Blog

The torque sensor options at Grin have been getting better and better. We now have a cup adapter for the popular Sempu sensors which extends the flanges out so that they fit bike frames with 73mm bottom bracket shells. For the longest time people with 73mm BB's have been out of luck for aftermarket torque sensors, but no more.

In addition, we have a new lineup of torque sensors from NCTE to replace the long out-of-stock THUN devices. This restores the option for a true transducer that measures the actual spindle torsion. They provide an accurate human watts readout, and unlike other sensors they can be used in mid-drive setups where the motor is driving the right side chain.

To help this DIY mid-drive use case we've brought in stock the extra long 136mm spindle option, providing additional clearance for motors and extra chainrings on the right side.

To learn more about these different sensor types and how to choose the best one for your ebike, have a read of our newly completed Advanced PAS Kit article. It should help demystify things.

And finally, Robbie made a nice video this summer showing the installation process for the Sempu sensors. We hope this provides a clear idea of what is involved in adding one of these torque sensors to your ebike build.

This title says it all. This has been an epic summer and an epic year by any measure. After completing their planned leg of the 2018 Suntrip last month, Justin and Anne-Sophie got married in August with a boat and water themed ceremony, and had the tandem trike safely returned to Vancouver last week.

We've created a single page with all the videos, media links, and a new image gallery from the trip so that you can see access all the info from one place. :

Meanwhile our video editor Aaron has been compiling our varied footage from the trip into short clips. The first day video showing most of the other riders was published a few weeks ago:

And we just completed the 2nd in the series showing highlights from Switzerland through to Serbia:

In the meantime, this has been our busiest summer in the store ever in terms of sales and new product developments. We want to thank Phil and Christoph who both joined the Grin team for the summer months keeping the shop under control and wish them the best in their continued studies.

For our 2nd ever customer profile we're going to feature Mark Havran.

While we're still fairly new to the solar ebike game, Mark is among the (suprisingly numerous) Grin customers who've been thinking about and experimenting with solar bikes for many years. After he shared pictures of his latest project and mentioned his round the world touring ambitions, we thought we had to do a small feature on this guy. A quick last minute trip to Maker Faire was arranged to meet up, and here we present, Mark Havran:

For additional technical details and insights on his build and plans, have a read of his recently started endless-sphere thread. 

You can also follow Mark's adventures via Instagram at @SolarEbike.

After quite a long testing and verification period we're finally ready to release our 3.11 firmware update for the CA3! It is highly recommended to update your CA3 to this software, especially if you're on 3.1, for some important bug fixes and much improved PAS response.

You can grab the latest firmware using the CA software utility by clicking the  "Get New Firmware" button - happy flashing!

We are also happy to let everyone know that the Crystalyte motor shipment has finally arrived after some delays at the port!. As you can see, we're very excited to have these back in stock to help you all out with your projects.

Included in this shipment are the much awaited 3540 motors with their slick "UFO" design. These are the replacements for the older square style "H" motors, you may have noticed that this change was implemented last year with the 3525 front and rear motors. As always, we have the motors customized with a 10K NTC thermistor for thermal rollback using the CA3.

We also have restocked the classic Stokemonkey direct-drive motor, and Brompton NSM and SAW20 motors.

We're about 65km out of Zagreb in Croatia now, cloudy weather, stopped for a brief rest on the side of the road... JLE

You can follow Justin's most recent updates on the Endless-Sphere forums - here's his latest post. If you're curious how this whole tandem-solar-pedal-rowing-trike came about, you can start reading at the beginning, here!

Justin and Anne-Sophie have been on the road in Europe for about a week now, catching as much sun as they can on the Suntrip. Since the start of the trip in Lyon and the official start of the race in Chamonix, they have been trending on a more southerly route towards Turkey and Iran. As they get used to the style of travel and the nuances of riding a three-wheeled solar vehicle all day they have had their ups...

and downs...

That said, I think their level of stoke so far can be summarized by Justin in this picture...

Exhaustion with a Grin.

Find some lovely photo updates via Instagram when Justin and An'so have WiFi: Grin Tech SunTrip Instagram

The official Suntrip website can be accessed here: https://www.thesuntrip.com/

Happy riding and sunny weather to you both!

After quite a long testing and verification period we're finally ready to release our 3.11 firmware update for the CA3! It is highly recommended to update your CA3 to this software, especially if you're on 3.1, for some important bug fixes and much improved PAS response.

You can grab the latest firmware using the CA software utility by clicking the  "Get New Firmware" button - happy flashing!

We are also happy to let everyone know that the Crystalyte motor shipment has finally arrived after some delays at the port!. As you can see, we're very excited to have these back in stock to help you all out with your projects.

