Cheapest e-components for 55mph?

[markz]

Obviously the 5K MXUS or QS motors would be the "value" choice to make.

 

[tigcross]

hi beginner01, it's clear that you know what you're dealing with, and I hope some of the negativity posted here hasn't turned you off of this forum.
I'm a big fan of Hub motors for their simplicity and the re-gen breaking, but in your case I'm inclined to say "stick with what you know". Your frames are already set up for external drives, and as I see it you just have to switch from gas power to electric. Why not mount a small BLDC motor on the frame and go with a direct chain drive as you already are on your gas bike? (you could also consider belt drive). As a bonus, with the right controller you can also have back breaks via re-gen. I'm talking about a motor like this: https://www.goldenmotor.ca/products/72-Volt-3KW-BLDC-Motor-Air-cooled.html

good luck

 

[markz]

Cyclone sells BLDC motors I saw a 10K and a 20K, could easily mount it above the crank, 20K was $850 with controller.

 

[Tony01]

Cool, so it looks like I have a few options.

Tig, the motor you linked to is rated at 3kw. Why is that motor OK to run in mid drive, but a 5kw rated motor is needed for running in the hub? Does it have something to do with being able to gear it correctly, like my gas motor?

Nice project you have linked in your sig BTW. that is some quality bodywork. Bet that took a lot of work!


Yea my old frame is so beat up, I would not mind fabbing up a new rear section to accommodate a hub motor. In fact, I have enough parts to almost build another bike. Just need small stuff like a front brake and a seat.


About the rear brake, I never said I don't need it, I just said I don't care much about it. Right now I have a 100mm drum in the rear but it's not hooked up. Rumme has decided to keep repeating the same crap, however I do like to run with two brakes, just it's not a priority. If I could have regen braking in the rear it would probably be enough. Right now most of my light braking is done with the engine compression. I ride fast 50+ daily, but I'm typically riding in the middle or left lane as its much safer than the right lane or bike lane. And I do daily drive this bike, so I am well aware of the limitations of my components, as well as having a good idea for the maintenance required.

While it's not hooked up, though, I won't be riding over the mountains.

I'm not here to argue with losers. Just trying to get some info. If anybody wants to know about heavy duty bicycle wheels, I'd love to help.

 

[dogman dan]

My gut reaction is if your gasser is that good, why go electric? Not for legality, that's for sure.

Or maybe for legal, but that means limiting power to whatever is legal where you are, which is cheap.

Bad ass electric, as you want is never cheap. You will either spend a lot on batteries, or spend it twice. 60 mph will take a strong battery, and 15 miles range at that kind of power level means a decent size of it too. All much heavier in the end, than your gas motor.

You can do a modest, still illegally fast e bike on the cheap. Generic hub motor, 72v 40 amps controller, and 10 ah of RC type batteries.

Motor and controller well under $500, batteries close to $500, and charger can be fairly cheap. 40 mph club e bike. Now its still pretty light, since 72v 10 ah of battery is not that huge, and heavy. It will do the 15 miles at 30 mph, with 40 mph when you need it.

 

[SlowCo]

It seems your looking to build something like this:
http://www.cyclone-tw.com/20kwbike.html

Or this:
http://www.cyclone-tw.com/18kwbike.html

 

[rumme]

My gut reaction is if your gasser is that good, why go electric? Not for legality, that's for sure.

Or maybe for legal, but that means limiting power to whatever is legal where you are, which is cheap.

Bad ass electric, as you want is never cheap. You will either spend a lot on batteries, or spend it twice. 60 mph will take a strong battery, and 15 miles range at that kind of power level means a decent size of it too. All much heavier in the end, than your gas motor.

You can do a modest, still illegally fast e bike on the cheap. Generic hub motor, 72v 40 amps controller, and 10 ah of RC type batteries.

Motor and controller well under $500, batteries close to $500, and charger can be fairly cheap. 40 mph club e bike. Now its still pretty light, since 72v 10 ah of battery is not that huge, and heavy. It will do the 15 miles at 30 mph, with 40 mph when you need it.

