Living Jackson

Benefits of cycling
How Much Does Weight Affect Your E Bike Riding? | EMBN Investigates

How Much Does Weight Affect Your E Bike Riding? | EMBN Investigates


– The goal of any
competitive cyclist is to be as light and as strong as possible, both in body, and in bike. Now, it’s simple physics. The more or less you weigh,
the more or less energy is gonna be used to
pedal your bike uphill. But this is an e-bike ride, who cares? The battery and the motor have
got your back at all times. more energy, free energy. So, who cares about such things
as power-to-weight ratios? (energetic music) Well, we often talk about
the power-to-weight ratio, especially on road bikes,
and on cross country bikes. But what actually happens when you lose a big chunk of your body weight? What’s going to be the
effect on the battery, and your speed up that hill? Well, today we’ve got a real hill, and we’ve got a variety of weights, to see what the difference is
between the climbing speeds, and the drain on the battery. So, how are we gonna do it? Well, I’ve got this specialized Kenevo, which is 180mm travel. I’m gonna be riding in trail mode. The hill behind us is
gonna be about 1,000 feet, which is 305 meters, spread out over 5k, which gives us a gradient of about 7%. The trail itself is gonna
be a mixture of fire roads, and technical single track. Gonna do two climbs. The first climb is gonna just be me, and my body weight, and
my water bottle full. And then the second
climb is gonna be again, myself and the water
bottle, and a 15K backpack, which is gonna be pretty tough. So, why 1,000 foot you ask? Well, it’s about the height
of a World Cup downhill track in terms of vertical descent. So, I’m really interested
to see how much battery the bike uses and how quick it is to get to the top of 1,000-foot, 305-meter hill. (inspiring music) Right, so run one, 1,000 foot
is not an insignificant climb, but during the run I’m
going to be trying to output about 180 to 200 watts through the cranks. My heart rate’s gonna be about 132. So, there’s a bit of …
There’s a quite moderate pace. I’m gonna be going up this hill to kind of sustain that speed. I’m gonna be using the
Specialized Mission Control App, which is gonna give me
outputs on battery usage, how much power I’m putting
through the cranks, and the run time, and the elevation. (exciting music) There you go. Run one, steady pace. 18 minutes and one second. Now, at that climb, I tried
to keep a steady pace, and because it was of
that gradient, you never went beyond the 25
kilometers an hour barrier. So, yeah, 18 minutes, and we’ve used 16% of the battery, so,
it’s about 75 watt hours. Now, the battery on this
bike is 504 watt hours. That means, on a 1,000-foot
hill, I could actually get about six to seven runs done. Which is pretty good for one battery life. But, do you know what? I’m not gonna be doing seven runs today. So here we go, run two. Got the backpack on me, 15 kilos. Now, the boss told me to
go easy with the weights, but this is like having a World Cup downhill bike on my back. (mystical music) Could’ve left a halfway
point with a 15K backpack. I’ll tell you what, it’s quite
a grind, quite different. But, so far, I’ve just about
managed to keep the heart rate, and the watts through
the cranks about the same as my first run without a backpack. I’ll tell you what, though,
you don’t want to try this. It’s ridiculous. To put it in perspective,
my colleagues at GCN, they did a similar test on power to weight a couple years ago,
and they did a 5K climb over a seven degree gradient,
in about 22, 23 minutes. But they were a lot fitter than I am. But if you’re interested
in seeing the time, this backpack on, I can tell you. (mysterious music) Whoa, wow! Oh my God! 20 minutes and seven seconds, that’s over two minutes
slower with a 15K backpack. It was actually quite
different to ride that as well. I was constantly changing
gears to maintain the momentum and the cadence,
so that my heart rate, and remember, the power
through the cranks, was equal to my first run. But, yeah, wow, that’s quite
