Bolt On E-Bike Motors Explained | E-Bike Fundamentals


– One of the most
frequently commented upon issues on E-Bikes is the cost involved. So today let’s have a look at some of the alternative ways of converting your mountain bike into an E-Bike by way of after market, mid drive motors. (techno lighting sound effects) Now the bikes we ride here at EMBN are incredibly sophisticated systems, the fully integrated
motor battery and chassis have been created not just out of the best design and best materials, they’re very efficient, and they also use the best E-Bike geometry finishing and componentry. Like I said, they’re very much a system rather than a collection of parts. And they’re also very dynamic in the way the power’s transferred via torque sensors. However the bikes we ride don’t actually come cheap, but there are alternative ways to avoid that significant cost involved in buying that mountain bike. And that is by converting your existing mountain bike into an E-Bike by way of these retrofit mid drive motors which I mentioned earlier. So what do they look like? Here is a Paradox unit. This comes from Greece. As you can see, it’s pretty dinky. Pretty small. Behind me I’ve got a selection of others, this is a Bafang motor which is bolted to a downward bike and we’ll talk about how that power is transferred there later. And over here is a Lift MTB motor which comes from France. It’s a little company in Northern France. And that obviously controls the leads which power that. (upbeat techno) Now one of the first things you need to be aware of with these retrofit kits is they’re not all peddle assists. A lot of them are actually
throttle operated, which means they’re not limited in the speeds they can do. However there are some kits, such as the Bafang, which you can switch between throttle assist and peddle assist. So that’s quite a neat system. But I’ll go into that
a little bit later on. (upbeat techno) So why are we talking
about mid drive motors, not hub drives? Well there’s lots of excellent hub drives out there, both front and rear wheel drive, and they came in a vast
array of power outputs. And when it comes to peddling fire roads, or smooth single track or commuting, they’re very very good at doing that job. However the strength of a mid drive motor is that the power to the rear wheel is controlled by the same gears, the chain and through the pedals, which means the ratios are far more suited to off road use than the hub drive, which has got just a single gear ratio, which means that on
the steeper hill climbs they’re not quite as
good as that mid drive with that range of gears. The other thing with the hub drive is that because all the weight is located in the middle of that wheel, all the impacts are going to go through the rider, whereas the mid drive unit is centrally placed, which means the weight is, not only is there a low center of gravity, but the weight is distributed more evenly so that there’s a good balance of the whole chassis and
the rider on the bike. (upbeat techno) Yes! So how much do they cost? That’s big question. Now for say a 250 watt motor, which is quite a low powered motor, about £500 but remember you’ve got the cost of the battery
to go on top of that. Plus remember there’s
the cost of your bike. Now as you go up in power, they do become quite expensive so you can spend about €3000 for a really powerful motor but remember, the more powerful the motor the more weight because less range. But they still are a really good option for many people as a starter because you can buy, say, a hard tiller new or
second hand hard tiller for about £600. By the time you fit an after market kit you’ve got a dream bike for about £1600. On the other hand you can choose like my mate has done and he has bought a
second hand downhill bike. This cost him £900 off eBay, which is an incredible set of forks, a great chassis, and he’s bought his
Bafang motor from China, that’s £200, and he’s got some batteries
he bought himself, with his own battery management system. So you’re looking at £1500
for a complete biker, and it’s a really really
good uplift option. What though if you were
to have a new bike, what if you want to have a new bike with a custom kit? Well there’s lots of good bikes out there which you can buy, such as the Vita Sonax, £1700, and you know by the time
you bolt the kit on, that probably takes us up to £2700, I’m thinking well there’s this really good custom E-Bikes, such as the Haibike or the Canyon Spectral on the market for £2900. But I think if you’ve got £600, and you want to convert your existing mountain bike then, I think a mid drive kit
