In the e-bike world, there are such things as ‘plus‘ and ‘fat‘ tire bikes. Many of the factory-built e-bikes now use the plus-size tire format for better contact with the road/trail surface (larger ‘contact patch’ for you motorcycle riders out there). And now you’re starting to see even wider tires on some factory e-bikes, presumably to improve your ride over loose gravel, sand, etc. For the most part though, fat tire bikes just look cool, and that’s probably enough justification to own one. So now I do…

I recently bought Costco’s Northrock XC00 Fat Tire Bike for $400 on sale (plus tax). Here it is:

The XC00 has no front or rear shocks, so no additional suspension components, but with the large tires I really don’t think it needs them. The tires seem to absorb bumps in the road much better than narrower tires would. Also, note that this bike comes with disc brakes (albeit mechanical) so I’m thinking that there’s very little that needs changing to turn this into a full-fledged e-bike. So that’s what I’m going to do.

Originally, I had decided to go with the Bafang BBSHD 1000w mid-drive motor for this build. I ordered the motor from China, but it didn’t arrive after 1 month so my money was refunded by PayPal (thank you PayPal!). Then I have decided to go with the Bafang 48v 1000w rear-hub motor (the G062,1000.DC motor) designed for a 26″ fat tire bike with a 175-180mm dropout and rear disc brake. This seemed like the perfect motor for my XC00. The only gotcha is that this too will be coming from China and shipping is expected to take 2 months (here by Sept. 27). The order was through Amazon, so I have their purchase protection. Plus the final price was a LOT less than the mid-drive conversion ($560 incl. tax and shipping versus $790). Before adding the cost of the battery (which I already have), this will be a $1000 build. I think this is going to be a pretty spectacular build for $1300 when all is said and done.

Here’s the specific motor and display I ordered from Accolmile via Amazon:

BAFANG 48V 1000W Rear Hub Motor : 26 Inch Fat Tire Electric Bike Conversion Kit with Battery (Optional) for Rear Cassette Wheel with LCD Display & PAS ($479 before tax and shipping)

Well, that didn’t go exactly as planned. It’s possible that the order I placed on Amazon for the Bafang motor was a ‘bait and switch’ deal. The vendor said the Bafang was out of stock and I could wait until sometime in September “when it might be in stock again”, OR accept a substitute motor they claim is the same as the Bafang 1000w motor and they would refund shipping charges. I opted for the latter just because I want to see how the replacement unit performs – consider this an experiment.

The label on the replacement unit is ‘Sutto’. The first thing I noticed was how rough the spoke nipples were. I had to dress them so they wouldn’t puncture the tube. Next, the wheel has a 10-12mm offset when installed on the XC00 bike, so that was taken care of by Bike Works in Newtown. Otherwise, everything fit up nicely and performed well on my 10 mile test ride this afternoon.

Summary of issues and pleasant surprises:

Concern #1: The spoke nipples (the ends on the tube side of the rim) are VERY rough and would cause a flat if not filed and protected with a rim strip, so that’s job #1. Done…

Concern #2: The wheel mounted on the Sutto hub motor requires adjustment of 10 to 12 mm toward the brake side, called dishing. The charge to do this adjustment was $25 plus tax at Bike Works, Newtown, which I think is very reasonable and they did a great job!

Pleasant surprise #1: This hub motor comes with a quick disconnect fitting about 8 inches from the hub that will make rear wheel removal and repair MUCH simpler than my Voilamart rear hub motors! This is a big deal and it appears Bafang/Sutto figured this out.

Pleasant surprise #2: The motor says Sutto, but all the other parts (esp. the controller and display) are labeled ‘Bafang’. This is a good sign.

Pictures:

As mentioned above, the e-bike doesn’t have PAS or motor cutout switches on the brake levers. Considering the way I ride my rear-hub e-bikes, this throttle-only configuration is perfect. I pedal most of the time, then augment forward motion with throttle as needed. With this setup, the PAS settings determine how much power is applied with the throttle. I’ll usually run this bike between 3 and 4, on a 9 point scale.

If I were to do this build again, I would try to find a reliable source for the Bafang G062 motor, and now I know I would have to dish the wheel for this particular Costco bike, which is not a big deal. Otherwise, this was the easiest and most cost-effective e-bike build to date, and it’s an absolute joy to ride.

PS – I plan to build another one of these with the original Bafang motor when the XC00 goes on sale again ($400 is a great price for this bike!). Also, I created an image of the rear wheel offset that’s required when mating the Bafang 1000w geared hub kit to this frame:

In my e-bike class I discuss the ubiquitous 18650 lithium-ion cell used in most e-bike batteries today. These batteries have been around for a while and are used in many laptop computers, cordless power tools, some electric cars, electric kick scooters, most e-bikes, portable powerbanks, electronic cigarettes, and some LED flashlights. This broad acceptance usually translates into lower cost and improved quality/reliability.