What he wants to build, is a bicycle with 26 inch rims, that will do 60 mph , and he doesn't care about back brakes...and he wants to to do all this as cheaply as possible and ride it mainly on ROADWAYS...I think this is very dangerous and certainly does not give the rest of us ebikers a good name. Laws are already being enacted in certain states, pertaining to ebikers.....IMHO, what he wants to build, only guarantess more and more states will have to create more laws concerning ebikes. NOT GOOD !

If anyone supports this type of recklessness, then you support the future laws that crackdown on the rest of us ebikers. I think you may agree with me.

 

[billvon]

stopping power must be proportional to speed.

Stopping power goes by the SQUARE of speed. In other words, you need 4x the brake to stop a 60mph bike vs a 30mph bike. (Remember, energy is 1/2 MV^2.)

 

[Tony01]

My gut reaction is if your gasser is that good, why go electric? Not for legality, that's for sure.

Or maybe for legal, but that means limiting power to whatever is legal where you are, which is cheap.

Bad ass electric, as you want is never cheap. You will either spend a lot on batteries, or spend it twice. 60 mph will take a strong battery, and 15 miles range at that kind of power level means a decent size of it too. All much heavier in the end, than your gas motor.

You can do a modest, still illegally fast e bike on the cheap. Generic hub motor, 72v 40 amps controller, and 10 ah of RC type batteries.

Motor and controller well under $500, batteries close to $500, and charger can be fairly cheap. 40 mph club e bike. Now its still pretty light, since 72v 10 ah of battery is not that huge, and heavy. It will do the 15 miles at 30 mph, with 40 mph when you need it.

Great info, thank you. I guess the pricing for speed goes up geometrically just as with gassers. 72v 10ah is about 60 cells, 50g each so... 3kg.. thats nothing.

The reasons for wanting an electric: 1. I want to see the country by train, 2. I want to experience greater performance, 3. I want to be much more stealthy on an illegal bike. here in CA the laws for ebikes and gassers are practically the same: 28mph and 30mph, respectively.

My gasser is great. I have about $2000 into it. The first one I built with a briggs 3.5hp only topped out at 47mph and was a lot cheaper.

First build- 3.5hp with 2-speed automatic transmission



Riding video - shifting and hill climb https://www.youtube.com/watch?v=4_hJXpjrddo

I really miss the light weight of this original bike, and the bicycle "feel" it had. It wasn't very fast but it was pretty good for what it was.

I want to build something like this:



On my old frame that looked like this without engine:

 

[MadRhino]

I agree. The QS205 H50v3, is what I recommend, easy to build for 70 Mph. Yet a 273 H40 is interesting when weight and big battery are not much of an issue. I would consider one if I had to carry a passenger often.

 

[speedmd]

My choice would be to do a mid drive on that frame. Tons of room right in front of the rear tire for a bunch of different motor choices, and design would be a logical progression of your previous gasser builds. It would be better balanced also, having the motor more central. The new QS mid drive motors look like they could do the speed if geared correctly. Check with them as they have some higher watt models with mated controllers that are impressive but not listed yet.

 

[wturber]

I think this is very dangerous and certainly does not give the rest of us ebikers a good name. Laws are already being enacted in certain states, pertaining to ebikers.....IMHO, what he wants to build, only guarantess more and more states will have to create more laws concerning ebikes. NOT GOOD !

If anyone supports this type of recklessness, then you support the future laws that crackdown on the rest of us ebikers. I think you may agree with me.

I agree that building and riding that bike in traffic is a bit reckless and ill advised. It is also illegal - probably in every state. So what he's doing doesn't really justify the creation of any new bike laws. It has already been covered.

Also, the laws being proposed in Arizona and other states - while a mixed bag - are in some ways, more liberating for some e-bikers.

 

[tigcross]

motor you linked to is rated at 3kw. Why is that motor OK to run in mid drive, but a 5kw rated motor is needed for running in the hub? Does it have something to do with being able to gear it correctly, like my gas motor?

