Ebike Weight....

[Newagebike]

I have done a lot of research on ebike weight expecially the steel/aluminum/carbon fiber heavy-duty enduro/stealth type frames that are made to hold the battery/controller and be stronger for the more powerful ebike build category.

These frames range anywhere from 23-12 or so pound range but the cost per pound range is redicules..meaning a 22lbs steel frame can cost around $450 delivered and on the lighter side of 12 lbs you will pay close to $1000 and up. These are rough figures.

So to the debate... what really is the huge benifit of 10 lbs weight savings in an ebike build in the Powerful ebike category made of the enduro/stealth frames?

Sent from my SM-N900T using Tapatalk

 

[MadRhino]

Saving weight has a cost, and the lighter it is, the higher the cost of making it lighter.

If some are willing to pay the cost of saving weight, it is because the weight saved translates in effective HP at the wheel.

Once you built the maximum power that can be achieved with your motor, you still can improve performance by saving weight. The performance gain of saving weight is important in acceleration and braking especially, while improved aerodynamics is the most important factor in top speed gain.

 

[motomech]

For the way I use my Ebike, weight is the least important specification to me.
I don't pick-up and carry my bike.
I am fine w/ staying at speeds below 25 MPH and am not currently pushing the limits of my motor(s).
Comfort, safety, range and reliability all come before weight and as yet, the overall weight of my bike does not impact those items much.
With my other ebike, which is used as a "assist" bike, weight is more important, but still not my main "thing". The PAS system kind of adjusts to the overall weight and makes the pedaling experience feel the same. All good, as long as the batteries don't die.

 

[st35326]

I can tell you that with identical Stealth Bombers me at 200 pounds vs. my buddy who is 230 pounds, the lighter rider seems to simply get to 50mph faster. In my case it was about 5 bike lengths faster. We even switched bikes and got the same results.

 

[MadRhino]

...All good, as long as the batteries don't die.

Weight also has a direct relation with range, for someone who values efficiency more than performance. Of course, those who are after efficiency are less likely to spend a lot of money and time building lightweight. Nevertheless, when it can be done at little cost with simple care about building choices, it is an advantage to be considered. To reduce weight and wind resistance together, can extend range more than most would believe.

 

[Recumbent Bicycle Source]

I rode the original Chrysler Ebike about 15 years ago. Near 80lbs if I remember correctly Designed by Chrysler. Total Dog. Handled poorlly. Old battery tech. Old motor tech. But fun at the time.

I now have 3 bikes... electric hub motors. All about 60lbs. That's a nice target weight in my opinion for hub motor/battery full gear combo.

Lighter matters on an ebike, but not as much as one might think. Design, Tires, etc really matter. The weight does matter if you do a lot of climbing (You eat up amps and stress weaker motors and create a lot more heat). And where is really matters is if your battery dies and you have to pedal home.

I have no issue with prices of a frame being $450 if it's well designed. In fact to me (We all have different budgets) that's a bargain. A good bicycle starts around $1,500 if you want good components and a fun riding experience with no motor. I've paid several hundred for a single wheel on my pedal only bikes. So it's all perspective.

You can score some nice diamond frame and comfort bike frames by stripping down Craigslist Bikes. To me the Townie is a nice frame for ebikes.

Anyways find something you like the feel of riding... then convert it. Don't worry so much about weight. Buy quality, invest in a quality Lithium battery and have fun.

 

[Newagebike]

The thing that gets me is 10 lbs can be saved in so many ways and I do not think 10 lbs will make any noticeable difference on ebikes in this category which in turn says to me to not care about the 10 lbs.

Just think most people can lose 10 pounds with out really trying and it will save them weight and money.

Sent from my SM-N900T using Tapatalk

 

[cycleops612]

It bears saying that its relevance is proportional to rider weight. my bike is ~25kg & i am 75kg. If only cars were similar proportionally?

~Philosophically for me, if i cant heft it, its not really a bicycle anymore.

Here in sydney Oz, the metro trains are a wonderful range extender. Most, but not all, stations have lifts/ramps, so hefting up stairs are a reality for this, and other situations.

Too heavy/awkward for a car bike rack is a downside. Not all have a truck available.

My plan B, is to single handedly load my E-MTB into a taxi sedan back seat, to get home if all else fails

 

[MadRhino]

The thing that gets me is 10 lbs can be saved in so many ways and I do not think 10 lbs will make any noticeable difference on ebikes in this category which in turn says to me to not care about the 10 lbs.

