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08-02-2018, 03:03 PM | #1 |
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The Electric Bike Thread
I've been building electric bikes for a few years now but just as a hobby. Here is a brief FAQ:
Do you get a workout: --You can get a hell of a workout, see below Do I pedal: --No. On the second bike I posted you'll notice the pedals aren't even connected. These bikes are basically ultralight motorcycles with a stealth aspect. Can you pedal: --Absolutely! You can setup these bikes so that the motor provides a boost to your natural pedaling, but I'm not into that currently. How fast: --Slowest bike I have goes 40 MPH (4KW input power) --Fastest bike I've built did 70 MPH (16+KW input power) How far: --Depends entirely how you ride, and how fast. You could go 10 miles or 50+ miles on the same pack. With a 15lb pack I get about 20 miles of fast trail riding with a top speed of 30-35 mph. How much: --For decent equipment and a good battery, $1500-$2000 without the bicycle itself is a bare minimum Where: --ANYWHERE. With a good judgement cops ignore you and you can ride in parks and public places where motorized vehicles "aren't allowed". And of course you can ride on the street. Almost nobody thinks a bicycle going 45 mph is a big deal, because nobody rides bicycles. Why: --It's fun, and if you ride trails, it's a great workout. Fitness: --No, really. Riding trails is a ridiculous workout. You have a bike that weighs 60-90 lbs and you're going much faster than you would if you were pedaling. It's very easy to ride at the lactic threshold. Pics: Downhill bike with approx 4hp output. I mounted a larger battery with 1KWh usable capacity on the top tube and replaced the controller with one much smaller since this was taken. Current top speed of ~40, although in the configuration shown it did 50+. Bike with custom swingarm I fabricated. In this pic it has a motor with approx 6hp output (6KW input). This bike will do 50+ MPH in this configuration. I had a larger motor with approx 15hp output which let me get to 70 MPH. I removed that motor because it was way too heavy and the handling sucked. Vid of me riding. It's harder than it looks! Power output really limited in this video due to overheating. So yeah anyone else riding electric bikes of any kind? They are way too much fun. Last edited by The Wind Breezes; 08-03-2018 at 02:30 AM.. |
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08-03-2018, 02:01 AM | #2 |
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I really like bikes you’ve made. The look rugged and sturdy. Are You marketing your product? If so...where.
These things are a kick in the butt to ride and don’t let anyone tell you you’re not getting a work out. You can pedal these things much as you want. The trick is to know when to let the bike do the work. I’m starting to see more of themaround too. Thanks for starting a cool thread c |
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The Wind Breezes918.50 |
08-03-2018, 02:17 AM | #3 | |
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I don't pedal these bikes at all, the workout comes from throwing the bike around on the trails and constantly moving up, down and around on it as we go around corners and over obstacles. It's very hard work. Electric bikes are so much fun, I'm honestly at a loss why the streets aren't filled with them. I guess there are a variety of factors: cost, general lack of interest in the outdoors, lack of interest in physical activity in general, lack of ability to ride an illegal bike confidently without getting busted, lack of knowledge that these things exist or that they're freaking awesome. |
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Sea-Tac1448.00 |
08-03-2018, 10:14 AM | #4 |
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Thanks. I’ve seen people riding these down in San Diego and various beach communities in So Cal. I’ve also seen them up here and in Portland. I really think we are seeing the leading edge of a popular mode of transport yet to come. I would suspect we’ll start to see these as city “park anywhere” bikes that people rent by the mile or hour.
In any case I think your bikes are cool. Thanks for the info. |
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The Wind Breezes918.50 |
08-03-2018, 03:08 PM | #5 |
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Come one, come all, come ebike owners. There have to be several people who own some nice pedalec bikes like Trek or Bulls on here. Share your experiences with the bikes and how you use them.
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08-04-2018, 09:23 PM | #6 |
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I converted an old MTB over a few months ago.
I like riding my pushy but where I live there are too many hills which spoils the fun for me. So far I've had no problems with it but it is a relatively modest 3kW. I was looking at a scooter originally but these are illegal to ride on anything other than private land where I am so the ebike is great way to get up to the shops for those small errands. |
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The Wind Breezes918.50 |
08-04-2018, 10:06 PM | #7 |
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I was doing a ride with some friends through Glenwood Canyon. At Hanging Lake I spotted a couple of electric bikes sitting beside the trail. Then I saw the riders, both north of 300lbs. Good for them but I think I'll keep peddling.
