Make sure you make the search legal first with "ebike 750W frame failure". Good luck.
How To Judge Quality
- Thread starter flugelboneman
- Start date
Sure they can fail. But not because of a 750W hub motor. All the bikes in your video are MTB regular bikes putting stress on the frame by how they are ridden, not because of a 750W hub motor.
erider_61
Well-Known Member
From what I can see the problems that occur with DIY mid motor installs seems to be from incorrectly mounting the BB hardware pictured below. The grooves are intended to dig into the BB so the motor does not move under torque. Other than this I can find no other issues related to frame failure of a DIY mid motor install. This makes sense as I hardly think any company is going to bring a product to market that will fail after 100 miles as @AZOldTech stated. These mid drives were surely tested for many miles before going retail.
Not really. Hubs put more stress around the drop-outs. Frame quality is important, thicker/heavier tubes, steel would work better than aluminum. Not any fork is a good candidate. Torque arm is mandatory for all but the smallest hubs, though it doesn't always resolve the issue.
I am not convinced that mid drive is easier for DIY. With a hub, the most tedious and most critical job is lacing motor into the wheel, but many times DIY just buy a wheel with motor laced in. Attaching controller might take some thinking, though not much labor. Remember, not all the hubs are created equal - some have controllers built-in.
Can't say about mids being inherently better quality than hubs. Do Bafang hubs fail sooner than Bafang mid BBS, is there any reliable statistics?
Commercially available quality emtb are significantly heavier than memtb - at least 4 kg more than you'd expect from just the motor / battery. ( I'm using a giant trance as the easiest comparison ). Mostvof the bolt on bits like gearsets etc are similar, so it's fair to assume that extra weight is in the frame and wheels?
I can feel my norco memtb flexing under neath me as I ride, the giant emtb feels rock solid.
So, either the engineers at giant know less than the average home converter, or justvperhaps it's a good idea to use a solid frame when carrying extra weight at extra speed with extra force?
I can feel my norco memtb flexing under neath me as I ride, the giant emtb feels rock solid.
So, either the engineers at giant know less than the average home converter, or justvperhaps it's a good idea to use a solid frame when carrying extra weight at extra speed with extra force?
I have built nearly a dozen rear hub bikes for friends and family over the past 4-5 years, with as crappy frames as you can possibly imagine. If a bike frame can carry a 200 lb person, then that frame will outlive a legal(750w) rear hub weight add-on (and I'm not talking doing crazy stunts on a mtn bike that can fail any bike frame). On the other hand mid drive motors are not so easy to do by comparison without re-engineering the motor for the drivetrain specifically with mounts, seat/chain stays, BB area of the frame, etc. if you want it to last. BTW every one my rear hub builds still going strong. Can't say the same with the diy mid drive that I tried.
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Makes one wonder why so many hub bikes cost more than $1,600-1,700 (in fact, most brands, other than a few makers/importers like Volt or RAD). Easy to build, less critical frame than with mid-drive, inexpensive motors.
Makes one wonder what the post #1 was about, too. Comparing department store bikes to elite bikes, - can't say I understand these terms, in particular context of ebikes. Cheap hub Volt should not be compared to more expensive mid-drives, because they are different drives, first of all. Hub bikes are cheaper because they are simpler. Hub "should" always be cheaper, given the same brand motor and same level of components, but it's difficult to compare properly, because very few motor brands come in both hub and mid variety (incidentally, those are cheaper brands).
It would make more sense comparing "quality" within the same category, i.e. hub to hub, mid to mid, fat to fat.
Makes one wonder what the post #1 was about, too. Comparing department store bikes to elite bikes, - can't say I understand these terms, in particular context of ebikes. Cheap hub Volt should not be compared to more expensive mid-drives, because they are different drives, first of all. Hub bikes are cheaper because they are simpler. Hub "should" always be cheaper, given the same brand motor and same level of components, but it's difficult to compare properly, because very few motor brands come in both hub and mid variety (incidentally, those are cheaper brands).