Just think most people can lose 10 pounds with out really trying and it will save them weight and money.

Sent from my SM-N900T using Tapatalk

Of course, the lighter the bike, the more noticeable 10 lbs will be. Saving 10 lbs off a Harley Chopper is not noticeable. Saving 10 lbs off a MX 125 is noticeable, and saving 10 lbs off a 80lbs bike is very noticeable.

Then, most who are building without weight in mind, end up with much more than 10 lbs extra. Rider's weight is not relevant, for the same rider on a lighter bike will notice performance improvement. Yet, the weight saved off the rider does count as much as off the bike (except for wheels that are making more difference per lbs than anywhere else). So yes, if you can workout some off your body weight, you will notice a performance improvement. It is not for aesthetics that we hire a 140 lbs jockey to race a horse. :wink:

 

[LockH]

Wiki: "kinetic energy":

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes.

In "ebike terms", esp. in urban "stop and go" traffic, translates as less range per charge and probably w/higher outputs from battery shorter life before recycling/replacement. Also, up hills = "bad". Subtract from negs, any/all regen as "good".

 

[dogman dan]

So much depends on what the use will be. Some of my heaviest bikes ride beautifully, though the 100 pound weigh of them is noticed by the motor, and you see that in higher watt hours per mile numbers. But those heavy bikes are cargo haulers, built specifically to haul cargo and tow trailers. They handle fine though, descending a steep mountain hill.

But would I want a 100 pound e bike for trail riding? Hell no! For off road, or other performance type riding of course shaving 10 pounds off will help a ton. Shave another 10 off your body will help twice. The lower body weight will help efficiency, and time to full speed more than handling though.

For this reason, I carry a small battery for short fun off road rides, rather than a huge one for longer trips off road. I'd rather swing back for a fresh battery than carry that extra 8 pounds the whole ride for sure.

Now, is adding about 3k to the price worth it for the carbon bike? Yes,, if its in your fun budget. No, if you could use that cash much better to pay off your house sooner. Fun budget is relative,, to your stage in life, current income, and debt load. At one point my fun budget was $300 a week. We were having big time fun in our prime years. But now the fun budget is more like $20 a week.

 

[Raged]

As others have said, it's all about use. My CX 29er dropbar bike is about 41lbs because I sometimes need to lift it over stuff like fences and logs. It will still do 32mph and have a good range with a bit of peddling. If it was just a commuter with flat roads then it doesnt really matter as much as long as you have good brakes and fat tires for grip.

 

[Robocog]

Almost as important is WHERE you carry your weight.

My bike is 46lbs. It is an aluminum frame. HEAVY duty. And yet, only one or two lbs from the very light. Its suspension is DESIGNED to ride like a 100lb bike.

And yet, all the weight is central. unSprung weight is STOCK.
The flickability of the bike is key. I intend to add clip pedals, and be able to bunny hop up curbs.

I will invest another say eight hundred bucks, to remove maybe four lbs. 42 lbs will feel almost pure mountainbike. It will ride like a caddy.

Have switchable maybe 100 to 130mm rear, 100 to 160 front. It will handle the stop and go MUCH better. I will be able to balance it whilst waiting for the light to change.

It will go 35mph, which is PLENTY fast for me.

Now I need to design my inflatable streamlining jacket. With MIPS type cooling.

 

[John in CR]

.. what really is the huge benifit of 10 lbs weight savings in an ebike build in the Powerful ebike category made of the enduro/stealth frames?...

None. Anyone who disagrees will have to explain why one of the heaviest people on the forum who weighs far more than 5kg more than the average ESer still enjoys far higher ebike performance than all but a very select handful of members.

 

[Chalo]

A heavy bike is unpleasant to ride and to handle when not being ridden. A light bike is not only a pleasure to live with, but it does more work with less energy, less material, less burden.

If weight doesn't matter, you can get a motorbike that packs 100,000 rear wheel watts or more and weighs around 500 pounds. That makes a porky little "high powered" e-bike look like a toy. But that's not the point, is it?

If you want efficient, quiet, safe transportation, then weight does matter. The whole category of motorcycle-like e-bikes is stupid, because they're terrible bicycles and lame motorcycles at the same time. If you want a motorcycle, get a motorcycle. If you want an electric bicycle, let it be a bicycle. We've had a century and a half to work out what makes a good bicycle, and low weight tops the list of criteria.

 

[MadRhino]

....We've had a century and a half to work out what makes a good bicycle, and low weight tops the list of criteria.