So, the question is, if the 18650 cell is working so well, why change? And what’s next for e-bikes? Good question! I’m glad you asked…

Having done some research, there are a few factors to consider when selecting certain types of batteries for your e-bike. One factor is ‘space’. It’s likely that you be using a 18650 cell pack if you’re cramped on space. The cells are slightly smaller than the next cell configuration, the 21700 cells that are also fairly common these days, but are a bit more expensive than the 18650s, and tend to be used in applications that require more energy and can tolerate greater weight and space than a battery pack using the 18650 cells.

Here’s a short thread that discusses the differences between the 18650 and 21700 cells:

18650 cells VS. 21700 cells
byu/ebikenoob inebikes

From this link, I quote:

“21700 cells use the same tech as 18650 cells meaning it delivers the same power per weight, but just by size comparison the 21700 cell is 46% more bigger.

Both have same voltage, but 21700 cells can deliver 40% more power via capacity and amperage.

If you want power, slim build, and less capacity for cheap, get 18650

If you want the same power, bulkier build, and travel 40% farther, worry less about overheating at a premium, get 21700s”

And summarized from a recent e-mail exchange with Matt Robertson (Tales On Two Wheels):

Matt has been using both battery configurations in his builds. His Bullitt (ebike) uses a custom 32ah Samsung 35E cell pack, which are 21700 cells.  And the Luna V2 (used for his Apostate build) is using 18650’s.  The pack on the Apostate was chosen primarily because it was a perfect fit for the frame.  Everything else was secondary… you can get more details about his rationale for using the Luna V2 battery for this build in his recent Day 3 article.

Matt continues:

“At this point in time, 21700 cells are superior but not hugely so.  Its not enough of an improvement to be the sole decision maker.  As you can see above, that one pack had a number of things going for it and cell content was secondary. Those cells have been available for some time but have not taken over the world.  Primarily due to cost. 

It really depends on what you are looking to do with the battery, how big it is.  How expensive the cells are when making your buy decision.” 

Which brings us to a relatively recent development in battery tech that could find its way into the e-bike market, and that’s LiFePo4.  LiFeP04 (lithium iron phosphate) tends to be less energy dense and heavier, but a pack can be charged up to 100% and left there for extended periods, and those packs are good for 2000-3000 cycles whereas a li-nmc/18650/21700 pack is going to live about 400 cycles (worse case).  Also there is no explosion or fire risk. BTR Power is selling them on Amazon for e-bike batteries although they really are better suited for ‘cargo’ bike apps where you can live with a bigger battery.

Well that’s all I know about e-bike batteries for the moment, and my head hurts from thinking about this topic. Many thanks to Matt Robertson for steering me in the right direction to help y’all learn a bit about battery tech. And for the moment, I have a lot invested in 18650 battery packs, so I guess I’m just going to use those up before I switch to any of the newer battery tech. And maybe by then there will be something better and cheaper on the market anyway. With all the innovation happening in the EV automotive space, there’s likely to be trickle-down into the e-bike segment, especially for the ‘performance’ e-bike market. I was viewing a YouTube video recently (Future E Bike Technology Part 3) where a comment was made that most ‘serious’ mountain bikes in the future will have some ‘e’ components. To get there though, battery weight needs to decrease, range needs to increase, and e-mountain bike (eMTB) systems need to improve.

Exciting stuff for sure!

Skarper’s revolutionary ebike conversion kit uses a disc-brake rotor to drive your bike

Prototype kit claimed to turn any disc-brake bike into an electric bike

By Warren Rossiter

Published: June 15, 2022 at 9:00 am

British start-up Skarper has unveiled a new e-bike conversion kit that uses a specially designed disc brake rotor to provide power to your bike.

Most electric bike conversion kits are not easily removable because of the effort involved in switching out a wheel, cables, batteries and fittings.

However, the new Skarper system eliminates that issue by containing everything within a compact single unit that has a unique and patent-protected design to drive your bike’s rear wheel.

We’ve spent an afternoon using the system for an exclusive first-ride review and, so far, we’re impressed.

What you need to know about Skarper

• The Skarper unit requires you to replace the rear disc rotor with its rotor/drive unit
• It weighs in at a claimed 3kg
• Skarper’s rotor works as both brake and drive, and adds just 300g to your bike
• Once the disc is installed, fitting/removing takes seconds
• Claimed range of up to 60km
• Charge time of 2.5 hours

What is it?

