holes, vanes, and oil cooling, we also experimented with magnetically active ferrofluids. The theory was that the magnetic fluid would stay put in the air-gap and not leak out everywhere as is common with conventional oil cooling. What we didn't anticipate was just how TINY an amount was required to achieve remarkable effects.  With just 4-5 mL, you could have almost as much cooling benefit as a full cup of messy ATF, with almost no perceptible increase in the rolling drag of the wheel. 

The net effect is that you can run a given motor at about 40% higher continuous torque and power outputs without overheating.  Or correspondingly, a motor that used to run at like ~110-120 degrees in a given situation would now be sitting at a much more comfortable 70-80 degrees. Have a look here at our own GRIN designed prototype hub motor when dissipating just under 100 watts of power.  The steady state core temperature drops from 68 °C down to 43 °C. 

You get this without exposing the motor core to the outside environment like air cooling, and without the impossible sealing complications and additional rolling drag from oil fills.

What we are still looking to understand are the long term stability and maintenance concerns; whether it lasts for years and years or will need frequent or occasional replenishment, and also what if any compatibility issues might exist with magnet bonding adhesives in the motors.  If you want to be part of this endeavor, then we've got 10mL syringes of Statorade packaged and bundled and ready for you. 

Charging, Satiator 1.0 Firmware

 

One thing for sure about the electric bicycle scene is that things don't sit static, incremental improvements are happening year after year. 

Batteries

First and foremost is that the 18650 battery cell standard has evolved to specifications that were previously only dreamed of. Without changing anything to the weight or price of their packs, Allcell recently switched to a newer LG MG1 cell model. This turns the 15Ah pack into a 17Ah pack, and the 20Ah pack into 23Ah, and simultaneously cuts the internal resistance and voltage sag almost in half compared the 15 and 20Ah packs. 

 

 

 

All our Allcell packs are of this 2015 model with MG1 cells, and we've added them to the charge simulator and hub motor simulator to see the difference. 

 

Charge Simulator

It's not just LG that has been releasing cells with both high capacities (>2700mAh) and high current handling capabilities. Sony, Samsung, Panasonic etc. have all been updating their lineups of 18650 cells making this an exciting time for ebike battery capabilities. We've now refreshed the ebikes.ca charge simulator to include dozens of new and old cell models, so anyone using the Satiator charger will be able to set their full charge voltage thresholds more precisely for a specific target battery capacity.  Just select the cell type in your pack from the drop-down menu along with the correct series/parallel layout and you'll have a full charge simulation at your fingertips. 

 

 

Charging, Satiator 1.0 Firmware

And did we mention charging batteries? For those with a Satiator charging doesn't get much better. We've now released the 1.0 satiator firmware and software suite which has two major new features along with numerous small improvement tweaks to the user interface and charge behavior.

The first of these is graphing! You can now see a real time plot of your charging voltage and current every time you plug in and charge a battery pack.  The graph autoscales sensibly, and looking at the charge graph rather than just the final amp-hours can tell you interesting things, like how much time was spent in constant voltage mode versus bulk charging, and whether the current from the Satiator was reduced due to thermal rollback etc. 

 

 

 

The second major feature is charge statistics.  The V1.0 Satiator firmware not only keeps track of how many charging amp-hours and watt hours it itself has delivered over its life, it also keeps track of the total cycle statistics on each individual profile too. So now you will have an automatic record of how many cycles and kWhrs of energy you've put into your battery pack, and if you use multiple profiles on the same pack you'll have a breakdown of how often you've charged it to 80% vs 100%, fast charge vs slow charge etc.

 

This information is invaluable in understanding the life cycle costs of a battery pack under different charge scenarios, and can compliment the data from a Cycle Analyst or similar device that records the discharge statistics. The more people we have collecting real world performance data like this instead of just contrived lab test data, then the better the community as a whole can know what to expect for battery longevity. 

 

Small tweaks include a new "About Satiator" section of the setup menu that shows current info on the device, the ability to see the previous charge cycle amp-hours even after you have disconnected the pack, the ability to display battery temperature on any pack (not just NiMH/NiCad) by hooking up a thermistor, and a better fault handling behavior when dealing with packs that have problematic BMS circuits and whatnot.

 

This new 1.0 version of Satiator firmware does require a new software suite in order to display all the new information, and the software and firmware are available for download right now. Please click the appropriate link to embark on the best charging experience ever. 