different to the first run. But what does all this mean? Let’s go to the pub, and find out. So, I’ve been analyzing all the figures over lunch, and I was wondering. You might be thinking:
Why on Earth did I chose a 15 kilo backpack to pedal up that hill? Well, there’s a reason behind
it, and that’s because, me, on a good day, fighting
fit, weighs about 90 kilos. And, to put it in a
mountain bike perspective, Enduro World Series champion, Sam Hill, weighs about 75 kilos,
and World Cup Downhill champion, Aaron Gwin, 75 kilos. So, I really wanted to get
insight to how it felt, going up that hill at different weights. So, as we mentioned
earlier, the more or less that you weigh, the more
or less energy it takes, to pedal your bike uphill. So, what do the figures tell us? Let’s go into the detail one by one. Okay, first up, let’s
have a look at the actual time difference between each run. First up, the run without a backpack was 18 minutes and one second. Now, compare that with a 15 kilo backpack. Two minutes slower. 20 minutes and seven seconds. Now, that’s a huge,
huge margin for one run. You try standing on the side
of a fire road for two minutes. It’s a lifetime. But, I think the important
thing here is that, imagine doing six or seven runs and the time difference it
would be when you do that. Okay, let’s move on
and see how much actual battery was used during each run. The first run, without a
backpack, the bike used 16% of it’s battery life,
so obviously quite a lot. But the second run, with a 15K
backpack, 19% of the battery. Now, that’s actually closer
than I really thought it would be, considering the amount of weight that we’ve put into the system. So, that kinda gets me
thinking: Well, if the 15 kilo backpack only uses 3%
more battery, then … Kind of implies that a five
kilo difference is only gonna make a one percentage
difference in the battery life. These are rough figures,
I know, but, from that, it’s made me think that: Well,
if my bike was five kilos lighter, then it’s only
gonna make 1% difference? That’s not very much. And then, it also makes me think that: If I was to lose 5% or five
kilos of my body weight, then, that’s not gonna make
a huge difference either. So, maybe we should be looking
at watt hours used as an indicator of battery life instead. So, let’s have a look at these numbers. Now, without a backpack, 75 watt hours. That’s quite a good chunk
of battery life, yeah? With the backpack, 89 to 90 watt hours. Now, Specialized Mission
Control App is really good at giving you all this
data, to analyze this. And, it’s got me thinking:
Well, that’s quite a big difference, actually. You’re looking at the difference between, if you’ve got a 504 watt hour battery, you’re gonna be able to
get six to seven runs without a backpack, 15 kilo backpack. Yet, if I put my backpack on, that’s gonna knock it down to about five to six runs. So, you’re gonna get a whole 1,000-foot difference between that weight. So, it is actually quite significant. So, I did the two tests, and then I sat around thinking: Well, I’ve still got a ton of battery left. So, What would it be like if I
stuck the bike in turbo mode, and actually buried myself,
gave it maximum beans on the climb, and that’s what I did. So, my time was actually 13 minutes. That’s a whole four
minutes quicker, in turbo, than it was with me in trail mode and, what was quite interesting,
was that I actually only used 100 watts of battery during that run. So, I could actually get
five runs down on turbo over a 1,000-foot hill,
which is actually a load more than I thought I could. Obviously that was on a
smooth kind of gradient. So, There’s loads to think
about here, and we’re really gonna be exploring this
over the next few months, and when it comes to e-bikes
and battery life and weights. So, there you go. If you want to see more
about analyzing e-bike runs, there’s a good run on
downhill versus e-bike, which is down here. If you want to see more
technical things on motors, there’s this video here to check out. If you like this video,
and would like to see more, please give us a thumbs
up, and I think that the subscribe is around about here somewhere, right Tom?

