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Our tidy wiring kit has been a popular way to get clean cable runs and covered connectors on your ebike project. And being all black it does a reasonable stealthy job of it. But what if you’ve got a colourful bike and want a bit more zing? 

Grin’s manufacturing crew has been playing with fabric dyes and suppliers of coloured spiral wrap and zip-ties to produce bright yellow, red, and blue wiring kits too.

We love seeing ebike conversions where people pay extra attention to the look and details of their installation. So we’re starting a little contest for people who order one of the coloured wiring kits between now and Mar 1^st.  Send us a picture of your finished ebike project featuring one of these routing kits and we’ll award our favorite 2 conversions with a 20% off coupon for your next order.

The company TDCM from Taiwan has been among the more innovative players in the electric bicycle space. We’ve been carrying their bottom bracket torque sensors for a while but last year one of their motors really caught our eye. This was a direct drive motor surrounding an internal 5 speed Sturmey Archer hub.  You get the benefits of a derailleur-free 5 speed transmission with a 243% gear ratio plus a ~500-1000 watt hub motor all in one tidy package. 

We wind tunnel and dyno tested this motor last summer and liked almost everything about it, and are happy to have this in stock in a fast winding both as the bare hub and also as part of a complete kit.  The motor includes an internal 10K thermistor for temperature sensing with a V3 Cycle Analyst, and is the first hub that we are offering pre-filled with Statorade for improved thermal performance. 

Great news to kick off the New Year. We are now dropping the price of all our V2 and V3 Cycle Analyst devices, to just $95 for a V2.4 CA-DP and $125 for a V3.0 unit. Having served as our flagship product for a decade and financed most of Grin’s R&D activities, we owe a lot to the Cycle Analyst, but we feel it’s time for other products to move in as our main breadwinners and pass the CA savings back to you.

The V3.0 Cycle Analyst firmware is now officially at 3.0, no more Prelim6, p12, p13 etc.  as the latest tweaks have made it as rock stable as we could hope. Anyone with an existing CA3 can update to this firmware via the software download page. On new CA orders the USB->TTL programming cable for updating firmware is now no longer included in the package, but can easily be added as an accessory if desired.

Thank you all for the many well wishes for our 10 year anniversary celebrations, it’s been a joy having so many customers who have been around for huge chunks of the ride.

Extended Range Satiator Family

While the 10% sale is over, there are other great things to be excited about. First and foremost? We’ve started our beta sales program for high voltage Satiator chargers. Now rather than being limited to 63V or 15s packs, the 72V 5A model can work all the way up to 103V for 24s lithium batteries for those hot rod ebike applications.

There are a limited number of 24V 15A and 72V 5A units from our pilot production run available for early adopters who don’t require UL/CSA certification, and if you order by this weekend with Fedex shipping it should make it in time for the Christmas Tree.

Flexible Power Cables

Secondly, after years of wondering why there were no great heavy gauge cable sources for ebike battery and motor wiring, we decided to bite the bullet and have thousands of meters of our custom cable manufactured. 

The 3 phase motor cable has high flexibility 413 strand 12 gauge phase wire with Teflon insulation, and also includes 7 signal wires too, for your motor hall sensors and thermistors. All of this is bundled in a round 9mm diameter flexible jacket and it stays flexible all the way to -30oC.

For our custom battery cable, instead of going with 2 conductors, we went for a 4 conductor instead. A pair of heavy 13g wires and a set of thinner 18g wires also with high strand count and flexibility. That allows one cable to have say both the charging and discharging ports on a battery, or an additional tap point for powering accessories. Or, you can just parallel connect the thin and thick wires together to have 12 gauge equivalent.

2015 Housecleaning Garage Sale

And finally, we’re clearing out a bunch of used ebike stuff that has been allowed to accumulate over the past year. So if you are looking for some bargain priced garage sale items, John’s got everything posted up on an endless-sphere buy/sell thread.   

Nov 30th, 2005 marks the day that the Renaissance Bicycle Company Ltd. was formally recognized as a registered company here in BC.

Back then, we were being somewhat cutting edge offering custom layout NiMH battery packs when almost everything was lead acid. Early hub motors and mid-drive systems were battling it out. Rechargeable lithium batteries were a promise of the future but still exceedingly unreliable, motor controllers were analog and didn't even have a microchip; the DrainBrain was being hand soldered in batches of a dozen at a time in a basement; and scarcely anyone on the streets had heard of an electric bicycle. Oh the world seemed ripe with possibility.

And now here we are, 10 years on to the day. The lithium ebike packs are ubiquitous with power, energy, and reliability specs that could only be dreamed of back then. Motor controllers run sophisticated DSP's that do vector alignment of the 3 phase drive; the DrainBrain evolved several generations of Cycle Analyst and has sold over 25,000 pieces; hub motors and mid-drives are still battling it out; and you'd be hard pressed to find anyone who hasn't heard of an ebike or knows someone who rides one.

Throughout this we've managed to survive and grow year after year, leading the field in some areas while lagging in others, but always staying focused on the unique needs DIY entrepreneurs and enthusiasts who want to make their own 2-3 wheeled electric vehicle creations.

We're not much for cyber-Monday type blowout sales but as a small token we're celebrating the occasion with a blanket 10% discount on all items in our store, which will last until Dec 10th, to honor these 10 years. Simply log-in with your customer account (or create one if you haven’t done so), and you'll see the prices reduced by 10%.

Since March of this year we’ve quietly rolled out numerous minute improvements in the V3 Cycle Analyst firmware. Now the latest CA3P13 code includes support for Proportional Regenerative Braking with any Grinfineon or Phaserunner motor controller. Simply squeeze the ebrakes for a base regen and use your throttle to dial it in! Have a read of the cumulative release notes for all the details or see the video below for a quick summary.

There’s no need to upgrade if you are happy with how everything is running. But if you use the auxiliary input potentiometer, torque or PAS control, or have a system that supports proportional regen via a 0.0-0.8V throttle signal, then an update for these new features could be worthwhile.

The CA3P13 firmware package can be downloaded from here.

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.