 

Field Oriented Controller

And back to the subject of things getting better. The pilot run of BAC500+ field oriented motor controllers that we launched late last year was a good success, but what follows is even better. The PhaseRunner is based on ASI's BAC800 controller units with a special heatsink, potted enclosure, and cable harness all made here at Grin. It can run at higher voltages (95V instead of just 60V max), higher phase currents (80A rather than 60A), and has a smaller and narrower footprint, all at the same price. Many more details are available by reading through the endless-sphere thread starting here. 

 

We're hoping to make this a standard and stock cornerstone of our controller and kit offerings by fall of 2015, but in the meantime we're still producing a couple of these a day for advanced technical users. 

Alex DM24 Rims with 3D Drilling

Anyone who has laced a large diameter hub motor into a small diameter rim will be more than familiar with the problem of spoke angle. Just a single cross pattern will produce an angle that puts large stresses on the nipple and bends the spoke, something we've modeled on the hub motor spoke calculator for people to anticipate. Alex Rims has been offering 3D drilling of their spoke nipple holes in the rim to allow the nipple to exit at an angle rather than radially inwards, and we got a large number of these in a 20" rims size drilled out to 14 degrees which should allow you to do single cross lacing jobs when previously only radial would make sense.  

Unfortunately, the 3D drilling is not compatible with their rim eyelets at the moment, so for the 24", 26" and 700c DM24 rims we opted to go for stainless eyelets instead. 

Shop Video Tour

Last week we also had an unexpected visit from Court, who runs the excellent electric bicycle review site electricbikereview.com.  What was supposed to be just a short quick shop tour ended up taking a good chunk of the afternoon, which Court kindly recorded and uploaded to youtube. If anyone is curious to see the inner workings here at Grin and has time to spare, enjoy the video.

Sometimes we do a lot of work on a project and totally forget to announce it anywhere. That happened a few months ago when we finished a large round of enhancements to the online CA Trip Analyzer software, courtesy of the hard work of our UBC co-op students Mila and Shivan. Then moved onto our next endeavors and forgot to make a peep. 

The latest enhancements apply most specifically to the V3 Cycle Analyst devices, since the software now shows all the extended data such as human torque, motor temperature, pedal cadence etc. This extended data is shown on a second graph allowing you to customize not only which items to display, but also whether they scale on the left or right axis and how or if numeric stats on the right should be computed.

We've also made it so that named trip sections are highlighted in different colours and shown on the slider bar, allowing for easier visualization of the trip regions when communicating or sharing adventures. All of these capabilities are now summarized in the FAQ section. As always we appreciate feedback from people using these web tools. If you've got an interesting trip upload to share, please send the URL our way.  

This February we quietly added a newsletter signup to our homepage for people wanting an active update on new stuff at Grin. Many hundreds have subscribed we're glad to have gotten the first newsletter out the door this weekend. It's a long one but worth a look, future updates are expected to be shorter and sent out every few couple months to keep you abreast of our undertakings:

If you're interested in having Grin updates sent to your inbox instead of sending your browser back to our website blog all the time then consider signing up. There is no need to have an account on our store site, simply enter your email address in the box to the right. However, if you do have an accont then you can easily enable newsletter subscription from inside your account settings too.

Say Videos

As part of our effort to be a tad more proactive in sharing the good word on our products, our resident dealer rep and sales guy Danial Sgzatti has produced an excellent little intro video on the Cycle Satiator charger. This short clip is meant to help highlight the Satiator benefits without having to read tons of text on our site, and we'd welcome you to have a look.

Well, the informal Cargo Bike Championships were a real blast, with last minute entries bringing in a total to 37 participants. The event spirit wonderfully captured on video by Iaco Rocher here:

Click to see video summary of event	Members of the Grin team and their rides

We wanted to publicly congratulate the two winners of prizes sponsored by Grin. Philip Marciniak got a V3 Cycle Analyst and LED light kit for the best custom built ebike for his scratch build longjohn style bike used for his appliance repair business.

And Fabrizio Cross got a $200 gift certificate for setting the electric speed record for the fastest lap on full scratch-built semi recumbent bike, with room for both children on the back. This is one of those builds that blurs the lines a bit between ebikes and higher powered 2-wheelers, but the wide scooter wheels and full suspension do wonders to smooth travel on the bumpy roads of his hometown on Hornby Island. 

Also a shout out to Stuart and the Lecicle, who showed up with the best family bike designed by kids that we’ve ever seen!

Yuba Cycle Stokers

After a very successful pilot run, we’ve now done a full production and release of the Cycle Stoker kit for Yuba Mundo cargo bikes. Thanks to all those who’ve participated to resolve any kinks as we expanded this kit to the popular Yuba platform. We’ve updated the Cycle Stoker info page has recently to include a lot more details about this mid-drive option to answer questions for anyone else who is considering it

For those still awaiting a Cycle Stoker kit for Big Dummy cargo bikes, that will be next inline on this project. 