36 comments on “How Much Does Weight Affect Your E Bike Riding? | EMBN Investigates

  1. Great videos ! Inspired me to buy my first emtb tomorrow! Going for a Trek Powerfly 7 hardtail 🙂 Is this a descent choice for a newbie who wants to both commute about 24 km everyday and go for some cross country rides?

  2. So how much load (weight) could you put on an ebike motor, how heavy is too heavy for bosch, shimano etc.

  3. For those of us who have that extra 10-15 kgs, we welcome you to the big guy club (when you have the pack on). I'm looking forward to the series. When I do longer rides on my road-e, I have to do a lot of battery life maintenance. Ride takes longer but I get a nice workout.

  4. So it's good news then……….
    ….. you can stick to the pies and beer diet! One point worth remembering, some people carry more weight in the form of muscle. Ok, the body needs fuel and oxygen to run it but that muscle especially if in the legs rather than upper body, is going to give you more power at the crank. If how ever it's fat around the middle, stick the bike on turbo mode – after-all, you are out exercising rather than slumped in an armchair 😎

  5. Set up can make a massive difference, this week I have done a loop of light trails and road 54 miles (fitness run) on a Scott e genius 700 [email protected], same run @30 psi and using the frame lockout where comfortably possible and I gained 17% range. How you ride the bike on the trails has a decent effect on the drain on the battery. Nice to know eating a few pork pies isn't going to effect the range too much……Great video keep em coming.

  6. you didn't use 3% more power – you used 18.75% more battery power. going from 16% to 19% is not 3%, if you know how it works. think about it – going from 10% use to 20% use means you're using power TWICE AS FAST, so it's 100% more use, because the extra 10% is "100%" of the first 10%. so from 16% to 19%, the 3%-extra is "18.7%" of the 16. math is 19/16=1.1875, ergo 18.75% more power being used. THAT is a BIG difference…..

  7. I second what Greg R says. 3% over 16% base is nearly 20% increase. Which is a bit more than the proportion between the added weight and the bike+rider weight (15/(90+20)). Lest we forget that, if you managed to output the same power, on the second run you generated it for 2 more minutes; in other words, 2 over 18 min=11% more human energy. Looks like in the second run the load share was a bit more biased towards the electric motor.

    So yes, weight is really important when cycling. However, being myself some 6kg overweight, I don't care that much for the 500 grams of the latest carbon fiber stuff.

  8. Really interesting test, basically still means llit pays to be lighter but being heavier isn't as big a handicap as expected on an e-bike. Love these tests, keep them coming.

  9. so you get more than double the elevation on a brose than a shimano, we have to take 2 batteries with us for a decent day out. would be good to see you replicate that same run on a bosch, shimano and yamaha to get a real comparison?

  10. I feel it. At 225lbs kitted I have no chance with my riding buddy at 135lbs (same Levos). We've learned to ride together, cast the frustration on both sides. Also my gal at 140lbs kicks my butt too. The new 152mm Miranda KTM crank arms are the best mod yet (well, after the limiter hack).

    Do a test: Fit 150lb ebike rider vs fit 150lb regular bike rider. I swear my buddy could smoke NinoS

  11. If know I am generalising here, but doesn't simple physic determine the power required to 'force' an item up a hill? Let me be wild here and pretend resistance is equal and uniform during the entire course of the change in elevation. This means we need (X) force to push the mass up the hill. Add mass and you will require more force. It has to come from somewhere in the system, being either from the bike or the rider. In this case, the extra weight showed as being more power used by the bike and the same power applied by Steve, but for a longer period, which equates to more energy used in total by both bike AND rider. I suggest doing a test in turbo mode, but aim for the same time. You can then see the change in the required output of the rider. On trail mode you have more than one variable being the power the bike applies relative to pedal pressure and time. One must also consider the whole imbalance of having a 15kg hunchback…..I think strapping it to the bike would change the stats as the extra 15kg actually provides another variable in the power generated at the crank. (Ie 15kg = Approx 150nm of extra torque in the down stroke.). Overthinking it, but it is a very complex question as there are so many variables. Great food for thought though!

  12. I have been riding E~fatbike for just over one year and have lost 55 pounds. I have noticed better mileage with the lower body WT. to date 2,500 miles
    Love the E~fatbike 👍

  13. Obviously its not a simple as that…someone who is 15kg heavier simply because of fat is used to that weight and its more comfortably spread over the body.
    Im 20kg heavier than a friend, other factors come in to play, the bike is lighter to me..my legs are used to my extra weight.