Skarper’s patented DiskDrive rotor replaces the stock rotor on your bike. Skarper

Skarper’s electric bike conversion kit is housed inside a one-piece drive and battery unit. The unit clips onto specially designed tabs that you fit to your non-driveside chainstay.

The motor then drives a purpose-built rotor, which the brand has dubbed the DiskDrive. Most electric bike conversion kits use a front-hub motor, a bolt-on mid-drive unit or rear-wheel motor to provide propulsion.

Like most ebike conversion kits, on Skarper’s system, a cadence sensor attaches to the cranks to control power output.

A simple fitting on the chainstay stabilises the Skarper. Skarper

Who is behind the Skarper ebike conversion kit?

Sensors and the control system’s algorithm combine to deliver power when you need it. Skarper

Skarper says it has a team of more than a dozen engineers and designers working out of its London base. Leading development is inventor Dr Alastair Darwood.

Dr Darwood already has plenty of innovations under his belt associated with his medical training. These include orthopaedic and anaesthetic medical devices developed while working in the NHS.

Supporting Darwood’s innovative electric bike conversion kit is a group of cyclists who’ve all backed the company privately.

Sir Chris Hoy helped with the R&D of the Skarper and invested in the project. Skarper

The Skarper’s investors include six-time Olympic and 11-time world champion Sir Chris Hoy, who has also been heavily involved in the testing and development of the unit.

He explains: “I’ve always been an advocate of getting more people on bikes, regardless of their fitness, ability or age, and I’ve discovered that ebikes can play a huge role in making cycling more accessible to anyone.

“It opens up opportunities – whether it’s making a commute possible which would otherwise have been too difficult, keeping pace with a fitter friend for a challenging bike ride, returning to riding after an injury or illness, or just going further on your rides and seeing more for the same effort.”

The self-contained motor, battery and ‘brain’ of the system is remarkably compact and weighs in at just 3kg. Skarper

What’s next?

Simple fitting and its compact dimensions could make the Skarper a true game changer. Skarper

Skarper is remaining tight-lipped on the full details, but alongside the road/urban unit seen here, the brand has also been working with Red Bull Advanced Technologies on an off-road version.

Skarper claims this unit has “huge amounts of power and plenty of torque. It means you can clip-on the system to carry you to the top of the mountain, unhook it and stow it in your pack and then you’re free to ride the trails on your / without the added weight and expense of an e-mountain bike“.

When will it be available?

Skarper promises to make turning any bike into an ebike a straightforward process. Skarper

Skarper has now committed to full production, with delivery intended for 2023.

No fixed price has been set as yet, but Skarper tells us that the target price is £1,000.

Skarper also claims it’s in discussions with major bike brands about the opportunity to fit the DiskDrive disc brake rotor as standard.

Skarper electric bike conversion kit first-ride impressions

Warren Rossiter, senior technical editor

At just 3kg, the Skarper unit makes your bike much lighter than most electric bikes. Skarper

While at Skarper’s office, I fitted a prototype system to a modest Merida hybrid. This involved a switch of the centre-lock disc rotor for Skarper’s DiskDrive, attaching the Bluetooth cadence sensor to the cranks and then hooking the unit onto the rear chainstay, with its driveshaft plugging into the keyed slot on the rotor.

Taking the unit out of the box and getting it powered up and ready to ride took a matter of minutes.

I headed out onto the streets of Camden, in London, to try out the system.

The system provides assistance quickly from a standing start, progressively increasing the power smoothly and making for quick getaways from traffic lights.

We headed to Highgate hill, which rises around 60m in elevation. I came away impressed by how easily the Skarper coped with this short urban climb.

Unlike most electric bikes, the Skarper uses a combination of sensors and control algorithms to respond to the terrain and your input. Power delivery was smooth and predictable.

It’s akin to the level of assistance you get from lighter ebike systems, such as Mahle’s ebikemotion or Fazua’s mid-drive system. However, this self-contained unit, without a separate high-capacity battery, won’t have the same range as either of those systems.

The Skarper isn’t just for commuter bikes – you can fit it to your road bike, gravel bike, mountain bike or anything with a disc brake. Skarper

While the Skarper is pretty much self-contained and self-controlled, the brand is also working on a smartphone app to allow the owner to tune the system and perform firmware updates and upgrades.

I asked about long-term concerns on driving the rear wheel via the brake rotor. Darwood explains that the force a rotor experiences under braking far exceeds any amount of power the Skarper system delivers. This, he says, means the system is said to operate well within existing standards.

With removal in seconds, compact dimensions and a 2.5-hour recharge time, the Skarper can truly be charged at your desk. Skarper

Having spent 45 minutes riding the Skarper, and in prototype guise with a fabricated casing around the patented internals, I’m not ready to commit to a full-test opinion yet.

I was, however, impressed by just how good the system feels.