is a good way to go. (upbeat techno) Fitting, yes. That is obviously a crucial question. And the answer is yes and no. It all depends on the motor you’re using, and the type of battery you’re gonna have with that motor. And it honestly depends on whether you’re going to be using a hardtail or a full
suspension mountain bike. But the detail involved here is a lot of these after market motors not just through the bottom bracket, and you do have to have
a 68 to 73 bottom bracket for these motors to fit. (upbeat techno) Yes, where does the battery go? Well if you’ve got a hardtail, you’re very lucky that can be bolted onto the inside of the downtube and it’s actually quite a neat system. However, if you’ve got
a full suspension bike, most of the time you’re gonna be carrying the battery rams in a backpack and they vary in weight
from brand to brand, but you’re looking at 3 kilos. However, my mate here has got his system and he carries his
battery in his backpack. This is one of his packs. That is about six miles. But he usually carries about three of those on a big ride. (upbeat techno) In the battery goes. You zip her up. So I’m not really very
experienced at this, but I do know that you
put your backpack on. Obviously you’ve got your helmet on. So then the power lead connects to this power lead. So there you go, and the bike is actually now ready to go. It’s got pedal assist, remember on this Bafang motor, and also throttle assist. So I’m thinking that if
I press that throttle, (laughs) Oh my God. Off you go. So I think you can see, I’ve given a demonstration there of how these bikes work. You can actually configure how much output comes from the motor by way of software. Now Spoons’ bike here, he’s got a system where
it’s 20% pedal assist and 50% throttle assist. So if you’re pedaling up the hill and need pedal assist, and you want to turn, you just simply go to throttle, which is 50%. That overrides your pedal assist. You might as well not pedal. And if you want to change that, well you can do that back at home, unless you’ve got a display on the bike here. This system over here, the Lift MTB, as you can see it’s got a really neat display on the handle bar. Together with your throttle, with the amount of battery on there. And yeah you can control the amount of output through the motor simply by changing that on the handlebar. (upbeat techno) Yes, weight is really important. And don’t expect to see many of these after market motors coming
in under the 3 kilo mark. And remember the more power, the more weight and the less range, etc., etc. However this motor here, which is this beautifully made Paradox Hermes from Greece, look at it, it’s so dinky, it’s so well made. That comes in, remember there’s all the parts as well, the chain wheel there, and the leads, and the fitting, comes in about 2.6 kilos, so how does it compare to say, a Shimano, or a Brose or a Bosch. Well this is the very latest Brose motor, Brose Mag S, actually because there’s a cover on there, which means the motor is actually a lot smaller than that, and that comes in about 2.5 kilos. Now when it comes to the weight and the power and the torque of each of these after market motors. Later on in this video, I’m going to be going
through some of the figures of each of these systems. (upbeat techno) I think it all comes down to the amount of power you put through that transmission. If you’ve got a very powerful motor, then something’s going to chew up your transmission. You also want to be very careful with the chain line. Now some mid drive after market bikes haven’t got a very good chain line which obviously can put a lot of stress on your chain and gears. And when it comes to waterproof-ness, you need to be very
careful in the fine print of some of these motors. Some of them say they’re waterproof, some are water resistant, but again it comes down to the way you use them, how you use them, and how much power is
on each of the motor. (upbeat techno) Yeah so this is where it probably gets a little bit messy. Now as I mentioned earlier, a lot of the after market, mid drive bikes are 250 to 500 watts, there are ones which are more, 750, 1500, as I mentioned at that point they do tend to cook the transmission on the bike, but not only that, you need to be careful with the battery involved with the bike. Now you need to be very careful. Now Spoons here, who’s got this bike, has got a lithium-polymer battery. And with a battery management system. Now you need to be extremely, extremely careful when it comes to batteries on these
after market mid drives. Because you really need to know what you’re doing, and be aware of the dangers