It would make more sense comparing "quality" within the same category, i.e. hub to hub, mid to mid, fat to fat.
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AHicks
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When you first step into the potential of becoming an e-bike owner, there's a LOT of information to absorb. Many (most?) are literally overwhelmed by it all (including myself)! It's not until after realizing the existence of direct drive, geared hubs, and mid drive bikes that it might occur to you that they ARE so different! From there I think, things start coming into focus a little better. Still a lot of information to absorb/understand prior to making a good call when it comes to which type might perform better for YOU personally.
At that point, it should start becoming more clear you really can't compare the 3 types without adding in the factors that make the drives so different. Kinda like motorcycles maybe. If you started with zero understanding, it's going to take you a bit to figure out a road/touring bike is not going to do as well in an off road environment as a dirt bike might. Very different machines for a very different environment.
Clearly, one type cannot be determined "best" of the 3. When you have a good handle on what the differences are, then you at least have a good shot at which might be "best" for you. It's not until then that you can start considering factors like quality. My thoughts anyway, FWIW. -Al
At that point, it should start becoming more clear you really can't compare the 3 types without adding in the factors that make the drives so different. Kinda like motorcycles maybe. If you started with zero understanding, it's going to take you a bit to figure out a road/touring bike is not going to do as well in an off road environment as a dirt bike might. Very different machines for a very different environment.
Clearly, one type cannot be determined "best" of the 3. When you have a good handle on what the differences are, then you at least have a good shot at which might be "best" for you. It's not until then that you can start considering factors like quality. My thoughts anyway, FWIW. -Al
ebikemom
Well-Known Member
My Pedego dealer told me that a hub motor puts a lot of stress on the frame.
When I had my bike at a big bike store's service dept. the tech said that part of my bike that was one piece should be in more parts, so things could be replaced.
I asked about it at the Pedego store, and that's when he told me about the issues with hub drives and frame strength. He said that Pedego learned by converting conventional bikes to ebikes which parts of the frame were at risk from stress caused by the motor. He said that the criticism of the bike tech was related to his not understanding how much strength is needed around the rear wheel frame area and that on that part of the bike, my Pedego is made in one piece instead of having more parts, for the purpose of strength.
When I had my bike at a big bike store's service dept. the tech said that part of my bike that was one piece should be in more parts, so things could be replaced.
I asked about it at the Pedego store, and that's when he told me about the issues with hub drives and frame strength. He said that Pedego learned by converting conventional bikes to ebikes which parts of the frame were at risk from stress caused by the motor. He said that the criticism of the bike tech was related to his not understanding how much strength is needed around the rear wheel frame area and that on that part of the bike, my Pedego is made in one piece instead of having more parts, for the purpose of strength.
What do you expect them to say? With a dealer network, the kind of margins they need to make, and paying William Shatner as their spokesperson, all that needs lots of customer money that only marketing BS could remedy. I think that is the 2nd oldest profession in the world. Marketing BS. Apple perfected it and they became the most valuable company in the world. What's really funny is looking at their ebikes they don't even look that over built. I mean Rad Power bikes look more overbuilt than those and they are significantly less.
If you decide to put a 300lb person or 350lb person on a bike, of course you will need a frame to support that. But as I said any frame that supports a 200lb person will support him and the extra pounds of the diy rear hub conversion. I'm sure the pedegos support heavier people than 200lbs. But the radpower which to me looks even more overbuilt than the pedegos will support even heavier people than what they say. But again this is apples and oranges. The fact remains that it is easy to diy a rear hub bike that will last given the 200lb rider limit. Not so easy for a mid drive bike.Although there may be some marketing BS, to be fair though, ebike frames do look much thicker than non-ebikes.
When I walked into the Pedego store, I could tell right off the bat that those bikes' frames are much more heavy duty and thicker (just like any other ebikes).
Did all the ebike companies unnecessarily made thick and heavy duty frame just for the sake of marketing BS so that they could tell their customers how strong their frames are? I don't think so..