The unit even integrates a rear light into its locking lever. Skarper

There’s enough power for urban hills and the power curve is smooth, progressive and instant in both turning on and off. The system also feels essentially drag-free when it’s not running (above the 25kph EU limit).

Skarper’s COO, Uri Meirovich, was quick to point out after my short test ride that the aim of the system is not to take on existing conversion kits, but to offer a viable alternative to expensive mid-drive and hub motor systems without the need to purchase a full-on electric bike.

The goal of producing a credible alternative to existing ebikes, while you can still use your own bike is potentially game-changing, but we’ll have to reserve judgement until we can get the Skarper on long-term test.

Author

Warren Rossiter

Senior technical editor

Warren Rossiter is BikeRadar and Cycling Plus magazine’s senior technical editor for road and gravel. Having been testing bikes for more than 20 years, Warren has an encyclopedic knowledge of road cycling and has been the mastermind behind our Road Bike of the Year test for more than a decade. He’s also a regular presenter on the BikeRadar Podcast and on BikeRadar’s YouTube channel. In his time as a cycling journalist, Warren has written for Mountain Biking UK, What Mountain Bike, Urban Cyclist, Procycling, Cyclingnews, Total Bike, Total Mountain Bike and T3. Over the years, Warren has written about thousands of bikes and tested more than 2,500 – from budget road bikes to five-figure superbikes. He has covered all the major innovations in cycling this century, and reported from launches, trade shows and industry events in Europe, Asia, Australia, North American and Africa. While Warren loves fast road bikes and the latest gravel bikes, he also believes electric bikes are the future of transport. You’ll regularly find him commuting on an ebike and he longs for the day when everyone else follows suit. You will find snaps of Warren’s daily rides on the Instagram account of our sister publication, Cycling Plus (@cyclingplus).

A friend from my distant past contacted me a few days ago to let me know he had electrified a Schwinn trike. He used the Swytch kit which powers the front hub, but every time I have researched this kit it’s out of stock. So, after I show you what he did, I’ll show you the kit I would use, which is just a little less money than Swytch. So here’s what Glen (coincidence?) did:

The Swytch install took him about 1.5-2 hours. In his own words…

The kit comes with a new front wheel, with motor pre-installed. Get a tire on the new rim and it’s ready to install. Then you mount the battery to your handle bars, and run a connecting wire down to the motor. Then, run a second wire to a stationary sensor that you mount on the frame adjacent to the pedals. Then, you mount a ring with small round imbedded magnets to the pedals. Once you turn the battery on and set your desired power, you get on and start pedaling.  The engine immediately responds. Stop pedaling and you stop the power…pedal faster and motor increases speed. The power setting controls the amount of assist that is generated in response to pedal speed. I’ve found the mid setting gives me adequate power and speed and excellent range.

The big benefit for me, I just turned 77, is that you are forced to pedal to activate the power assist, no pedal, no motor, pure and simple. Also, with the battery turned off, I sense very little difference in pedal power required from the standard wheel being installed. I’ve included pictures below, that I think will give you an idea of the simplicity of the setup.

The lights on the left show battery charge and the light on the right is the power setting.

The wires I’m not using are customizing the setup. They do have a optional throttle kit, where you don’t have to pedal, but that would defeat the exercise factor I was looking for.

So, a single connecting cable to the motor.

And, a single cable to the sensor. You can see the ring that mounts on the pedal and the sensor reacts to the rotation of the magnets.

OK, so that’s how Glen did it. Seems pretty straightforward. But instead, I would go with this Bafang kit and Joyisi battery:

BAFANG 8fun 48V 500W Front Wheel Hub Assembly Motor Kit 26 Inch Front Wheel Electric Bike Kit with P850C Display ($310)

plus a 

Joyisi 48V Ebike Battery 13Ah Lithium Battery for 500W Bike Motor Conversion Kit ($265)

Glen says the price he paid is similar to the prices shown above. There will be a bit more installation work to be done with the Bafang kit since you’ll need to find a place to put the controller and battery, and then connect everything up. Swytch appears to simplify this aspect of the conversion.

Just kidding! I think I can continue to provide a valuable service to e-bike DIYers and those interested in buying factory e-bikes in our area. However, I recently discovered a resource that is about one light year (roughly 5.879e+12 miles for those interested in this sort of stuff) ahead of me in this space. Let me introduce Matt Robertson (no, not this one), but this one. Matt’s blog is ‘Tales On Two Wheels‘ where he writes about things like “How To Build An Ebike From Scratch“. The difference between Matt’s approach and mine is that Matt is MUCH more organized and informative than I have been. Therefore, if you’re thinking about building your own e-bike (from scratch), DEFINITELY consult Matt’s site BEFORE starting your project.

