How Does Gearing Change An E-Bike's Ability To Climb

How Does Gearing Change An E-Bike's Ability To Climb

E-Bikes come with a vast array of gearing so you’d be forgiven for thinking that you’d be able to get up any climb, no matter how steep. But that’s not always true…. Steve experiments with a variety of different gear combinations on his e-bike to see how they compare on steep climbs.

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A Bosch motor has easily converted front chainring to best tailor your gearing to the type of terrain and riding that you do. Level terrain and more fire-road climbs might mean that you should consider a larger front chainring, whilst steep and technical climbs might be made easier with a tiny gear.
If you do swap to a smaller gear you’ll get a longer battery life out of your motor because you’ll be able to ride uphill in eco or normal mode rather than turbo.
Additionally for extra steep ramps you might be surprised that lowering your saddle and altering your normal technique could allow you that extra grip and balance you need to overcome the gradient.

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Readers Comments (50)


  2. If I cant climb it on my ebike after 3 tries then time to try another way 😉

  3. Can you make the same video using the levo pls

  4. BBSHD and a Rohloff will climb anything! 8)

  5. You could eat your f**kin’ dinner of the Shimano 52t on the back I’ve got, at least if I flat, I can run on the cassette!

  6. Brilliant, thanks again Steve. Now to find a 14 tooth sprocket for my Bosch CX

  7. Thanks for the video!- I changed my Haibike Bosch Performance CX 18T to a 14T WOW! what a difference! Opened up a whole new style of riding! Bought the 14T from Worldwide cyclery online for only $23 ! it is made by sram – super easy to change and no problems at all with install- don’t use the alum spacer that comes with it though. Only downside is I don’t have a bash guard but honestly- don’t need it.

  8. You failed to mention that the Bosch sprocket runs the 2.5 ratio equivalent of a conventional front sprocket size.  So your 14t is the equivalent of a 35t conventional size. 15t = 37t, 16t = 40t etc.

  9. shellshock proppie February 3, 2021 @ 8:22 pm

    Funny I changed my gearing and need it software update to get the gearing and the reading correct

  10. 16:48 = 1:3
    14:42 = 1:3

    Same gearing. The Bosch has a internal gearing for the output. Notice the chainring spins faster than the cranks…

  11. My 2016 Scott genius 910 is 11/42 and flys up hills

  12. You are clueless that Bosch has internal gearing in this engine with 2.5 ratio. So in fact your front chainring is ~37.

  13. Rocky mountain power play?

  14. just buy specialized bikes and leave bosh to kids

  15. I watched this video with great interest. I ride hills here in the tropics of Panama that are asphalt and very often have long slopes of 20-25% but even shorter sections of 30-35%. I ride these on my standard bike in a 26/42 f/r gear. I am looking at getting an e-bike so my wife can accompany me on these non-technical rides. One I am considering has a 1000W Bafang motor and the lowest gearing will be 44/48 (160 Nm torque). The other has a Bosch 16/46 setup (350 W, 75Nm) Do you think either of these bikes will have a problem with these hills? Thanks in advance.

  16. I would just like to say that I think Mr. Jones is one of the finest, most engaging and lucid presenters of the cycling community.

  17. can someone tell us why there is an idler tensioner like cog above the motor on the one bike? is that to help in chainsuck so you can wear the chainrings longer?

  18. Sebastian Engelmann February 3, 2021 @ 8:32 pm

    Huh i even have a 34 teeth chainring on my stolen bike, so i had even smaller gearing. It climbed a very steep section with a breeze, leaning over the bars and pushing, but i made it 😀 The ground was dry and dusty. I hope i get this nice bike back from police or atleast can buy another one with the insurance. to bad i just changed to tubeless tyres…..

  19. Great video. I have Cube Emtb with Bosch Performance Line CX. Can you please tell me or give me a link were I can find bottom protection of Bosch engine like in your video at 1:50 mark. The orange one… tnx

  20. Thanks for the Video mate , I ride a Levo and don’t mind the standard gearing but am keen to try a 30T front chainring simple because as you say that it’s way easier to top out the speed limiter with the taller gearing. Love my single track cheers

  21. Bosch… Crap.

  22. Juan Carlos Alpízar February 3, 2021 @ 8:35 pm

    At first I was extremely confused, why would you put a 16 sprocket in the front, and make the bike insanely slow overall? Then I read about the tech involved to make a 2.5 ratio in the motor, that’s awesome and cool tech indeed! Does this process has a further impact on battery life than a standard chainring?