Included in this shipment are the much awaited 3540 motors with their slick "UFO" design. These are the replacements for the older square style "H" motors, you may have noticed that this change was implemented last year with the 3525 front and rear motors. As always, we have the motors customized with a 10K NTC thermistor for thermal rollback using the CA3 and an easy Statorade fill port under the disk brake mounts.

We also have restocked the classic Stokemonkey direct-drive motor, and Brompton NSM and SAW20 motors.

The clock is fast approaching with just 3 weeks left before Justin and Anne-Sophie head to France for the Suntrip solar ebike race. We've recently made great progress in adapting a craigslist trike purchase into the back-to-back-tandem-solar-electric-rowbike of our dreams. What started off as this:

Is now looking more like this!

Actually, that's from last weekend. The current iteration has a solar roof installed with electric power and turned plenty of heads on it's maiden solar powered trip to the town of Gibsons and back.

If you want to see all the latest build updates, design challenges, and test rides, then now would be a great time to check out our Youtube channel. We've been doing regular VLog posts in preparation for this trip and will be releasing several videos a week during the upcoming crunch.

And while we are talking about videos and rowing bikes, we wanted to share the conversion project from this winter that partly solidified our decision to do the Suntrip tour with a rowing bike component in the first place.

If you've got a rowing bike of any kind that you've been looking to electrify, we'd love to hear from you too to see if the new rowbike mode PAS feature in the CA3.1 would fit the application. 

One of our favorite aspects of this business is the numerous amazing and creative people that we get to interact with on a daily basis. Ebike technology has a way of attracting people from all walks of life who see an opportunity to solve problems around mobility and transport, often in ways we would have never imagined.

We have a goal this year to release a monthly video profile on someone with a story to tell. That includes those whose lives has been dramatically affected in some way by ebikes, fellow entrepreneurs pursuing ideas that can positively impact the lives of others, and also those who just relish in their own DIY ebike builds.

We are kicking off this series with a quick look at Keith Forbes. Keith showed up unannounced at our shop a year and a half ago, asking if there may be any work opportunities as he was considering a move to Vancouver from Trinidad and had something of a personal interest in transportation technology. We'll let the video show what he's been up to since then!

If you want to stay tuned in to updates like this, now would probably be a good time to subscribe to our youtube channel  We have dozens of videos in our editing pipeline that you won't want to miss. 

In the last month we introduced two new geared motor options in our lineup.

The first of these is the Bafang G60 fatbike motor. It's got a 175mm axle that can fit fatbikes with up to 190mm dropouts using spacers, it uses a cassette freehub for broadest gear compatibility, and it has an impressive power and torque output that approaches the eZee hub motors.

We've got this hub fully modeled on our simulator and available to purchase as either a bare hub or part of a full kit. Combined with the 140mm Sempu torque sensor it's now possible to do proportional torque assist electric fatbike conversion.

The other motor is the G311, a front equivalent to the wonderfully silent G310 rear motors we introduced late last year. This motor will be replacing the G01 hub for our front mini geared kits. It's a tad lighter (2.3kg), much quieter (spiral gears!), but still has the features from the G01 that we loved. That means a side cable exit, ISO disk rotor compatibility, and 10mm round axle.

We have a limited quantity of these new hubs stocked in 3 different winding speeds, from 8.4 to 12 rpm/V for various wheel sizes, and have a large sea shipment due to arrive in early June.

Our remaining fast and standard wind G01 motors are now on sale too.

The last 8 months we've been wrapping up some long duration testing of Statorade across different hub motor lines and performing experiments confirming its long term stability. These results have us pumped to introduce this motor cooling solution beyond DIY'ers and into wider markets. As an example, have a look at the video we below showing the effect this has on a small direct drive folding bike motor.

This was filmed last summer when we had a customer requesting a 72V SAW20 Brompton electric conversion. Normally that would be a recipe for motor overheating problems, but as you can see, Statorade is the magic bullet that makes it work.

We've updated our Statorade page to include all the latest test info, and also publicly posted on the forums results on the longevity testing, performance with skateboard hubs, characterization of fill quantity vs RPM, and even wrote a detailed study on the potential benefits of Statorade use in BionX motors.

For people wanting to push the effects of Statorade to the max, the Australian made Hubsinks can clamp on to your motor shell and provide additional cooling fins to shed heat to ambient air. These fit our new MXUS Cassette motors, and the 9C, Crystalyte H, and many others. These are listed on our new store category for motor cooling mods. And like other small products, we try to  keep a stock of 10mL Statorade syringes on Amazon for easy shipping to US customers. They are sold out now but another shipment is inbound.