I’m just thinking of all the mistakes I could have avoided had I discovered this resource before I started…

Other helpful advice you’ll get from Matt’s site includes (but is in no way limited to):

• How To Ride a Mid Drive Ebike Without Breaking it
• Li-Ion Ebike Battery Charge Charts
• Range Anxiety? Be Prepared (and Stop Worrying)
• (e)Bike Flat Prevention
• Etc, Etc…

Matt’s ‘Building an E-Bike from Scratch‘ is a work in progress which I plan to follow through to the end. Completed to date (May 2022) are Planning, Hunting, Tinkering, and Buying. Next up is Assembling (can’t wait!), followed by Perfecting. As has been the case with each of my builds, ‘Perfecting’ is a continuous process. Your completed build will mostly work, but then there’s a slight chain alignment issue, or brake adjustment, or you finally decide to ditch your front derailleur because you never use it and you want to go to a larger single narrow-wide chainring anyway, etc.

This matter of ‘Perfecting’ is one of the real benefits of building your own e-bike. You own it, you built it, and you can change it any way you want to without paying a premium for ‘factory’ parts or voiding your warranty. It gives you complete freedom to dial your e-bike in to address your specific needs and abilities.

So again, kudos to Matt for providing this excellent resource to e-bike DIYers – thanks! You’re providing a great resource for those just starting out…

Having recently upgraded the display on my Bafang mid-drive e-bike, I’m now an advocate of displays that provide actual battery voltage, rather than just a relative indication of charge via bars. Here’s what I’m talking about. Here’s the display I’m using on my two rear hub e-bikes. It’s the SW900 LCD display:

It’s not a bad display. It just doesn’t give me all the information I would like to have about my battery.

Better is this display I recently purchased for the mid-drive e-bike. It’s the Bafang 850C/DPC14 LCD color display.

You’ll notice next to the battery indicator, there’s a an indication of the actual voltage remaining in the battery. Why is this important you might ask?

Glad you asked! In previous posts I made the point that you can potentially improve the longevity of your battery by not letting the charge level get below 20%, and when recharging, charge to 80% most of the time. I only do full (100%) charges about every 5th charge to re-balance my battery’s cells.

Now, since I said 20% for the lowest discharge, and 80% for the highest charge, how many volts does that relate to when charging a 48 volt battery? Good question! After much digging, I this excellent resource which answers the question: https://talesontwowheels.com/2019/10/02/li-ion-ebike-battery-charge-charts/ (thanks to Matt Robertson for doing the heavy lifting to make this information available to us all!)

From this ’48 volt’ chart, I conclude that I should not let my 48 volt battery discharge below about 42 volts, nor charge more than about 51.5 volts with an 80% charge. To manage this charge level, I have been using the Luna Charger 48V Advanced 300W Ebike Charger (currently out of stock), though this charger works just as well, is in stock, and costs less – 48v 3amp Luna Mini Charger.

And just to add a little more weight to my claim that charging your battery to 80% rather than 100% as a routine thing, here’s yet another chart (source):

That’s all for now. Thanks for listening!

For e-bikes, that is. After converting my first Trek to a rear hub e-bike, I have not once used my front derailleur. The chain remains on the highest chainring, and any gear changes happen on the rear 7-speed cluster. All my riding is on roads, not single-track trails, though our part of Pennsylvania is fairly hilly, so some shifting is required – not really single-speed territory.

I’m also finding that I can run a larger single chainring than I would normally use on a non-electric bike. My second build, also a Trek, is running a 48-tooth narrow-wide chainring, and my first build will soon be running a 50-tooth chainring. I’ll provide a few pictures below when the swap is complete.

Bottom line: There really doesn’t seem to be any need to use a front derailleur on any e-bike, rear hub or mid-drive. It’s just adds unnecessary cost and complexity.

Parts:
BUCKLOS 104 BCD Mountain Bike Single Speed Crankset, 170mm MTB Square Taper Crankset ($30)

YBEKI 50T Chainring 104BCD Round Oval Narrow Wide Single Bike Chainring ($24)

And the evidence:

And a ‘before‘ picture so we know where we came from:

PS – I rode 12 miles this afternoon and really like the change. With this new gear ratio (50×12 in the highest gear) I can still pedal at 35mph. 20mph cruise in the middle gears is perfect. Build #2 is running a 48-tooth chainring which is probably more appropriate for group and trail rides. Having a few bikes, each with its own unique characteristics, I find myself selecting the bike that best fits a planned ride.

As important as tires and wheels are for e-bike safety, brakes might be even more critical. Not being able to stop effectively will eventually be an issue. Better to deal with your brake issues sooner than later. Brakes are all about ‘stopping power’. In fact, if you’re riding your e-bike correctly, you’ll use your front brake about 90% of the time where 70 to 80% of your effective braking occurs. This is not to say that rear brakes aren’t important, they are. But your best stopping power is coming from the front brake.

