48V vs 72V

[MadRhino]

...
Also i dont want to get hurt...

Nobody wants to get hurt, but that is a probability that a rider has to accept. Anything you ride will hurt you sooner or later: horses, motorcycles, bikes... even women :wink:
This fact has little to do with speed. It is part of the learning process, and the choices of rides that you make. Then, once you are not scared or nervous anymore, crashes are less frequent and less painful. 8)

 

[OCCOMBILL]

No, 72 volts is way too fast for an ebike in my opinion. You risk a lot by going that fast. 48V is the max and is far safer.

This reply makes no sense. Slower machines are far less safe. I have 130,000 miles or so on my 2014 touring motorcycle. For that, I chose the BMW K1600, which is basically in a class by itself, because of it's speed capabilities (160hp, 134lbs torque, Zero to 60 in 2.7- without shifting out of first gear, a top speed of 150mph, and a design that lets it lean far enough to carve up the twisties at speeds other tour bike couldn't dream of.)

Absolutely no one goes out and tests all those capabilities on the road on a regular bases, as that would almost certainly result in death. However, there are frequently situations where those capabilities can and eventually will save your bacon! In the same emergency situation lesser bikes are left with choosing brakes or steering left or right, the K1600 adds the ability to hit the gas a d remove yourself from the situation... right now. Say you're on the 405 keeping up with traffic, with imbecile tailgating you, another car about to wiz past you in the passing lane to your Left, and a second imbecile drifts into your lane while staring at their phone... what do you do? Well, if I'm on your average big twin, it is already near it's limitations, so all I can do is pray. On the K1600 by contrast, simply give it some gas, and you'll leave the imbeciles like they were standing still. Speed is a valuable safety feature added to your options.

My current fastest ebike only hits about 34mph... but it's a damn sight safer than my e-fat bike, which only does 24mph... because it can get me out of more danger. I ride around Long Beach mostly, and use the kamoot app to track bike performance. On either bike, my average speed is almost invariably 16-17mph. Would I be safer on a bike that could accelerate twice as fast and hit even 50mph? You can safely bet your ass I would be, because it could get me out of more trouble.

I damned near learned this lesson the hard way, when I got caught in a storm on a 250cc Honda Helix scooter. Great ride, and "capable of highway speeds." Well that capability is wonderful, right up until you find yourself in a situation where the only way out is forward, and that requires more powdr than you have. Fortunately, I survived getting rubbed by an idiot in a car, but then found I hadn't ridden the bike again for like a month. I immediately put it up for sale, and never road it again, because I believed my dad when he told me that if you ever get afraid of your bike, sell it or you're going to kill yourself.

I signed up just to post this reply, because your advice is dangerously bad, but looks popular with others who know no better. Not everyone building an e-bike is a fearless teenager who will push it's limits every time they get on it. But they sure will be grateful for more speed if they ride long enough to need it to get out of trouble.

In short, your ability, knowledge and practice is what dictates your safety level, most of the time, but shit happens... and a more capable machine can only add to that safety if you ride responsibly.

 

[amberwolf]

No, 72 volts is way too fast for an ebike in my opinion. You risk a lot by going that fast. 48V is the max and is far safer.

This reply makes no sense. Slower machines are far less safe.

Disregarding the entire "safety" discussion; the voltage of a system does not force it to be a faster system.

The system can easily be designed to run on as high a voltage as you wish and still operate only at a very slow speed, .

A low voltage system can also be a high speed system.


There can be disadvantages to designing either method that way, but there's nothing actually preventing it from being done.

In short, your ability, knowledge and practice is what dictates your safety level, most of the time, but shit happens... and a more capable machine can only add to that safety if you ride responsibly.

No argument with that.

