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Can 350w 36v decently carry a 280lb guy?

S

sfynzy

100 mW
Joined
Sep 2, 2013
Messages
47
Location
Secret South East Asia Country
A while back, I embarked on a mission to built my own ebike. A lot of people were helpful in answering my questions and I was so ready to bite the bullet and get my ingredients together. But alas, because of the laws in my location, I was not able to build one without risking legal ramifications. It would be easier if there weren't any importing involved.

Anyway, recently I discovered someone selling an ebike that sparked my interest. It is specced 350w 36v, I was wondering if this would be strong enough to carry me around at 280lbs without looking hilarious? It's "maximum load" is supposedly 265 lbs so already I'm over the max but I can lose the weight eventually.

If you look at my past post, I used to be 250lbs. I underwent surgery which halted much of my diet and exercise (EXCUSES!), but that is another story.

I would try the bike myself to see how it goes but I thought I'd ask the knowledgable folks here first so I at least have an idea what to expect.

ps: it is brushless hub motor, rear wheel, lithium.
 
Not very well, no. You realy need a 500 watt motor.

But there are options.

The amount of power the motor puts out is controlled by the controller, not the motor. The motor's rating is about what it is capable of handling if given enough power.

For example: it takes roughly 350 watts for an average rider to go 20mph on flat ground. A 250 watt motor can put out that 350w needed if the controller will let it, and cruise along for a while before over heating. The 350w motor will do the same thing but won't overheat. A 500w motor will also cruise along putting out the 350w needed for 20mph, but with even less stress on the motor.

Now imagine you try this with a heavily loaded bike, going up a long hill. Lets say this hill is causing the motor to pull 1000 watts for 30 minutes as you go up it. the 250 watt motor will overheat and die in just a couple of minutes. the 350 watt may do it a few times, but eventually the stress will cause it to fail. The 500w will shrug it off and keep going.

Motor ratings are sort of ambiguous. If you operate your motor within the requirements of the law, then the motor will be whatever the law required it to be. If you run a 500w motor with a controller set for the speed restrictions of your country, then it will act like a 350 watt motor but have the survivability of a 500w motor

The thing to do is not worry about it, get a larger motor, and then operate it in a safe manner so you don't draw attention to your self.
 
It will struggle like hell to carry you up a steep hill, or into a very strong wind. So try to avoid that till you get strong again.

But it will help. Find flatter places to ride till you lighten up more, and churn those pedals even if it's just faux pedaling, just flapping the legs.

You gotta start someplace, the ol long journey one step at a time. Start by riding as long as you can, with what effort you can put in. Then gradually, start setting the throttle at 15 mph, then try to pedal up 2 mph more. Build from that, keep increasing the effort of your rides without making them so much effort you stop early. Buy another battery if you need to, so you can make those rides 1 hour long, or take 2 half hour rides a day. 30 min is the minimum time.

Just flapping the legs will turn up your metabolisim, so start with that.
 
You'd be surprised how helpful a 350 sized motor is @36v & 15-20amps. Enough to give your legs a decent push at dead stops yet keep your physicality of bicycling when at the motor's RPM range. You'll go farther than you've ever bicycled with the help. Farther distances & longer duration. Before you know it, the pounds/kilos will start to fall.

You could still do it on a more powerful setup, but it's easy to let the motor do most of the job. :arrow: Use what you have already.
 
350W will not carry you very fast. Big deal. Remember the motor's 350W is something you can add to whatever power you make at the pedals. E-biking around without pedaling won't get you in better shape, no matter what speed you are going.

My main concern is the effect your weight will have on the typical sub-minimum quality e-bike rear wheel. For a motor of less than 1hp (750W), it is a better idea to put it in the front so you can keep more structural integrity in the rear wheel. At your weight, I found I had to use very sturdy wheels on my pedal bikes to get decent reliability out of them. Now I weigh even more, but I have only used my own specially built wheels for many years.
 
You'll certainly want more power.

Think about a MAC motor build. That motor carried me around at 20-38mph for 3 years, including up steep hills when i was 270lbs.
 