Bicycle companies spend a lot of time and money testing their frames. Those testing equipment aren't cheap. And takes a lot of time.
Because those DIY ebikes you built with cheap frames, do you know exactly how much force it can sustain?
They may be holding up fine right now (just like other DIY bikes) but some people are willing to pay for more sturdier frames.
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6zfshdb
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With the wheels, motor and battery removed, the frame of my Pedego Interceptor weighs 2 1/2 times that of my Trek Shift 4 MTB. Visually, they appear to have the same diameter frame members.
There are standard, single, double and triple butted tubes of aluminum. All with the same outside diameter. Triple butted the lightest, standard the heaviest. A radrover ($1499) weighs 68lb (wheels, motor and 48V 14Ah battery on the bike) with rated 275lb capacity (even though I heard 350lb people ride it without any problems and I find that true as the Radpower bikes are quite overbuilt and they show it with their net weight). Radcity ($1499) is 63lb with same battery and 275lb as well. What's your Pedego weigh with what rated capacity, motor, battery?
https://bike-advisor.com/bicycle-guides/aluminum-frames-6061-vs-7005-which-is-the-best.html
So you can have a Radrover/RadCity at 68lb/63lb for a rated 275lb rider.... or a fulll alloy Orbea Gain ebike ($2999) at 28.7lb (13kg), or LESS than half the weight of other rear hub ebikes (the Orbea Gain is also a rear hub ebike using the Ebikemototion X35 hub motor)...
https://www.orbea.com/us-en/ebikes/road/gain-road/cat/gain-d40-usa-19
https://www.ebikemotion.com/web/x35-light-smart-ebike-system/
So IMO there is no reason why Pedego or RadPower can't built a RadRover or a RadCity with half the weight other than price and custom manufacturing ability. And half the weight means a smaller hub motor and battery to achieve the same speed and range. Light ebikes are the future of ebikes. Orbea is just one. More will follow and prices will come down as more and more people have had it having to lift a 60-70lb ebike. The benefits of lighter ebikes are many like being able to carry the darn thing up the stairs, faster stopping power and being able to ride it a hell of a lot easier as a light regular bike if the battery is depleted, so no more range anxiety.
The Orbea Gain Is the Future of E-Bikes
https://www.outsideonline.com/2335946/orbea-gain-e-bike
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In the conventional bike world, light has limits - either financial or functional. Reasonably priced conventional mountain bikes stopped at their current weight about 10 years ago and the only way to get lighter was fragile materials like carbon fibre.
So the only ways to make e bikes lighter are motor, battery, or fragile frame / parts?
I have no nterest in being the rider who discovers the latest emtb frame is too fragile. I've already discover the down side of fragile front sprockets, lighter chains, lighter tyres.....
Lighter battery means range anxiety ( or better software to manage that) - I really like the dual battery options but how many of us would want to manage 2/3 batteries or worse still discover we had miscalculated our weight / range ratio on the day?
So lighter motor technology sounds great - so we have about a 3 kg window for improvement but realistically that's closer to 2 kg. Ride more and lose that 2 kg, it'll be a lot easier
Orbea is an 88 year old bike company with a lifetime frame warranty on their bikes and a history that proves they do know how to design fast comfortable and strong bikes. So a heavy behemoth ebike weight does not necessarily mean a stronger long lasting bike. It's engineering and manufacturing expertise that goes a long way in making high quality bikes. So I would put my faith on a nearly 90yo company that has the history, engineering, manufacturing expertise and the warranty to back it up. In fact I have. One of my regular road bikes that I used to race with is an Orbea Orca and it was awesome! I'm currently all stocked up with ebikes but my next purchase will be an Orbea Gain for sure.