 

[999zip999]

Welcome to endless sphere OC Mr Bill I like riding my 72 volt mountain bike that goes 44 mph. That is everything except for the weight of the battery and the weight of the motor . I'm now riding a backup 52 volt 35 amp controller 1500 watt yescom 235.00 kit shipped. I like its lighter and I can get it on the bus bike rack if need be yeah that's the bus that goes to your house the number one bus.
But 72 volt is more expensive on the controller the battery and the charger that are harder to find cheap that work. As there's a lot of junk out there.
You guys got a lot of good clubs in Long Beach.
Plus I like the bike trails without cars and keep off the # 1 especially in tourist town Laguna Beach.

 

[RTLSHIP]

can you overvolt the yescom kit?

 

[wturber]

In short, your ability, knowledge and practice is what dictates your safety level, most of the time, but shit happens... and a more capable machine can only add to that safety if you ride responsibly.

You are basing your rebuttal on the idea that the bicycle is ridden responsibly. But the OP expressed that the 50 kph top speed he has/had "isn't enough" and that he'd be happy he would be if the 72v system would let himi ride at around 65 kph. He wants to ride his ebike at motorcycle speeds, not the bicycle speeds you are riding your ebikes at. Given that context, the 72v is "too fast" or at least less safe in this rider's hands.

The original post is quite old. I wonder if the OP is still alive? ;^)

 

[E-HP]

can you overvolt the yescom kit?

If you’re running 48v then 52v is likely safe with the kit controller.

 

[E-HP]

He wants to ride his ebike at motorcycle speeds, not the bicycle speeds you are riding your ebikes at. Given that context, the 72v is "too fast" or at least less safe in this rider's hands.

The original post is quite old. I wonder if the OP is still alive? ;^)

Looks like he at least made it to June of last year, per the login stats.
There are more performance benefits of going to 72v than just speed. My wrist dictates how fast my bike goes, and how quickly it gets there. I’ve never seen the top speed, but I’ve gone fast enough (until the brain cells kicked in). I feel safe up to 20mph with a bike helmet and regular glasses, so that’s my cruising speed.
Past 45 or so, regular glasses don’t shield your eyes enough to ride safely even if the road is wide open. Your vision is blurred, and you’re toast if you crash. I can’t force myself to ride a bicycle wearing a full face helmet, so the brain tells the wrist, 20mph (but it only takes a couple of seconds to get there ).

 

[DaLanMan]

eww, I almost started off with "back in my day" but luckily dodged that bullet.

My first motor driven cycle was in my possession before there were laws about helmets. I still wore one but yeah...

In any case, if your glasses are not helping with wind, you are wearing the wrong glasses to ride.

I generally wear polarized glasses due to some issues with day blindness. Stupid northern european heritage resulted in my viking size and affinity for dimly lit rooms. So, I fell in love with Maui Jims sunnies, super light, amazing optical clarity, requires selling your first born and taking on a national debt level investment (ok, it is like 150, but that does not sound cool).

I wear em all the time, but the minute I am around things that go zoom without a ceiling, I switch out to
These

On my face they give very good coverage and I have been on a bike with a skull cap and got it up over 100 for a brief minute (just testing a buddies new ride out) and they did an admirable job of keeping my eyes from going all blurry... Did not keep the permagrin off my face. I miss suicycles...

Granted the reality that the tumour on my spine is slowly stealing all the sensation in my left leg means that yeah, I am building a trike and hoping I can get one more summer in with my son before even that is not enough to make it possible to ride.

 

[Teeman]

I Have 5 72 volt 60 amp 5000 watt ebikes I put about 5000 miles a year on them .I never had any road problems, The funny part is I mostly ride at 20 to 25 mph. The best part is when need the speed to get off of a real dangerous road I am able to get off IT in A hurry. This is the reason I have them. I have the best tires and brakes money can buy. I obey all rules of the road ,and the respect the power. You can easy get in to trouble with that kind of power. If you go to 72 volt Please be careful.

 

[E-HP]

eww, I almost started off with "back in my day" but luckily dodged that bullet.

My first motor driven cycle was in my possession before there were laws about helmets. I still wore one but yeah...

In any case, if your glasses are not helping with wind, you are wearing the wrong glasses to ride.