Totally, a hub motor is direct drive (unless you go with a gear motor which you can't because you need more power) and then laced into what is essentially a giant lever working against it in the form of a rim. For this reason hub motors have to produce huge amounts of torque. An external motor can take advantage of gear reduction to create more torque with less power. That said, I really like the simplicity of hub motors for road machines, and I love having the extra space on the frame for batteries. Part of the reason I went with tiny 10" scooter wheels on the Electrom was to get more torque with less watts on a hub motor.
...And don't take my opinion on whether 3 KW is enough for your application, I tend to trial and error that sort of thing.

 

[MadRhino]

@rumme

Those who are giving ebikes a bad name, are riding stupid and careless; and perceived as a nuisance by other users of the street. It has nothing to do with speed and power. Then, no one can give YOU a bad name, but yourself. :wink:

 

[rumme]

@rumme

Those who are giving ebikes a bad name, are riding stupid and careless; and perceived as a nuisance by other users of the street. It has nothing to do with speed and power. Then, no one can give YOU a bad name, but yourself. :wink:

Yeah, you right . He doesn't have to worry about back brakes on a 60 mph bicycle riding on the roadways and since he wants to do this the CHEAPEST way possible, I'm sure he will register the ebike, get liability insurance on the ebike and build it with blinkers, headlights, tail lights , brake lights . . I apologize...I thought this sounded careless but was wrong . :wink:

 

[billvon]

Those who are giving ebikes a bad name, are riding stupid and careless; and perceived as a nuisance by other users of the street. It has nothing to do with speed and power.

Well, it does have _something_ to do with speed and power; you are going to be able to be a much more effective nuisance with a 50mph bike than one that can barely get to 20mph. (But yes, both bikes, when ridden by someone careless, can be a problem.)

 

[MadRhino]

Those nuisance who are riding fast bikes tend to be self destructive. So, on a slow bike, one can be a nuisance much longer.

 

[Raisedeyebrows]

I gotta hand it to anybody who can ride a rigid frame Schwinn cruiser at 50 mph, no thanks, give me full suspension, just looking at those things makes my lower back ache.

My motto-I'll ride anything with brakes...................I better add and good forks too, especially over 30 mph.

 

[The fingers]

I gotta hand it to anybody who can ride a rigid frame Schwinn cruiser at 50 mph, no thanks, give me full suspension, just looking at those things makes my lower back ache.
My motto-I'll ride anything with brakes...................I better add and good forks too, especially over 30 mph.

For me, 20 mph is crazy fast on an old beach cruiser. :wink:

 

[dogman dan]

I certainly never meant to criticize him for having a 60 mph bike, e bike, gasser, whatever. Or imply he can't ride. His survival so far sort of indicates he can RIDE! Others would be dead meat on that gasser, like they are on regular motorcycles. There is no indication he rides dangerously, to him or others.

But you need to look into amtracks rules for carrying a bike, particularly an e bike. I thought they sucked, you have to tote a crate around for it, and shit like that. Perhaps that changed? I don't know. Commuter trains can be different, but still not allow a bike unless its a folder, or allow bikes, but not motor bikes of any kind.

Again,, I can't stress this enough,, I would not change that gasser. Its magnificent. Keep it for when you want to go 55 mph. Then build another electric bike, on a similar budget to the gasser, that runs 72v 40 amps. 40 mph aint that bad, and the battery will be much cheaper. I may not have mentioned it, but battery cost, size, and weight goes up really fast when you run the e bike fast. So an affordable 72v 10 ah pack, which is about 700 watt hours, runs out fast if you pull 40 amps. 17 minutes and done. In the real world, full speed cruise on that power of bike will take closer to 30-35 amps, but still, done in 20 min. But if you cruise at 17 amps, around 25 mph, then it lasts 40 min of run time. Obviously you want to at least double that battery size later on, but its still not going to last as long as a gallon of gas, or refill in seconds, like the gas bike does.

