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Electra Townie Go! 250W Cruiser

May 2, 2014
4,294 Views

I am a fan of the Electra Townie. If you want to see a custom project that shows what can be done with a Townie, click here to see a featured custom build by our friend, Nick.

A cruiser style of frame has been around for over a hundred years, but back in 1993, two friends (Benno Bänziger of Switzerland and Jeano Erforth of Germany) noticed that quality-made cruisers were no longer available. They formed the Electra Bike company to produce high-quality cruisers that have a low seat to allow riders to have their feet flat on the ground at a stop, and also…these frames have a comfortable “feet forward” posture that some riders prefer.

Some frames styles have a physical limit on the width of the tires that can be used. One of the characteristics of cruisers is that they allow fairly fat tires to be mounted, and this is very useful for street commuters, because …the real world is filled with potholes and curbs (even though other tires that are thin and high-pressure will reduce rolling resistance). Just having fat tires alone (with no frame suspension components) is a feature that will smooth out a lot of your ride.

One of the benefits of a Townie for an electric bike commuter who might want to ride on city streets at the popular top-speed of 28-MPH (45-kph) is that the Townie frame has a slightly longer wheelbase. This makes it more stable at higher speeds, compared to a more common shorter wheelbase frame. Also, it uses a 1-1/8 inch head-tube, which allows any builder to easily swap-in a wide variety of of front suspension forks, which is a highly recommended upgrade for any E-bike that runs near 30-MPH (or more!).

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Electra purchased by Trek

Whenever chat forums discussed “comfort” cruisers with a feet-forward posture, the names Electra Townie and Trek Pure were often mentioned (Sun Bicycles recently introduced the Drifter and a similar frame is also used by the Giant Suede, plus the KHS Manhattan Smoothie3). Electra managed to patent certain aspects of their frame geometry, and once bikes of this style started to gain a lot of attention, several manufacturers began making models with similar features.

In 2011, Electra filed a lawsuit against Trek because they felt their Pure model was too close of a copy of Electra’s patented features. Trek is a giant global bicycle producer with their headquarters in Wisconsin, USA…and when they felt they would not benefit from continuing to fight the lawsuit…they simply bought Electra. However, this raises the question of whether Trek will continue to make all the Townie line-up, when there are several Trek models that are VERY similar?

For the time being, Trek announced that they will keep Electra’s headquarters in Vista (just north of San Diego in southern California). Trek has a history of buying small bicycle brands that show growth potential, and have a type of bike that will diversify their catalog. So…their purchase of Electra (in January 2014) is not necessarily a bad thing, since it now puts a huge amount of financial clout behind the popular Electra brand.

 

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Can you tell which one is which? The Electra Townie is on the left, and the Trek Pure on the right.

 

I mention the corporate shake-up, because this will put Electra’s first factory electric bike in flux, since they no longer have full control of their future business decisions. This year, Trek is rolling out models of off-road E-bikes with the well-designed Bosch mid-drive, so we know that they understand the value of having electric models in their line-up. And hopefully, Treks experience with electric bikes will lead to an improved version of the Electra E-bikes.

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The comprehensive feature-set of the E-matic system is integrated inside the rear hub to keep the external clutter as sleek as possible.

 

SRAM E-matic

Electra’s first E-bike uses the SRAM E-matic pedelec system. Its only a small 250W rear hub, but it has a patented two-speed transmission integrated into the body of the hub, which is quite a wonderful feature. Other than the charger, there are only two components in this system, and this system leaves the handlebars completely uncluttered with controls or readouts.

The battery slides into the sandwich-style cargo rack (it locks to the rack with a key), and the battery case holds the on/off switch. Then the single battery cable is plugged into the socket of the cable coming out of the left side of the motor. When the power switch is off, this is simply a single-speed beach cruiser with a relaxed posture and fat tires. Once the E-matic system is turned on, it senses your pedaling effort and adds electric power (no hand throttle). If you pedal hard and the bike starts to slow down because of an uphill, the system actually reverses the internal motor, which then engages a second set of gears to the hub-shell output.

This is called a “retro-direct” transmission, and of course the wheel always rotates in the forward direction regardless of the direction the motor is spinning in. This was invented using an external chain to create the retro-direct system back in 1869, and this provided the first 2-speed bicycles. However, the modern E-matic uses internal gears instead of a chain. To be clear, it is the motor that has two automatic internal gears that it uses.

Also, due to the width of placing all four of these components inside the hub (controller, torque-sensor, 2-speed transmission, motor)…the rear hub only leaves enough room to allow a single-speed freewheel at the rear wheel, for the pedals to use.

Because the controller is integrated inside the hub (like the Magic Pie and the BionX-D), this removes much of the external wiring clutter that can make DIY kits unruly-looking. The SRAM E-matic system can also be found on the XU450-E2 from OHM bicycles.