Yep, if you want a bicycle, forget about motor and batteries.

As soon as it has a motor, your bicycle becomes a motor cycle. Then you can define your requirements and optimise your motor bike for them. Weight is just as important, but you accepted it will never be a bicycle anymore. It can be small, it can be big, as you need. Then, don't go believing you can't build a good ultra light weight motorcycle, and one that handles as fine and safe as the best.

 

[kingjamez]

....We've had a century and a half to work out what makes a good bicycle, and low weight tops the list of criteria.

Yep, if you want a bicycle, forget about motor and batteries.

As soon as it has a motor, your bicycle becomes a motor cycle. Then you can define your requirements and optimise your motor bike for them. Weight is just as important, but you accepted it will never be a bicycle anymore. It can be small, it can be big, as you need. Then, don't go believing you can't build a good ultra light weight motorcycle, and one that handles as fine and safe as the best.

DING DING DING. I sometimes wonder why Chalo is even here. He clearly hates electric bicycles beyond what his "ideal" bike is. Forums are wonderful because of their diversity.

Newagebike:
In your other threads, it seems as if you are after an on-road, commuter type, light electric motorcycle that happens to have pedals. If that is your use case, then weight doesn't matter as much compared to other ebikes that are used for off-road trail riding applications. Weight matters, no matter what, it just matters more in some applications than others.

I'll speak to what I "believe" is your case... If you are on-road, a "heavy" frame like an EEB is ultralight compared to a normal motorcycle. With decent hydraulic brakes you can stop faster than almost any car in front of you. Add in strong regen and you can stop faster than any car period.

Where does weight play in? For this use case, it's gravy on top. Lowering weight will enhance everything, but obviously, at cost. It'll accelerate faster, handle better, stop faster. However, not worrying about weight may completely satisfy you.

As an example. Let's compare the carbon ebike frame on eBay right now to an EEB frame. The EEB frame weighs roughly twice as much; lets say it adds 12 pounds. In the case of the QS205, the laced motor weighs in at 30+pounds, the battery is variable but at a minimum is going to be at least 20 pounds. Seat, shocks, tires, controller, etc, at least another 10 pounds. So you'll have 70 lbs of "non-frame" weight just for the bike. Add in your body weight, I don't know it, but let's use me as an extreme example. I weigh 130 pounds. Lighter rider weight means more impact by reducing overall weight. So, 70+130=190 total pounds of non-frame weight. Now let's consider the frame. Going carbon over steel will make at a maximum a 5% difference in overall weight. While the lighter frame will be better, the overall impact on performance and efficiency will be minimal. Heavier riders will make the differential even smaller.

-Jim

 

[Alan B]

Weight is related to power and stability. A 100 pound ebike feels very light compared to a 500 pound emotorcycle. Same for a 60 pounds ebike compared to a 100 pounder, same for a 30 pounder compared to a 60. But if you put the power of a 500 pound emotorcycle onto a 30 pound ebike Luke would love it, but most riders would quickly self destruct.

Balance matters. Weight distributed properly feels lighter than poorly distributed setups.

Low weight costs. What can you afford? How light do you need?

Weight matters most when you need to lift and/or carry the ebike. I have ebikes from under 40 pounds to over 100 pounds. Commuting every day on a 100 plus pound ebike was near perfect. As long as there were no problems. Flat tire, charger didn't complete the night before, controller FETs failed were incidents that made for memorable (very short or extra long) rides. However the very things that made the ebike heavy made it reliable (moped tires rarely got flats, plenty of battery range, big torque and regen saving brakes, etc).

Lighter ebikes tend to have more reliability problems. Flat tires are more common. Batteries lose capacity quicker and don't have much reserve range when they are smaller. A heavy ebike with lots of gears can actually be pedaled long distances, it is like riding a touring bike with panniers loaded with camping gear.

A 30 pound ebike is easy to pedal long distances, providing the chain, gearing and tires are OK. If the tiny geared hubmotor jams up due to broken gears, or the mid drive breaks the chain or the chain breaks the spokes then the bike is not going to pedal far. How prepared are you to fix problems on the road when travelling light?

It really depends on your route, your alternates, your backup support. If you have to take your ebike on taxi or bus if it fails, you don't want it heavy. If you can call wife-star or your many friends to bring a pickup truck or SUV or vehicle with bike rack when you need help then a heavy bike won't be a big difficulty, unless it breaks too often. How unreliable is your ebike going to be?