This has been an awesome time for alternative transportation in Vancouver. Not only did we learn that non-car trips (biking, walking, transit) outnumbered private vehicle trips for the first time ever; cycling use in the city jumped another 20% last year, the hopelessly archaic Business Improvement Association has finally acknowledged that bike lanes are good for business, and the weather and turn-out for Bike to Work Week has been amazing.  We’d love to know exactly how much of a role electric assist is playing in that, but it’s no doubt a very large factor for some. 

Let’s not forget to celebrate all this at the wrap-up BBQ on Friday at Creekside Park besides Science World. The full details of the Cargo Bike Championship have been posted to the participants. It includes a race where you pick up more cargo on each lap and a host of prize categories, and should be good fun with nearly two dozen cargo bikes of all types in the mix.

For the categories of “Best Custom Built Cargo Bike”, and “Fastest Time with Electric Assist” we’ll be awarding winners with their choice of:

• A) A Cycle Satiator universal battery charger.
• B) A Cycle Analyst and front/rear ebike lighting system
• C) A $300 Grin Credit towards the purchase of an eZee conversion kit, or
• D) A $200 gift certificate for anything at Grin

For all the other categories we’ll be giving away gourmet popsicles from our friend Johnny, who’s been making and selling unbelievably tasty cold treats from his mobile trike:
https://johnnys-pops.com/

Because of this event, we will be closing our shop early on Friday at 4pm so that all our staff can participate. To our local customers and friends, we hope to see you there too!

The classic V2 Cycle Analyst series hasn’t seen a firmware update in several years, and it’s time we fix that.  For anyone with a V2.3 Cycle Analyst, we’ve now got two more firmware options that you might like, both featuring the battery state-of-charge (SOC) icon previously only available with the V3 devices.

The first is a special Marine Firmware that we developed for a Dutch dealer. This trimmed down code is ideal for anyone using the V2 CA as a power monitoring device in applications where there is no need for speed and distance tracking, just watts, amp-hours, volts etc.  The Auxiliary Potentiometer Input has been re-purposed as a temperature input for thermal monitoring if desired too.

Main Screen showing Amp Hours and Battery SOC Icon	Amp-hours toggles to temperature readout if enabled	Display of recharge percentage and recharging Ah

The second firmware update is a general purpose V2.4 release for vehicle usage. To a first order, this is very much like the V2.3 CA code with the addition of a battery icon, but there are many changes in the back-end and setup menus too which should be appreciated, including better rejection of spurious speed readings if the spoke magnet and pickup sensor become misaligned.

You can update any of the V2.3 Cycle Analyst devices (But not V2.25 and earlier) using the same software tool and programming cable as a V3 CA, as explained here. This update will reset your total life cycle statistics, so before reflashing be sure to write down your total Amp-hours, Distance, Battery Cycles, and other custom settings so that you can re-enter those values later.

So if you have an inkling to try out the latest, please load the code above and send us your feedback.

There are few things we love more than riding around Vancouver hauling stuff on electric cargo bikes; turning heads and getting high fives and thumbs up while shuttling goods back to our shop at Grin. So we were smitten to see that Vancouver will be hosting it’s first every Cargo Bike Championship on May 29th, right at the end of Bike to Work Week, courtesy of Modacity and HUB. Read about it right here.

What’s a Cargo Bike Championship exactly? We don’t really know, but we figure it’s going to involve some kind of informal cargo hauling contest, some kind of vehicle rally, some kind of judging, and of course prizes! On that front we’re going to be sponsoring some very big awards, like Satiators and Lumenators and perhaps even a full conversion kit. We’ll update on the details as they materialize.

In the meantime though, if you ride a cargo bike of any kind here in Vancouver, whether for transporting kids or your full suite of work tools, then come help us to showcase this other side of utility cycling. Modacity is looking for participants to register their bikes by May 18th, so get your details in and lets make this a great little rally. It's timed to coincide with the wrap-up BBQ at creekside park from 4-7pm, where there will be tons of cyclists gathered and free foodstuff too. 

Last year around this time we got our Torque Arms listed and stocked at Amazon for faster and cheaper shipping to US customers. Well we can now add to the mix the Grin Lumenators Lights, USB Power Adapter, and Cycle Satiator Charger too. So if you're after just one of these items and are in the United States, then you should find Amazon can deliver it to you quicker than we can here in Canada.