In the old days, ‘caliper brakes’ were the thing. Mountain bikes tended to have brakes that provided more leverage, hence greater braking force, while road bikes had smaller calipers which exerted less force, but were sufficient for the job at hand. Today, only inexpensive bicycles have caliper brakes, and no ‘factory’ e-bike I have seen recently has calipers. Yet, if you’re contemplating converting an old bicycle to an e-bike, you might well decide to keep the caliper brakes rather than upgrading to disc brakes. That’s fine as long as the brakes your keeping have ample stopping power.

For example, my mid-drive e-bike has caliper brakes that are very effective. I see no need to upgrade. I replaced the brake pads with pads that have good stopping power and will stay with that. As mentioned a moment ago, most of the stopping power is being done on the front wheel. With that in mind, my first DIY e-bike has a ‘hydraulic’ disc on the front (major stopping power) and a caliper on the back. This configuration is working really well for that bike.

Then when it came time to build my second DIY e-bike, I decided to try out ‘mechanical’ disc brakes fore and aft and I’m very happy with the results. I was also surprised with this build how inexpensive a good set of mechanical disc brakes could be. This is the set I chose and I’m delighted with their performance: RUJOI Mechanical Disc Brake Kit, Aluminum Front and Rear Caliper, 160mm Rotors ($23)

Yet the adapter alone for the rear brake on this build cost more than the complete brake set. Oh, and one other thing, when you’re building an e-bike, and especially when you’re upgrading your brakes, be sure to buy a new set of cables (incl. a cable cutter tool if you don’t have one).

So let’s talk a bit more about brake tech. Above, I introduced caliper brakes, and hydraulic and mechanical disc brakes. As you can imagine, there are many price points and designs to consider when you’re shopping for brake parts. There are also different disc diameters to consider. I went with 160mm discs front and rear, but on many e-bikes you’ll find a larger diameter disc on the front for more braking power. These discs can be 180 or 203mm in size. Larger discs require different spacers to move the brakes farther away from the hub. Just something to consider.

In theory, hydraulic disc brakes provide better stopping power with less effort at the brake lever. This is true, but you’ll need to decide if the upgrade to hydraulic disc brakes is worth the extra cost. In addition, hydraulic disc brakes come with their own brake levers and brake fluid reservoirs, and they’ll likely need more maintenance than mechanical brake systems. And e-bike brake levers usually have a motor cut-out switch built into the brake lever. The levers that come with your hydraulic brake kit won’t have this feature. I was able to add a switch to my hydraulic brake lever with some effort, but this is not optimal.

One last thought on disc brake systems is that you’ll need to think about replacement brake pads at some point. The mechanical brakes I bought say they use a “Universal Brake Pad compatible with Shimano Deore M515/M525/M475…”. So when you’re shopping for new pads, be sure the pads you buy are compatible, and have a good rating. In all honesty, when I bought my first hydraulic brake system, I didn’t even think about brake pad compatibility, so now I’m curious what pad that brake uses. Hopefully, having read this, you’ll be better informed.

** Update **

My first DIY e-bike is working great EXCEPT for one thing – the rear caliper brake stinks! There seems to be a bit of metal caught in the rim that makes a weird sound each revolution of the rear wheel when the rear brake is applied. As you might recall, I had converted the front brake on this bike to a hydraulic disc which I absolutely love. The rear brake I left with the original caliper since most of the braking is done with the front brake. Anyway, something needs to change regarding the rear brake, so this is what I’m doing.

I ordered a mechanical disc brake and floating 160mm disc for the rear. Here are the parts and images. I’ll provide a picture below of the completed modification and my first impressions once the upgrade is complete.

Total outlay for this mod is $38+tax. I think this will be a significant improvement to my rear braking performance (and it’s red – that’s important!).

** Update **

Having received both the disc and brake, I realized I also needed a disc brake adapter for the Trek frame. Add $25 for that. Then I needed some new brake cable housing (plus $9). SO, now my brake mod adds up to $72+ tax. And yes, it’ll be worth it (picture to be provided when the mod is complete – tomorrow).

And I learned something new today – from YouTube of course! This video covers disc brake adjustment procedures. Interestingly, I sort of figured this out myself, but if you’re new at this, I think this video is a great place to start.