Well I'm not going to get anything special for riding a bicycle, but I'd rather ride bicycle speeds than get glasses to ride faster. But ya, before helmet laws, I'd do it all the time, with better glasses of course; as long as there aren't bugs out and you remember to wash the road grime off your face afterwards, it's fine. I recall riding up to Reno once and I was wondering why I was getting so many stares. Then a guy a the gas station mentioned helmet law, and it occurred to me that I was in Nevada.
My helmets save my life in 3 crashes, 2 going fast and one being T-boned by teenagers running a red light. I'm pretty sure during one of those occasions, I may have been tempted to ride without a helmet, if there wasn't a law,

 

[gromike]

I always rode with a helmet, but when I was young and dumb I rode without I eye protection. I remember one rather long ride on a 250cc 2-stroke Suzuki. I was riding in California's southern Central Valley during cotton harvest. That was painful. Actually, the whole trip was painful, but I was eighteen, so it just hurt and didn't cripple.

 

[DaLanMan]

I got hard core convinced about safety gear when I was like 18...

I had been in the army for 2 years, and figured I was the toughest SOB on the planet.. Had a full month break from playing soldier, came back to Cali for the first time in a couple years, got invited to go to Lake Berryessa for a day of stupidity on the water.

Decided I did not want to go through all the hassle of getting my car back on-line (let em set for 2 years, they get uppity) Bought a bike and figured I would have it shipped to Benning (my first full career duty station) I was all set, bought a brain bucket (minimal helmet for those that have never heard the term) a pair of RayBan Wayfarer 2's and off I went, small bag of gear on the back, leather jacket, shorts and riding boots.

First issue, some GIANORMOUS bug hits the right lens, have to turn around, go to gas station and spend a good 20 minutes cleaning the glass so I could see (still have the glasses, there is still a bit of what I assume is chiton stuck in the glass, or coating or whatever it is) hit the road, guy in a convertible vette is behind me and trying to keep up. This only becomes important when I rip a corner, come up to balance and WAMMO All I see is feathers and blood.

I took a bird strike to the chest at like 90.. .I could not see, I could not breathe, Gear down hit brakes try to remember how far I have to the next turn. Luckily I get stopped a good 3m before the edge. Guy runs up from his vet asking if I was ok.

Took the rest of the trip slowly, have not ridden without body armour and a full helmet since then. I have been on 2 wheels since I got a Briggs and Stratton powered bike when I first came to the US (I was 7) you can not plan well enough to be prepared for anything, but minimal protection decisions are important.

I have been called all kinds of things because of my basic precautions being higher than most. I have been shot, hit by a bus, hit by baseball bats, thrown rocks, thrown bottles and even yup, blown up and rag-dolled across the desert. I am not a "tough guy" I am just well worn in. It may mean I am weak that I wear armour... But I ain't getting killed by a bloody Pidgeon, that would be plane embarrassing.

I don't want to show up at the pearly gates, knowing I am gonna be refused, and have myself laughed out of the place because I was taken down by an assault pheasant.

 

[wturber]

I don't want to show up at the pearly gates, knowing I am gonna be refused, and have myself laughed out of the place because I was taken down by an assault pheasant.

Human beans are generally poor at risk assessment. The typical motorcyclist is no exception. The motorcycle fatality rate is about 25 times higher than that for cars when compared by miles travelled and 6 times when compared by registered vehicles. But given the very low rate for cars, it is a difference that is not easily observed through experience.

I did the math recently and as I recall, the odds of dying in a car accident in any year is about 1 in 10,000 on average. Even at a 25x higher rate that's still a 1 in 400 chance - assuming a similar amount of motorcycle miles. But the mileage is lower, so the real rate is probably something like 1 in 1000. Observationally, that is experiences as something almost invisible.

But expose yourself to this risk for 50 years and the car odds go up to 1 in 200 and the motorcycle up to 1 in 20. Those numbers should encourage a person to take steps to go to at least a moderate amount of trouble to tip the odds more in their favor. But how many people sit down and think it through. Probably very few young men. Your early lesson with the bird strike probably served you well. Making mistakes is understandable. Not learning from them OTOH ...