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08-05-2018, 11:12 AM | #8 | |
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Also, the idea that electric bikes make things easier is a huge misconception. If you are riding on a smooth road with just the throttle, yes, it is easy. But nobody is making you do that. If you are riding with the throttle on trails and trying to go fast, you will quickly work your way up to your physical limit with a bit of skill. That riding is every bit as hard as pedaling, and more of a full body workout. Finally, nobody says you can't pedal a push-assist electric bike as hard as you want. You can, and the advantage is you will go a lot faster for a given level of exertion. Not to mention there are varying levels of assist. The last point seems an extremely obvious conclusion for anyone who's ridden a bike for a while. As you get physically stronger and faster, you don't just sit around and ride at the same speed, doing less and less relative work. Typically you push yourself so that you're working just as hard, and getting more out of it. |
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08-05-2018, 11:36 AM | #9 |
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Yea, I've ridden a bike for a while, longer than I care to admit. Sure you keep going faster until it gets hard. Where I live we're lucky to have a fantastic bike trail system. The last thing I want to see is a bunch of e-bikes going 35-40 mph on the trails.
I don't mountain bike anymore. I can see the e-bike benefit in the dirt but I could never relate to the full armor, go faster 'till you crash set. I can't get past the chicken and egg thing. Since the e-bikes weigh a ton you need the motor. If having the motor just lets you stay closer to the edge of crashing more often then I'm glad not to be sharing the trail with you. Have at it. My point of the 300lb guy sort of relates back to skiing. Back i the 70's we all skied on long, skinny skis. On a big powder day 80% of the people stuck to the groomed trails, leaving the rest for the skilled. Today, fat skis bring everyone out to ski powder. In some resorts untracked lasts about a hour. Will e-bikes fill the trails with the unfit, unskilled? Is that a good thing? For whom? |
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08-05-2018, 12:15 PM | #10 | |
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Will ebikes bring the unfit and unskilled to the trails? If they do, I can only see that as a good thing because those people will be getting exercise and exposure to the outdoors. Your concern for unfit and unskilled people hauling ass on ebikes is completely unwarranted. They couldn't do it if they tried. Bikes are very self correcting because you will crash very quickly and teach yourself a lesson if you ride over your head. And if you're unfit, you won't be able to ride hard for long without getting winded and needing to slow down. |
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08-06-2018, 08:36 AM | #11 |
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So a completely unrelated question. When I first started looking into ebikes I saw models claiming 250-1kW power levels. Given the common use of 18650 cells that made sense to me. You claim 4-16kW of power. Could you fill me in on the details? An 18650 cell can deliver about 6W so that would be 2666 cells for 16kW. You must be doing something different.
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08-16-2018, 03:04 PM | #12 | |
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18650s have capacities around 9-11 WATT-HOURS for a 2.5-3Ah cell. That's the energy density. Power density will be around 10x higher--good cheap cells like the Samsung 25R can discharge 25 amps, slightly more for very short periods. That's a discharge rating of about 10C or about 90 watts per battery with a nominal voltage of 3.6 volts. You would deplete the battery in about 6 minutes and it will be very hot, but real world use is considerably more tolerant. A ~1KWh nominal capacity pack with good cells can output about 10KW for short periods on a fresh charge. You can lookup a datasheet for any given battery and it should have discharge curves at different power levels. Also I don't screw with 18650 anymore, I use high discharge RC LiPo and drain them to about 20% of capacity. Much higher average discharge voltage, and way easier to configure a pack (no laborious spot welding needed). Thanks Last edited by The Wind Breezes; 08-16-2018 at 03:10 PM.. |
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08-16-2018, 03:11 PM | #13 | |
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The Wind Breezes918.50 |
08-16-2018, 04:58 PM | #14 |
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03-13-2019, 10:43 AM | #15 |
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I want this with upgraded suspension, brakes and tires!
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The Wind Breezes918.50 |
10-12-2019, 12:20 PM | #16 |
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Anyone here with an electric bike figure out how to load it onto their F30? I'm considering getting one and wouldn't need to put it in the car very often, but a lot of the racks I've seen have a max weight that's too low for many ebikes.
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10-15-2019, 03:09 PM | #17 |
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2 or 3 bay bike rack shouldn't have any problem holding a single ebike on the closest bay to the car.
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10-26-2019, 02:54 AM | #18 |
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Wow, you have some serious performing ebikes, I dig em.
My gf and I bought some Swagtron (dumb name, I know) EB5 and love them! Cheap and have been reliable for over a year now. We pedal 75% of the time and use electric power when we get tired or just want to have fun. Best of all, it fits in my trunk! |
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