How to Align a Mechanical Disc Brake on a Bike

It’s tomorrow today, so here’s the picture I promised:

Talking about bicycle/e-bike wheels, tires and tubes might not sound so interesting in the scheme of things, especially since I have yet to talk about brakes (equally as important as tires, and the topic of my next post). But I think tires, and their supporting cast, wheels and tubes, are extremely important! And here’s why…

Electric bicycles are heavier than regular bicycles, tend to go a bit faster than a bicycle under pedal power only, and in some cases (to be explained), the rear tire might be considerably harder to change ‘in the field’ than a standard bicycle tire. But we’re getting ahead of ourselves.

Let’s start with wheels. Wheels come in many sizes. My current e-bikes all have spoked 26″ wheels with a 1.5″ width rims. This wheel size has been around a while, so it’s likely you’ll find 26″ wheels if you’re hunting for an older frame to build out an e-bike with. More modern mountain bike wheel sizes include 27.5″ and 29″.

As far as wheel widths are concerned, for mountain bikes and for my DIY e-bikes, 1.95″ to 2.5″ wide tires are the norm. I tend to stick with 1.95″ tires since most of my riding is on paved trails and roads. This tire provides less weight and rolling resistance, but is wide enough to provide a good contact patch on the road surface. I also tend to go with a Slick Wire Bead tire like this one, rather than a traditional knobby mountain bike tire.

Slicks make less road noise and stay planted on a paved road surface better than knobbies. I’m also not a fan of fat-tire e-bikes which can have tire widths up to 4″. For better handling and control, there’s a category called ‘plus-size’ tires which fall into the 2.4″ to 3.25″ range. The popular Rad City 4 Commuter runs the Kenda K-Rad 26″ x 2.3″ which I would consider a plus-size tire on the lower end of the scale, and is an excellent choice for this type of e-bike!

Getting back to wheels for a moment, it should be obvious that your wheel size is going to dictate your tire size and choices available to you. Fitting the wrong size tire to your wheel will have unfortunate consequences!

Once you have settled on a tire size, you’ll need to find tubes that work for your given wheel and tire. Here’s where things can get interesting. First, some wheels are designed for Presta valve stems and some for Shrader value stems. Presta (on the left) is slightly less common on mountain bikes these days than Shrader (on the right, and what you’ll find on your car as well). But still, you have to know which valve type your bike requires before ordering new tubes.

Second, when talking about Shrader valve stems, you’ll need to know if your wheels are single or double-wall (very common on the rear wheel of a rear hub e-bike). As it turns out, rear-hub e-bikes can create a lot of torque, so e-bike manufacturers will use double-wall rims for added strength and durability. But why does this matter you might ask when shopping for tubes? Because you’ll need to buy a tube that has a longer valve stem for a double-wall rim than you would for a single wall rim, resulting in a valve stem that’s too short to connect your air pump to. Here’s a typical tube that works with a single wall rim:

The description doesn’t say how long the valve stem is so it’s likely about 34mm long and won’t work with your double-wall rim – too short. So with a little more searching, you’ll find something like this:

This tube has 48mm Shrader valve stem and will work great with your double-wall wheel(s).

On my DIY bikes, I’m running single-wall wheels on the front so a 34mm stem works fine. However, if you’re in the habit of carrying a spare tube with you on your rides, be sure to carry a tube that will work for either wheel.

As a parting thought, I’m not sure I would actually be able to change the tube on the rear tire of my rear hub e-bikes when I’m out and about. This is because the axle bolts are torqued down and require a wrench (that I don’t carry with me) to remove, AND disconnecting the wires necessary to remove the rear wheel is very cumbersome. I learned all this because I actually got a flat on the rear tire on DIY Build #1, just not while I was riding, thankfully. So what to do?

1. I’m now installing Slime tube protectors in each of my tires – which might help,
2. I carry a bottle of Slime Tube Puncture Repair Sealant, a Shrader valve tool, and a tire pump in my Camelbak pack as a get-home strategy for my rear hub bikes, and
3. I carry a charged cell phone to call home for a lift if necessary (or for other emergencies).

PS – When riding the mid-drive e-bike, I carry a standard tire repair kit since the front and rear wheels are easily removed so tires and tubes can be repaired. The essential ingredients of this repair kit include:

• 3 tire levers
• 1 tube (Presta in this case)
• air pump

** Update **

A couple good videos concerning tires and tubes (specifically about how to prevent flats):

Which size should you have? Electric Bike Tires Explained

Put a STOP to flat tires – 5 things to know for your ebike

As I was writing the previous post about car racks suitable for e-bikes, it occurred to me that I need to also talk about the best ways to secure your e-bikes when mounted on a car rack, as well as when you’re out and about. It’s a fact that e-bikes have a habit of disappearing when you’re not watching (and sometimes when you are). So what to do…

This discussion will include six recommendations, each of which will help you secure your investment, but when used in combination will require the would-be thief to be ever more determined in their quest to separate you from your e-bike(s).