  14. It was always going to make a fairly significant difference – efficient ebike riding is all about maintaining momentum whenever you are using the assist modes. I’d like to see a comparison video using tyres with low rolling resistance (maybe light XC) versus chunkier more aggressive tyres (say enduro or downhill) as I think rolling resistance makes a bigger impact on battery life.

  15. I just returned from a trip to the alps and the whole week was about battery management. This has raised a question that could be answered in a nice video.
    Does it matter in battery life if you go straight up on a higher mode or take the long fire road around on a lower support setting?

  16. Good one Steve. Which all goes to prove why a rider like me who is closer to a 100 Kg rides Turbo uphill just to stay with my skinny mates. One of the joys of Pedelecs, you can choose the mode that allows you to ride together.

  17. The video also raises the point that one battery size does not fit all. As a 100Kg rider I need a bigger battery for more range, especially in winter. The extremes I hit over varying rides using mostly Turbo are from 17 to 34 miles range from 500 Wh or roughly 30 to 15 Wh/mile and typically 1,000 ft per 10 miles.

  18. The watt/hour consumption is probably a better way to calculate the relative energy use. 75 w/h without backpack, 90 w/h with pack. 100 w/h on Turbo. Total battery capacity was 504 w/h.

  19. I was actually thinking why did you go to the pub to get a pot of tea?! Surely two climbs deserves a pint

  20. Steve, did you have a tuna salad with your green tea at the pub after 😊 your looking ripped since doing all these ebike climbing vids…

  21. 15 kg is a fair wack , there's no getting around the fact you must expend more energy to move more mass .

  22. My son weighs 8 stone! He can’t keep the front wheel on the ground on climbs. 😂. On a trip to bike park Wales he did 1 full run up and down more than me. I weigh 13/5 stone.

  23. The point every one is missing here is power to weight ratio. A pro weighing 150 lbs puts out sustained 375 watts for say up to an hour . If your a chubby 200 lbs weekend rider only able to put out 240 watts for an hour you’d have to drop a 100 lbs to even come close on a similar climb to matching his speed .

  24. Hi,

    I would of done the weighted run first, then the unweighted…. you’d feel better on second run and still have your results.

  25. OK, so I ran into a bit of weight problem and suddenly I was 94Kg (187cm height). I still exercised every day, lifted weights and either did cardio or rode my bike (mostly my pedal assist).

    Then I dropped to 77Kg (17kg loss) . Battery use radically dropped. Of course DH improved -> better breaking and better traction. And climbing obviously improved radically too. Also dropped my water from 3l to 2l as I just don't sweat that much anymore.

    Now on to the bike. I am actually thinking of replacing my 180/180mm travel Haibike (25Kg?) with a Pivot shuttle (saving an additional 5Kg) and have a serious look at ALL my gear to see where I can shave an other Kg or more.

    I never was a weight wheenie, and I really though that with an e-bike it just didn't matter, but it does. It does matter a lot.

    My other bike is a Santa Cruz Nomad. Less than 14Kg 🙂 . The funny thing is, that after my weight drop, I weight less on my ebike that I did on the Nomad before.

    Just my 2c on the weight on e-bike debate.

    Comparing to other riders: I know 2 guys who are really skinny. They were more than 20Kg lighter than I was. When I was literally pushing it out of the park with 0 battery left, they still had 2 bars, even though we ascended/descended with the same speed and on the same settings with the same motor/battery pack.

    BTW, my average e-bike ride is about 1.5 hours with a 700m (2100ft) ascend. That's the average "ran out for a local ride" distance/altitude. Park days are 1000-1200m or more and I would switch to battery #2 after about 1000m of climb. 1 bar = 200-300m climb (really steep muddy single track). On fire roads you can climb 500 on 1 bar. Bosch CX 500Wh battery, EMTB mode.

  26. Why didn't you ride with the weight first? You degraded the results by riding it w/o wt first. Weird
    Our restriction is 32kmh here in Canastan. 35 would be nice though…

Leave a Reply

Your email address will not be published. Required fields are marked *