BTW, thinking out loud, I don't know how many of the last 5-6 year ebike companies have even a R&D engineering department let alone manufacturing capabilities in house. I think most of them go to china and pick and choose whatever the chinese have available, pick some options and are mass produced fast and on the cheap. After all it is much faster and cheaper to use standard aluminum tubes instead of hydroforming them to single/double/triple butted tubes which makes a tube lighter as well as stronger. And the more times a tube is butted the more expensive, lighter and stronger it gets, if you know what you are doing. Ultimately cost and major expertise is required for the manufacturing process to keep all the gains from the grain compaction in hydroforming.
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I understood you got 2 different opinions from 2 different people - one saying that your bike needs a stronger frame made of more pieces, and another one saying that your Pedego "been there, done that", and your frame is good enough as it is?
The truth is probably somewhere in the middle. If engineers knew exactly when metal would break, there would've been way fewer aircraft, train and car failures. But they don't. This is why there is a mandatory scheduled maintenance in commercial fleet, INCLUDING PARTS REPLACEMENT, even when it still looks good. People in dealerships are not engineers.
Where can you get a Volt or Spark bike repaired when it breaks? Do you think these companies will be in business in the long term so you can get parts? I would recommend buying an ebike from an established bicycle company at a local bike shop. Even then, who knows if repair parts will be available several years or more later. At least your odds are a lot better and maybe your bike won't end up in the landfill when your bike breaks and it can't be fixed.
I've never owned an orbea so went looking - that's definitely not " any old frame" - to me it looks like a custom fabricated carbon fibre piece of exotica?
So I went looking at their track record with carbon frames , it doesn't sound impressive and nor does their warranty ( read the comments ) https://bikerumor.com/2016/01/14/or...-do-something-you-may-have-never-done-before/. Sure, it's just the internet, but I stand by my original statement that I don't want to be the guy who finds put the latest ultralight ebike frame isn't up to the task.
As to your r+d question, I think giant r+d has relocated to about 20 km away from their main thai factories because they are getting a bit too big to fit everything in what is essentially high value bicycle manufacturing real estate. I think you'll find orbea carbon bikes are made nearby.
First of all, if you don't know how to take care a carbon bike then why go directly to full carbon? BTW, my post #71 https://electricbikereview.com/forums/threads/how-to-judge-quality.26896/page-4#post-184027 mentioned a FULL ALLUMINUM ALLOY at 28.7lb frame not carbon.
And if you want to know about carbon frames, there is not a carbon frame from any manufacturer at any price that hasn't cracked when pressured beyond is limits. I mean they are idiots out there that own a carbon bikes yet don't even own a proper torque wrench. I've owned 4 carbon road bikes, one of them an Orbea, and never had one crack. But then I know how to take care of my bikes Does that mean carbon is "indestructible"? Of course not. And in addition there is a difference between cracking the gelcoat or paint and cracking the carbon fibers. So not all cracks require a frame repair.
Since you mentioned Giant, here are some messages from people with cracked carbon frames and warranty response by Giant. I guess based on your assessment that must mean that Giant makes junk carbon frames and takes hell and high water to honor their warranty. Search bikeradar for any brand for carbon cracks.
https://www.bikeradar.com/forums/viewtopic.php?t=12977284
https://www.bikeradar.com/forums/viewtopic.php?t=13040209
https://www.bikeradar.com/forums/viewtopic.php?t=13062428
https://www.bikeradar.com/forums/viewtopic.php?t=13065233
https://www.bikeradar.com/forums/viewtopic.php?t=12709711
Or for that matter it must mean that Juiced Bikes must make totally worthless junk ebikes considering the amount of posts from people having problems with their ebikes.
And I stand by what I said. The future of ebikes are less than half the weight of current cheap china made ebikes. And I'm not talking carbon ebikes.
ebikemom
Well-Known Member
I asked about the dropout design out of sincere interest and I thought it was interesting to hear a story of a brand's experience developing their ebike product, and thus I shared it here. Bike frame design is beyond the realm of my expertise, so I had no expectations about what the reply would be, or why an ebike frame might benefit from a design that is different from the frame for a conventional bicycle.
I learn new things every day!
Keeps life interesting! Similar threads