 

 

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Here is the 2010 patent drawing for the two-speed hub motor from SRAM. The Patent EP 2204316A1 lists Brian Jordan of Chicago as the inventor.

This clever retro-direct 2-speed transmission that is being built into the hub motor is an exciting advance, but I am disappointed that they introduced it in such a small motor. I understand that bicycles and E-bikes are quite big in Europe, so it looks like that the EU is its main target demographic.

There is a 250W power limit (and 25-kph speed limit) for street-legal E-bikes in most of Europe (Mountainous Switzerland has a 500W limit). Previous attempts to sell a mild 250W E-bike in North America have not been very successful, since the USA power and speed limit is 750W and 20-MPH. The motors first gear might actually climb hills quite well, because second gear tops out at only 16-MPH (25-kph). You can pedal as fast as you want (perhaps 28-MPH if you are strong?), but the E-matic will only add electric power up to 16-MPH.

Since the typical single-speed Townie retails for around $500, and the electric Townie Go! is listed for $2,200…you are paying roughly $1,700 for a 250W two-speed pedelec system.

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Conclusion

I don’t believe this will sell very well to the public in North America, but I do think this system will appeal to bicycle rental shops. My favorite Local Bike Shop (LBS) here in Kansas has well-paid and very competent mechanics, but many bike shops I have been to, can easily find “adequate” mechanics for an entry-level wage. This E-matic system is easily repaired using entry-level mechanics by simply swapping-in a new hub or battery…that’s it.

Bike shops are having a hard time surviving today, and sending their mechanics to an e-bike troubleshooting course is an expense that many shop owners are reluctant to pay for. Such a shop could see that the simplicity of the E-matic system would be fairly easy to manage, and any shop that continues to ignore all electric bikes may be doing so to their long-term detriment.

Also, even though it now looks like a pedelec might be legal up to 28-MPH in the USA (throttle operation is only legal up to 20-MPH), it might be a liability nightmare for a bike rental place to have customers crashing electric bikes at 20-28 MPH…so 16-MPH is actually a much more reasonable power level for lawsuit-happy customers.

At least this E-bike uses 36V (instead of 24V) to get to the 250W limit, but…since it also uses a proprietary torque-sensing and reversing controller…you can’t just upgrade to an external controller to adjust the amps up for more power. SRAM does not sell the E-matic system as a stand-alone kit (even though the installation is VERY easy), and right now you can only get it on a factory E-bike.

The $1,700 price premium of this bike over the stock single-speed Townie is a big pill to get past, but to be fair, there are other included features. The front wheel has a dynamo-hub that powers a headlight and tail-light, plus this model also has a full fender set and chain guard. A great upscale feature is the Euro-style AXA Solid wheel-lock, and although the bike can still be picked up and carried (yeah, it’s pretty heavy), but it is a fast and easy to way to make sure it can’t be rolled or pedaled away.

This E-bike might actually be selling well in countries with a 250W power limit and a 25-kph speed limit, but the company has not provided any sales figures as to where and how many…

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Some Suggestions…

If Trek and E-matic really wanted to make a splash in North America with this, they should do three things. Move the battery to the frame triangle, increase the diameter of the motor a couple more inches (to increase copper mass and magnet leverage which increases torque), and last…use the extra copper mass from the previous suggestion to raise the power to 750W (48V would be best, but 36V should be adequate, and…a 36V battery would be more affordable). You might add more FETs to the controller to help it run cooler at the extra amps needed to reach 750W, but the larger diameter will give you some extra room inside the hub to do that.

This fully integrated system is very hard to hot-rod (because of the proprietary motor-reversing controller, and how the controller is hidden inside the hub), and it’s about as sleek and simple as a pedelec can be. Because of both these reasons, it would be a good system to allow in some anti-ebike places, like New York City.

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The 36V battery has 7.7-Ah for a modest total of 280-WH. The drive sprocket is 44T and the hub cog is 17T.

The 26-inch tires are Schwalbe Fat Franks, and they provide a classic look in an plush 2.35 inch wide tire that soaks up any minor road irregularities.

 

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The fork is steel for strength, and the frame is aluminum to save weight.

 

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Written by Ron/Spinningmagnets, May 2014

 

Grew up in Los Angeles California, US Navy submarine mechanic from 1977-81/SanDiego. Hydraulic mechanic in the 1980's/Los Angeles. Heavy equipment operator in the 1990's/traveled to various locations. Dump truck driver in the 2000's/SW Utah. Currently a water plant operator since 2010/NW Kansas

  • EdB

    Great drive unit. Love the internal twin gears…I know the wattage is a bit low but it’s doubling the power at your legs, that’s no small thing. Pretty good option for pootling around town without getting sweaty. Looks very stealth and pretty styley too.

  • Ben Munson

    Please read Bicycle Quarterly’s analysis of rolling resistance and tire width. Your assessment of thin tires may change drastically!