Stealth Electric Bikes

STEALTH: A View From Behind Bars

By October 3, 2014 B-52, E-Bike Technology

A new Stealth customer takes us on a factual journey through B-52 Bomber ownership, and in doing so, highlights just why our e-bikes are leaving the competition in their wake.


It was in February of 2014 that Australian customer, Ricc Storti, placed an order for his Stealth B-52 Bomber. An experienced electric bike pilot who had in the past produced a custom hybrid e-bike of his own, Ricc was looking to take the next step in quality and adjustability: he was a seeking a more advanced battery management system (BMS) than he could develop with his own hands, a more robust and durable battery, and more scope to tweak power outputs based on his mood, which, for the record, ranged from “quiet commuter” to “full-throttle assault”.


Now, Ricc is also someone who is not afraid of calculations; he understands range and power outputs, is inspired and intrigued by technology, and accordingly, was willing to spend the time computing just which e-bike would best meet his requirements. Ricc was able to calculate that his B-52 Bomber could take him some 160km when set at 250 Watts and relying on pure electric power, and that at 1600 Watts, it would already be accelerating so quickly that his legs would be physically incapable of keeping up. And, in reality, Ricc was right… At maximum power, he claims to be frightened of the performance (in a good way, of course!).


What makes the B-52 particularly appealing, says Ricc, is that inside the 250 to 1500 Watt range, it offers the perfect fusion of pedal-power and electrical assistance, finely balancing his desire for a cardiovascular workout with a New World edge. Beyond 1500 Watts, he says, the B-52 becomes a motor bike with a difference, crossing into the realm of “the immensely powerful – almost too powerful”, where the thrills are unparalleled.


For most riders, says Ricc, “1500 Watts is as much as they might practically want”, yet the notion that the B-52 kicks out some three-and-a-half times this, is one that Ricc still welcomes, purely for the “fun of having an immensely powerful beast between [his] legs”.


And, beyond the accelerative thrills, Ricc was keen to touch on the advantages of his B-52’s regenerative braking technology, noting that the system is “absolutely marvellous, not just because of the energy capture, but also as a great braking device”. Stealth’s re-gen system is designed to integrate fluidly into the riding experience, enhancing battery range, whilst offering a seamless engine-braking effect, which reduces riders’ “arm pump”, especially on steeper and more demanding trails.


It is the technological advantages like these, borne out of Stealth’s ongoing investment in worldwide R&D, that are the hallmark of each and every one of its bikes. And, in support of these efforts, Ricc goes even further, advocating the variable power outputs, managed by Stealth’s proprietary BMS, which works in conjunction with the DC-1 Stealth Management System. The DC-1 is a multilingual display, offering twin trip meters, a range estimator, system diagnostics, ride efficiency calculator, average speed, and more. It even calculates the total recovery yielded by the aforementioned re-gen braking system. Perfect for riders like Ricc who are passionate about the technology, but also attuned to its technical advantages.


“We’re proud that our customers – like Ricc and many more – are genuinely using and benefiting from the features we build into our bikes,” says Stealth’s managing director, John Karambalis.


“It’s all well and good to build high-end products that last and deliver the thrills our customers expect, but we also strive to lead the technological charge in the electric bike world, and our DC-1 and the associated regenerative braking system, are critical parts of this aspiration. All the feedback we receive on these (and our bikes overall) is exactly what allows us to further enhance them. This is just one of the reasons we always look to build a relationship with our customers. No matter how many bikes we sell and distributors we sign up, we’ll always retain our boutique feel.”


And this is just how the Stealth experience goes further than the bike, adds Ricc himself (who, by the way, also wanted to point out that people stop him in the street to photograph his bike), for “the customer and technical service and support from Stealth Electric Bikes is”, in his own words, “superb and super-fantastic”.


In signing off his letter to Stealth, Ricc had one last line of praise for his B-52 – something that he shares with every Stealth rider worldwide – and that is the sheer aesthetic appeal of his bike. In his own words, “it looks like it comes from the Bat Cave”.


Good thing it has the technology to match.


Riccardo Storti is a genuine Stealth Electric Bikes customer, and one that wrote to the company on his own accord – Ricc’s original letter is published below. Stealth is proud to say that all the quotes and statistics published above are Ricc’s own words, and that this article was written with Ricc’s permission. Stealth openly encourages customers to book their own test ride and find out just what Ricc is talking about. 