Whenever we talk about security, we have to separate potential thieves into two categories. The first category is the ‘opportunistic thief’. This is the person(s) who see an unlocked/unattended e-bike and walk off with it hoping nobody noticed. In this case, the trusting e-bike owner lost their treasure by not taking proper precautions. Bottom line: If you’re going to be out of sight of your e-bike, at least lock it to something so you have some assurance it’ll be there when you get back. Please!

The second category is the ‘determined thief’. This person has some skills, equipment and experience to defeat just about any security measure you want to throw at them. So let’s not make it too easy for them. The recommendations provided below will hopefully not only deter the opportunistic thief, but also encourage the determined thief to move on to seek easier prey.

Recommendation 1 (assumes you’re using a hitch-mounted e-bike rack):

Use a hitch receiver pin lock like this one: MaxxHaul 70050 Heavy Duty 5/8″- Hitch Locking Receiver Pin

This will save your expensive e-bike rack as well. Start here!

Recommendation 2

Buy a rack that has a built-in locking mechanism, like this one: YAKIMA, OnRamp, E-Bike Hitch Bike Rack

The description says it has ‘Integrated SKS (Same Key System) locks included to secure bikes to rack and rack to vehicle receiver’. You can see how this security feature works at 4:30 in this video – Yakima OnRamp Hitch Mount Platform Bike Rack with Ramp Overview. FYI – This video also covers the ramp option available with this rack starting at 5:55 here.

Recommendation 3

Buy a good lock for your e-bike (AND USE IT)! Here’s a good article on the topic: The 17 Best Bike Locks for Security in Every Scenario. The author divides the various lock types into four catagories:

– Best U-Locks

– Best Folding Locks

– Best Chain Locks

– Best Lightweight Locks

Having just read Dan Roe‘s article, I would probably buy this lock: OnGuard 8019L Mastiff 6′ x 3/8″ Quad Chain Lock

AND a cheap lock like this: Master Lock 8170D U-Lock Bike Lock with Key

The expensive chain lock is used when the bikes are on the car rack, and the el cheapo U-Lock is used when I stop by the library for 5 minutes. The chain lock is heavy but deters the determined thief while the cheap, lightweight U-lock deters the opportunistic one.

My last three recommended security devices have their place in certain situations. Here they are: cameras, motion detectors, and bicycle locators.

First, cameras. If I owned an RV, which I don’t, I could use something like this to monitor my e-bikes: Garmin Dash Cam Mini 2, Tiny Size, 1080p and 140-degree FOV, Monitor Your Vehicle While Away. It’s small and discreet, though it does require a power source and a Wifi connection to do it’s job. Still, I can see this being a very handy device for RV campers in places where e-bikes are known to disappear.

Second, motion detectors. The camera just mentioned does capture video when motion is detected. This is a great feature! But there are also times when you just want to park your e-bike and don’t want anyone to mess with it. I like this gizmo: Juiced Horn/Alarm. When the ‘alarm’ function is armed, the horn will beep whenever someone moves your e-bike. Here’s a video that shows how it works: Demo of the Juiced E-Bike Horn/Alarm. And if you want to save a little money, this one available on Amazon appears to be the same unit for less.

And third, bicycle locators. I’m sure you have heard about Apple’s AirTag. Perhaps you even have you doubts about this product due the AirTag ‘stalking‘ claims that have appeared recently. Still, I think this is the way to go if you’re thinking about putting a ‘tracking’ device on your precious e-bike. Once you have purchased your AirTag here, go here to get a $10 bicycle mount that will secure your tracker to your bike. With this setup you will have a better chance of recovering your wayward e-bike than without it. But note, AirTags are designed to work with Apple iPhones. What about us Android users?

I’m going to say for Android users, consider buying a GPS tracker like this one: Invoxia Cellular GPS Tracker. The upfront cost is $129 which seems a little high, but the recurring monthly subscription cost is quite reasonable at $2.49/mth ($29.90/yr) for 4G-LTE Cat-M1 cellular access. Other features of the Invoxia Tracker include ’tilt detect’ and ‘movement detect’ alerts. If you want to learn more about this cool device, check out this video. Now to figure out where to put this nifty gadget. I’m guessing it’ll go inside my tool bag with Velcro strips. Then I can move it from one bike to the next as needed…

Well, that’s it for this post. But if you’re interested in some more information on this topic, feel free to check out these videos:

How to Protect Your Electric Bike from Theft

Apple’s AirTag Saved My Bike (Real Theft)

GPS tracking: The answer to bike theft?

Thanks for listening!

PS – And another data point. Did you know “over 2 million bikes get stolen each year in North America” and “eBikes being three times more likely to be stolen than a standard bicycle“? (source) Yikes!