This is why the fast electric bike is not cheap. Battery. Motors are relatively cheap, controllers too. But that dang battery costs you, unless you keep it running at closer to what's legal, allowing less size to satisfy your ride length needs.

NOTHING wrong with having it fast and powerful, and riding it legal speeds. This is what I do with my current street ride. Its 60v, and up to 40 amps. It can just hit 40 mph. The controller I generally limit to 25 amps, giving me about 30 mph top speed, which is the legal limit here in New Mexico. But I can call up 40 mph in just a few seconds, if I want it. This is the bike, which currently carries 60v 15 ah in one of the saddlebags.

The bike started as a cheap Schwinn, which I lengthened 9 inches, and added disk brakes. The hub motor is a powerful crytstalyte, capable of 3000w without any overheating issues. So I got better high speed handling by lengthening it, and more dependable (IMO) brakes. But 90% of the time I ride about 18 mph. Why? Because I want ride length more than speed most of the time. I have about 30-35 miles at slow speed, where I pedal. Only about half that if I rip it. The bike is quite capable of carrying double the battery, which would give me 60 miles range, but at the moment I only have 15 ah.



When I really want fast, then I hop on a gas scooter. Unfortunately, the garage fire that took most of my batteries and my best ebike, also took my scoot. But when I replace it, it will only cost about $2000 for a used one, that goes 90 mph easy. One bit of last advice, keep that e bike battery outside the house, or garage.

 

[MadRhino]

The extra cost of a fast ebike is not only in the battery. Not for a rider who is concerned about proper handling and safety of a powerful bike that he does ride everyday. Performance has a cost in components quality and building requirements. Otherwise, you might find out pretty soon that your 60 Mph bike is a good ride at 30.

 

[John in CR]

If you go hubbie forget the big wheels. None of these guys cruise at 50-60 for long distances on their ebikes. I've been doing it since 2008. Budget hubbies up to the task are found on used e-scooters with dead batteries, and you may get a working controller out of the deal too.

The other budget route is to get a car or truck alternator and run it as a motor. I haven't done it, but there are threads here on the forum about how to do it.

Once you get into those speeds aerodynamics is everything, especially since you're on a budget. That's because the battery is your most expensive component, and 50mph+ eats battery capacity quickly. In terms of the bike, think long, low, and sleek.

 

[billvon]

The extra cost of a fast ebike is not only in the battery. Not for a rider who is concerned about proper handling and safety of a powerful bike that he does ride everyday. Performance has a cost in components quality and building requirements. Otherwise, you might find out pretty soon that your 60 Mph bike is a good ride at 30.

Agreed. A lot of people make this mistake - take a cheap Wal-Mart MTB with rim brakes and put a 2KW motor on it. Hey, the bike isn't the important part for going fast, right? It's the motor.

But even if you get the motor/controller/battery playing together, at some point you are still on a bicycle going 55mph. And at those speeds a few broken spokes, or a suddenly out-of-true wheel after a bump, or a broken crank arm, or a panic stop becomes a MUCH bigger deal than the same events at 25mph.

 

[markz]

Nothing wrong with a Walmart bike with a powerful motor attached to it. Sure its a BSO (Bicycle Shaped Object) but if it gets you from point a to point then thats good.

The problem arises when you want to go fast, smack a simple pothole and your eating pavement.

The average person only needs to go 30-45kph, with very short runs of 50-55kph, which is like 15mph-30mph. Those who go faster on a bicycle not meant for that speed, I dont know what the rush is.

 

[Chalo]

A lot of people make this mistake - take a cheap Wal-Mart MTB with rim brakes and put a 2KW motor on it.

It's not the rim brakes that are a problem; it's the Walmart brakes. Rim brakes worked fine for 120+ mph Honda racing motorcycles and 150 mph land speed record motorpaced bicycles. The rim is just a great big brake rotor after all.

But the point remains that bicycles will not handle or stop appropriately at energy levels ten times or more greater than their design parameters anticipated.