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The Original Letter from Riccardo Storti

G’day Everyone,


I ordered my Stealth Bomber on 20-02-2014 and received it about 6 weeks later (I think, can’t remember exactly). The reason I purchased the Bomber was because I wanted a dirt bike experience, but hated the noise generated by the petrol models. The tinny, twangy sound of a petrol dirt bike bothers me, so the Bomber was instantly appealing. Moreover, I wanted to be as green as possible, but not compromise on the dirt bike experience I was seeking. In addition, I’m a keen cyclist and cardiovascular fitness is extremely important to me, so the Bomber seemed to fit all my requirements. They’re not cheap, but I was willing to take a chance and I’m very glad that I did.


I’ve undergone somewhat of a physical transformation in my life and it was quite a journey; this is an important story (in my opinion), so please bear with me and keep reading. At the time of writing this, I am 46 years of age, I weigh 75kg, am 175cm tall and wear 30” trousers around my waist. However, six years ago, I was 124kg and wore 42” trousers. I managed to lose 56kg, down to 68kg, then up to 75kg because at 68kg I was carrying about 5% body fat and would nearly faint; at 75kg, I’m about 7% body fat, so, why is this important? …. Good question, I’m glad you asked … The answer is because I learned the need for cardiovascular exercise during my transformation process …. No, I didn’t lose this weight from the Bomber, I lost it by power walking one to two hours every day, carrying a 25kg backpack stuffed with books and dinner plates. However, this practice gave me a sore back and my doctor suggested to take up cycling instead.


So, that’s what I did; I started cycling as a method to manage and maintain my weight-loss. However, like almost everyone, I have to work and I needed a cycling activity that fit into my lifestyle. I also wanted a way to kill two birds with one stone, that is, commute to work and get my daily exercise simultaneously. Consequently, I purchased an e-bike conversion kit and commuted to work. After chewing through two e-bike conversion kits (the batteries will tend to last about 12-18 months, no more), and having dealt with an endless stream of electrical problems induced by my own poor electrical wiring skills, I decided to purchase a professionally built e-bike and avoid electrical problems. So, I bought an OptiBike R1100 and a Stealth Bomber. Why both? …. Again, great question and I’m glad you asked. I have 6 bikes all up and each one gives me a different riding experience: a bike is not [“just”] a bike, they’re all different and provide different kinds of fun. I have four regular bikes and two e-bikes – each one is very different from the next. The OptiBike is a push-bike for a cyclist, the Bomber is a push-bike for the dirt biker.


Here, I’m going to talk about the Bomber specifically. Firstly, I need to make some statements about e-bikes in general. It has been my experience that they are widely misunderstood as being a form of “cheating” or “easy riding”. This is absolutely ridiculous, so much so that it isn’t even wrong, it’s just childish and reflects a complete lack of understanding of fundamental physics. As I mentioned above, I take weight-loss and weight management very seriously, and I have recorded thousands of measurements (literally) regarding my energy expenditure during power walking and cycling. Here’s what I’ve found:


  1. A person on a regular bike works longer, NOT harder.
  2. Cycling is twice as energetically intensive as power walking (over a fixed duration).
  3. The human body outputs a constant amount of energy (an average) per hour of cycling exercise; for me, it’s about 520 (Cal / hr).
  4. Each person has their own comfortable state of cycling exercise; for me it’s a heart rate of about 130-135 beats per minute (BPM) and a cadence of about 70-75 revolutions per minute (RPM).
  5. The “comfortable state of cycling exercise” above is governed by the gearing ratios on the bike being ridden. The point here being that our bodies find what is comfortable and sustainable, and for me, the BPM + RPM yields 520 (Cal / hr).
  6. The energy expended by the rider is overlaid upon the capability of the bike. By this I mean that on my regular mountain bike with knobby tyres, my output of 520 (Cal / hr) yields an average velocity of 20 (km / hr). On my Bomber, I still output 520 (Cal / hr), but I’m traveling at 50 (km / hr) when I restrain the Bomber to 1100(W). In other words, the energy a rider expends does not change per unit time, what changes is the energy expended per unit distance. Therefore, on my regular mountain bike, I will burn approximately 800 (Cal) over 30 (km); on the Bomber, I’ll expend about 520 (Cal) over the same distance … But, I will make this trip in 1 (hr) on the Bomber, and 1.5 (hrs) on my regular Mountain Bike with knobby tyres. For me, 1.5 (hrs) each way commuting to work is too long, 1 (hr) is about the same time it would take me to drive; so 1 (hr) is just about perfect for my lifestyle.
  7. At 250(W), I burn about 650 (Cal) each way to work on the Bomber. This means that I burn about 1300 (Cal / day) commuting round-trip to work; not a bad bit of exercise and I get to eat like 3 horses because of it. I eat what I want, when I want and in the quantities I want. The average male needs approximately 1500-1700 (Cal / day) just to survive in a comatose state (according to the literature I have read and the measurements of energy expended during sleeping that I have made), so my body needs about 3000 (Cal / day) just to maintain my body weight …. To anybody that loves food as much as I do, this is heaven.
  8. I can carry 20-30kg of groceries on my back, and I’m not slowed down in any way. I tend to do my grocery shopping during lunchtime at work and can cart everything back home with the Bomber if I wish to.