involved in charging, of mixing and matching these batteries. Now when it comes to things such as the fitting, now as you can see this Lift MTB motor here has got a pretty
good ground clearance. This is where the ground clearance would normally be, between the bottom of the
chaining and the floor, you see it’s neatly tucked out of the way there. All of this depends on what frame design you’ve got. What you’re trying to avoid is having something that’s low down, that’s just going to
be catching the floor. Now on the other hand, Spoons’ bike over here has got probably one of the neatest built on kicks I’ve seen on a bike. But still you can see that that motor is significantly lower than the chain line. Which is going to come into contact with rocks and roots on the trail. At the same time we need to put this all in a context, obviously the bottom bracket height in the first place is really important. Like I see the bottom bracket height on this 224 is actually quite high, I’m guessing it’s in the 360-370 area. So relative to maybe
the bikes that we ride, about 350 millimeter
on the bottom bracket, then you know it’s
actually probably alright. (upbeat techno) Yeah you need to ask yourself do you actually need more power on your E-Bike? Now there’s a fantastic quote by Matia, who owns Lift MTB in France, who make these after market models. They’ve actually got an incredible website you’ve got all the answers when it comes to after market mid drive bikes. Just check that out. But his quote, he says that: Says it all. (upbeat techno) Right let’s have a look then at what after market kits are available to bolt onto your bike. Starting off with the Bafang. The after market kits come in the BBS01, the BBS02 which is fitted
to Spoons’ bike over there, and the BBSHD. Now when it comes to the power outputs, they are from 250 up to 1000 watt motors, and the torque, from 80 Newton meters
up to 160 Newton meters on the top end motor. As I mentioned earlier, they’re both pedal assist and throttle assist. And the weight of the motor from 4.8 to 5.2 kilograms. So not light, but as I said they give you that pedal assist which is a really good option, and yeah definitely one to check out. Now the prices on the
Bafangs start around £600. At the same time, this is the French made Lift MTB. These start at about €999. So when it comes to the power outputs of the Lift MTB, remember this is a throttle only unit. The watts is 450 watts
nominal to 750 watts max. And Newton meters is
80 to 90 Newton meters, at the rear wheel. It’s a pretty light system, 3.2 kilograms. Obviously there’s the
weight of the battery to go with that, and the good thing about Lift MTB, it’s got a vast range of batteries raging from about 1.1 kilos up to 2.9 kilos. Which brings us to the Paradox Hermes. It’s the Greek made beautiful unit. €3000 euros for this system. But I can tell you, it is a very very well made unit. This too is a throttle only system. It’s 1200 watts nominal, and 130 Newton meters of torque. The battery is 744 watt hours, so that is actually pretty similar, it’s actually a bit more than the one on the new specialized Turbo Levo. And that goes into a backpack, and I think Alex at Paradox has got his own backpacks to go with that. And finally the Ego kit. Now the Ego kit is the
one that Martyn Ashton used when he rode down the World Cup Track at Fort William. And also when he went out to Whistler which was custom fitted
to his Canyon Sender. Now when it comes to Ego kits, there’s two kits available, and they are 2400 watts and 3400 watts. Now I’m just thinking, oh my God, that is just like massive. When you think that
the bikes that we ride, a specialized Turbo Levo
is 250 watt nominal. Now we look at the prices, €2999 or €3999. €2999 or €3999. The weight of the motor is 3.2 kilograms, but it’s 5.5 kilograms on the bike. That’s a significant amount of weight. The weight of the battery, 5.9 kilograms. So there’s a huge weight involved, like when I mentioned earlier, when you’ve got more power, there’s more weight which means there’s more drain on that battery. That’s all we’ve got. I think I’ve covered most things in simple terms, obviously there’s lots of detail and lots of other E-Bike motors on the market. I’m sure there will be comments below which remind me about these, but like I said, this is just a basic overview of after market E-Bike motors. But please, let us know your comments below, so we can get this conversation going about these retro kits, if you want to see more
about E-Bike motors, the custom E-Bike motors
which we use here on EMBN, check out this video here. Don’t forget, you can like, share and subscribe to EMBN to make sure we can keep these in depth videos coming. Thanks very much.