Depends on how much you like, or are capable of, pedaling. I, for example, have a 250 watt hub motor (36 volt battery) on my recumbent tandem trike: the weight of the two of us combined is a little over 300 lbs, and with the weight of the bike, the whole rig (minus touring gear, mind you) is close to 400 lbs. Our hub motor does fine in helping us up hills, but we like to pedal and would never--short of serious injury--depend solely on the motor to propel us. In fact, since the motor's top speed is only 12 mph (16" wheel), we don't even use it if we're able to go faster than that under our own power. If you're capable of and willing to assist by pedaling, in my inexpert opinion, this bike could work for you.
 
well, here is my 2 cents worth. I am 260#, I have 7 ebikes and 8 other kinds of pedal bikes. I have various motors,a couple Bafangs, a couple ebikekit motors, a 9c, a 9c clone(Yescom) from that place in California and a cutie 100. voltage vary from 24v to 72v on the motor, using them as rear drive or front drive. I have progress in batteries from sla in the beginning, to lifepo3 for a year and last couple years it has been LIPO. On all bikes I run dual packs of 12s 10a. I know Chicago is flat, I over volt all the motors to approx 48v-52v, even did 72v a few time, but I settle down to 48v that I use on all the bikes, which was good enough for me to get to the mid 20's. All the bike share the common dual 12s packs. even the cutie 100(350w 36v), on dual 16" wheels(my signature) will get to almost 20mph. those motors are more powerful than you think. Last year on the our Outer drive ride, my 9c clone was passing up a lot of roadie bikes, some tried to catch up. so I think you should be ok. Unless you are in competition, you really don't need to go much over 30mph, because it is scary, unless you want to join the 50mph club, the get a decent controller and feed about 76v-100v, make sure your bike can stand the stress.
 
Thanks for the valuable responses everyone. Seems that there are some differences of opinions but that could be because people have different idea of what "decently carry" might mean, so that is my fault for not being more specific. Nevertheless, thank you!

DAND213: It is lithium battery. Sorry I did not know that it makes a difference.
 
sfynzy said:
Thanks for the valuable responses everyone. Seems that there are some differences of opinions but that could be because people have different idea of what "decently carry" might mean, so that is my fault for not being more specific. Nevertheless, thank you!

DAND213: It is lithium battery. Sorry I did not know that it makes a difference.
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It depends on which way you are going, from a pedal only bike to a 350 watt e bike could be a pretty good jump up in performance, from walking to a 350 watt ebike is a quantum leap.

If you are going the other way, from a car or motorcycle a 350 watt e bike is likely going to be somewhat frustrating.

Terrain and your expectations count for a lot, 350 watts isn't going to like hills much, particularly if you don't pedal fairly hard, you can smoke the motor and hurt the battery in less than an hour doing it wrong.
 
What are the limitations on the power of the motors where you live? You could always go with both a front and rear kit. I think the limitation is per motor.
 
Hi guys, I decided to go with a scooter instead! (the kick scooter type kind). It's also powered at 350w 36v, and so far it works fine for me. As mentioned in one of the responses, it's a step up from manual cycling. Can't tell you how happy I am after months and months of reading about electric bikes, I finally get to ride one, though its a scooter. I am now confident of the power it has, so at least now I can be sure if I built a 350w bike it won't be a waste of time! So happy thanks u guys. I know this is off topic but.. do I charge my battery after every ride out? Or do I let it drop at a low level first then I charge it? I read some articles on it and it seems that it's not advisable to let your battery (lipo) energy go down too low and that u should stop using your vehicle once u see that it's slowing down. But the article didn't mention (or I didn't notice) whether I should charge after every use..
 
Charge every ride, and if you have lead batteries, charge it immediately.

Glad you hear you have an EV grin, even if it's only a 350w grin.

Not so glad you aren't at least faux pedaling. Eventually get that ebike, so you can gradually improve your health, and likely lessen your weight.

I ride for lots of reasons, the first reason just being fun. But the beneficial effect on my health is the second one.
 
Thanks for the response dogman!

Oh no, I didn't charge it after riding just now, I only rode for a bit though (to get the hang of it). None of the battery bars are gone yet, would it be terrible if I not charge it after riding only for a little bit?

Most of the eBikes available in my area are sla powered, so it looks very obvious that it's an eBike (I prefer stealthier). And the ones that are lithium powered can be pretty pricey (the one i was considering).

However! I've found a local conversion kit!

One is a rear wheel 24v 250w, and another is a front wheel 36v (not sure what watt but I think 350).

My manual bike is an aluminium frame, with alu fork. From what I've read front wheel motors can be a dangerous thing so that's kinda what's stopping me from getting it. Steel forks aren't that easy to find it seems lol.

I might try to find someone around here with a 250w powered EV and see if they would let me try ride it to see if it's ok for me. I really don't need to go super fast. Just enough to assist in pedalling as you said.
 
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