So what does all the above mean about the Bomber? Oh, God, I love your questions, well done kids:


  1. From power settings of 100(W) to 1500(W) for me, the Bomber is a very effective cardiovascular workout tool; just like any regular bike.
  2. From 1600(W) to 5000(W) (that’s what the adjustable controller tells me via the user interface), the Bomber ceases to be a push-bike and becomes a Dirt bike ….. Why? …. My God you ask a lot of questions; the answer being that the bike goes faster than I am able to pedal. The 9 speed clockwork sequential gearbox spans the 100(W) to 1500(W) range very well, but because the bike is so immensely powerful, it takes a faster pair of feet than mine to be able to contribute mechanical energy to the work being done by the motor.
  3. When I want to burn energy to manage my weight, I dial-up 1500(W) or less. When I want to have more of a motorbike / dirt bike experience, I tend to run it at 2000(W). When I have urges for maximum acceleration, I run it at 5000(W).


Here’s the approximate range performance you can expect from the Bomber with a full charge (this is a rough guide, subject to many variables):


  1. 250(W) = approx. 160 (km)
  2. 1500(W) = approx. 54 (km)
  3. 5000(W) = approx. 27 (km)


Important notes:


  1. The recharge time is about 3 (hrs) from bone-dry.
  2. A Duro RazorBack will only last about 1500(km) if you ride predominantly on paved surfaces.
  3. If you want to use the Bomber as a commute vehicle on paved surfaces, get the Crazy-Bob tyres.
  4. I am now running a Crazy-Bob on the rear and a Duro RazorBack on the front. A Duro RazorBack on the front gives me front end grip and is long lasting; the rear is a different story.
  5. Personally, I’m not that thrilled with the MT2’s, but that’s just a personal feel preference; I now wish I had of purchased the MT4’s (I may do the upgrade at some point, but I’m still thinking about it).
  6. The regenerative braking is absolutely marvellous; not just because of the energy capture, but also as a great braking device. You’ll be amazed at how quickly it will slow you down, gently, [which is] especially good for the wet in my opinion.


Further observations:


  1. The customer and technical service support from Stealth Electric Bikes (SEB) is superb, super-fantastic, you can’t go wrong.
  2. The bike is immensely powerful, almost too powerful. I’ve never had the courage so far to run it at top speed. However, the variable power output is the perfect solution. I’m guessing that for the majority of riders, 1500(W) is as far as they might practically want. Nevertheless, if you want to run higher power levels, you can.


Things I would like to see SEB provide to the market:


  1. A charger for the car (if practical). Sometimes I like to take the bike bush with my father (he goes fishing, I ride); a car charger would be good for me (assuming it’s practical to do so).
  2. Bluetooth connectivity to my iPod Touch. It would be great to be able to feed all the data that the on-board computer logs to a spreadsheet.
  3. An external Battery Management System (BMS) reset switch (waterproofed) … Why? …. Because if you deplete the battery to 0-1(%) remaining charge, the BMS may kill the power in order to protect the battery. This is not a problem, just an inconvenience because the owner is then required to remove a side panel and physically disconnect then reconnect the battery cable in order to reset the BMS.


Conclusion: as I’m sure you can see from everything that I have written above (which took me a couple of hours to compile), I would recommend purchasing the Stealth Bomber for seven keys reasons:


    1. The company service and support is amazing.
    2. As a long distance daily commute vehicle.
    3. As a weight-loss / weight-management tool.
    4. It is quiet, very, very quiet: basically, you only hear the tyre noise, that’s it, nothing else.
    5. Styling: it looks like it comes from the Bat Cave.
    6. It is a head turner, no doubt, no doubt at all: I [even] get people stopping to photograph it.
    7. For the fun of having an immensely powerful beast between your legs.


Cheers …. Ricc