  23. Is it normal that you lower the saddle position with an ebike on steep climbs? Is it because otherwise the front wheel would go up?
    I mean with the shorter position it seams like its really uncomfortable for bent legs.

  24. I’m a heavier rider and transitioned to an ebike a little while ago and love it. I keep up with my much fitter mates and we all have a great time out. Interestingly I switched to open my suspension on tighter trails (seat up though), and I reckon it climbs much better, still lock out on formed fire trails. Love the show and tips, making me a better and fitter rider too.

  25. I tried to fit a 14t front sprocket on my Haibike XDuro All Mntn instead of the 15t it came with (I have also replaced the 10-36t cassette with a 10-42t) but found the chain rode on the inside lip of the bash-guard and jumped the sprocket under load. I believe the smallest sprocket may be 15t. How did you manage to fit a 14t sprocket on your Bosch motor?

  26. How does having a smaller gear up front, compare to say a 34 tooth, if you have to pedal with the motor turned off.

  27. so how many watts is this pushing..?

  28. I went from 15T to 20T for commuting Trek powerfly5 Bosch CX Schalbe 29×2.35 road tyres. The bike is much nicer sitting in the middle of the cassette. Speedbox2. I stick to 30km/hr on bike paths but when I go on the open road amongst cars I can hopefully go a bit quicker.

  29. Simonas Dailidė February 3, 2021 @ 8:56 pm

    Nice trip!

  30. 👍👍👍👍👍👍👍👍👍👍👍

  31. Donald Bartholomew February 3, 2021 @ 8:58 pm

    They have to get rid of that 25kph restriction. There are companies that make unrestricted e-bikes that are really awesome bikes

  32. I notice the Gepida has a very small front cog as opposed to most other emtb. Should I avoid this if I just want to do easy biking and not extreme climbs like in your clip? Thanks for the info. Very helpful

  33. Super informative.

  34. Shut up. Got an engine. Always ‘aving a ming you lot. Got a motor so crack on. None of you have ridden anything because its all with a motor. But it’s cute that you think you have.

  35. Yamaha 2x is sooo wonderfull.

  36. Technical skill and ability to read the hill in advance really help, I see people all the time getting to a steep bit and giving up when all they needed to do was look ahead and be ready in the right gear, same for any bike riding road, mountain or trail . Smooth transitions make for an easier ride regardless of surface

  37. Whats to dislike here? Why the thumbs down? 😕

  38. Brose S with 38 front and 11-42 rear. Usually no problems up to 24-26% grade, but not doing really heavy flow uphill.

    I confirm that the shorter the available gears, the longer the battery charge life.

  39. Electric Mountain Bike Network February 3, 2021 @ 9:01 pm

    Where is the steepest place you’ve ridden on an E-bike? Let us know.

  40. I have an emb that has a de-restricter fitted. Im running out of gears at 26ish mph and wondered if fitting a larger chain ring would give me just that extra speed to get over 30 comfortably.

    The bike i have is a Rockrider E-st 520 with 11-42 cassette , chain ring is 34

    This is for private off road usage


  41. Why don’t they do what they used to and have multiple gears in the front just like the back?

    Cuz I had old bikes with 18 or 21 speeds. Lol

  42. love my Bafang BBSHD and my e13 9-46 Cassette with 42 front Cain ring.

  43. There is a serious and surprising fundamental ommission in this article, i.e. the chain ring on the Bosch system actually rotates 2.5 times for every turn of the pedals so in effect a 14 tooth chain ring is equivalent to 35 teeth on a normal system.

  44. Hi. Love your channel. I am about to buy KTM macina ride 272 to cross country porposes. I am wondering if I am buying the right ebike. I will not intend to go to trials cause I am not a professional of mountain bike. I just wanto enjoy riding a mtb to be in contact with nature. To get to the park I need to go by asphalt road and climb some hills with 10% gradient. Is this KTM machine ride 272 up to my needs? Thank you in advance.

  45. Hi, if you test a levo with blevo app you can see how much what you consumed by each climb so nice feed back also W/km and after the ride a lot of info gives you an idee about you and the bike

  46. What about Shimano Steps E8000 gearing, is there a possibility to use a smaller chainring then 34t ?

  47. guys been searching for gearing for my allmtn 7 would love to know how to add or get the 48 tooth rear

  48. Hello!! On the Haibike XDURO 8.0, taking the original Sprocket how do you deal with the space between the engine and the chain ring, did you get a Spacer, where? (I know a version that the spacer was made from another 14 without the teeth’s…) Thanks for your attention, Regards, Pedro

  49. What a pity you didn’t tell what power mode was the motor!

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