Reliability is key. If your setup is reliable then you won't need rescue very often.

If you need to carry your bike up stairs, in elevators, on public transportation then light is better (and perhaps folding is required). How light can you afford? Cost becomes a limiting factor.

Simple, reliable and strong DD hubmotors are heavy, so going light drives the solution toward mid drives and small hubmotors. Small hubmotors need to be geared to have much torque, and the gears and clutches drive reliability down. Mid drives also require significantly more maintenance than DD hubmotors. So light weight drives the solution away from the low cost high reliability that DD hubmotors offer. That's why so many use a DD hubmotor in a low cost ebike and it comes out somewhat heavy. For high reliability, low cost and reasonable performance (ability to climb well and reach good speeds) the heavier DD systems provide the best overall compromise. Most buyers are on a budget.

If you want to go light, then make everything lighter, it is better for cost and balance. No sense in spending for a carbon frame and then use a heavy DD hubmotor.

Another thing about really light ebikes - they tend to be noisier due to the use of small high RPM motors and geartrains, which are lighter. Friction drives, Tangent mid drives, etc are noisy. How much noise do you want? DD hubmotors with sinewave controllers are the quietest systems. Geared motors and mid drives make some noise. The lighter they are the more noise they tend to make.

One thing about ebikes - there are a tremendous number of choices. Plus they are fairly small so you can have a few.

 

[Newagebike]

Some great reading here. I do stand with what I said, 10 pounds is not worth the 1000's it it will cost you to save it when buying your frame in this ebike enduro frame build category.

The only thing that will make a build like this to be called an ebike is the peddles but then why put them on? Because they aid the motor,battery when starting from a stop and they will be there if you need to pedal home which is a cool benifit.

Moped comes to mind.

Sent from my SM-N900T using Tapatalk

 

[Chalo]

As soon as it has a motor, your bicycle becomes a motor cycle. Then you can define your requirements and optimise your motor bike for them. Weight is just as important, but you accepted it will never be a bicycle anymore.

.

Right-- so be honest and get rid of the pedals you don't/can't use, get the thing registered and insured, and for cripes' sake stay off of bicycle & ped facilities. It's not a bicycle.

 

[Robocog]

We are also to be GOOd stewards. The idiots with drones, have brought the heat onto ALL RCers. Same with the hot rodders. Go ahead and REQUIRE more responsible folks to REGULATE you.

I have always followed the rule, that I don't want Anyone telling me squat. SO, you MUST be your own limit. Opening up only when safe. I have an R1 with 165hp at the wheels. It is 395 sopping wet. I put a larger rear sprocket on. It is the fastest bike around. It will do 180 still with the lower gearing.

BUT, when I am in the HOOD, I use GOOD judgement. I know that there are plenty of folks wanting us banned or dead etc. So, I don't scare folks.

I don't flip them the bird if I scare them unintentionally. I let folks in. Most of the time, I don't even use signals, as they don't know I am there. I am a ghost. BUT, a self assured one that moves with authority. AND intention that is clear.

We need responsible folks to be ambassadors. NO, NOT like Kislyiak. WE will all pay if the flouters are too brash.

Oh, and PS, kif you think you can stop faster than cars, YOU WILL BE HURT soon. The center of gravity is high, the contact patch is subject to road debris. You have squat stopping power when leaned.

 

[Newagebike]

@Chalo,

Did you see my post? The pedals help in 2 great ways. Pedal from start to help motor/battery, the pedals are there in case you need to pedal home.

Maybe not ebike but rather moped which is kinda like an ebike

Sent from my SM-N900T using Tapatalk

 

[Chalo]

The suitcase/motocross type e-bikes I've worked on (Phasor, Flux) are too fat to pedal without rubbing on the battery box. In that case, pushing the thing home is probably more practical than trying to pedal them. To pedal them, you have to set the seat way too low and then poke your knees out like riding a horse. The fact that they even have pedals is kind of a sad farce.

They've weighed three times as much as my pedal street bikes and six times as much as normal road bikes. But because of the motorcycle tires and direct drive hubs, they have way more than six times as much rolling drag as either one.

 

[slacker]

chalo, e-bike forum ?

 

[Newagebike]

@Chalo,

I hear you but comfort of pedaling can be addressed with adjustable seat post, (Reverb Seat Post) and also the right gearing. As far as legs rubbing that has to do with people's anatomy I have seen video of people pedaling all the different enduro frames and they are not rubbing their knees.

Sent from my SM-N900T using Tapatalk