Changing tires/wheels on bosch ebike

[Motodaddy]

So I am looking to change my tires/rims on my e-bike from 622-42 (smart sam) to 584-60 (super moto x). According to the Schwalbe site the circumference of the 622-42 tire is 2230 (710 dia) and for the 584-60 the circumference is 2240 (713 dia). Assuming the wheels fit my frame, how much of a difference could changing to this tire combination with a 3mm diameter difference make to the Bosch motor? According to my local bike shop the Bosch motor is so finely calibrated by sophisticated German engineers that it will somehow burn itself out if I were to make this change and I would void my warranty. I can understand how a vastly different wheel circumference would throw the speed and range functions off (although 3mm is negligible, in my opinion and is within expected tolerance range of manufacturing, tire pressures etc). I just can’t at all understand how making this wheel swap would affect the Bosch motor in any other way. The only other factors would be torque/rpm and in the real world rider weight, road surface/condition, gravity, etc would introduce way more variation that a motor would have to respond to than a tire swap could introduce. Is my Local Bike Shop mechanic smoking too much or is there something to this??

 

[Motodaddy]

A 3mm difference in diameter isn't allowed? Interesting... For fun, ask your mechanic which winter tires are supported. Then calculate the difference in diameter.

Yup, I told him the diameters were essentially the same and he was going on about how bosch calibrates the motors precisely for each wheel type even if the diameters were the same. This is the part that really seems like total BS. In any case I just went for a ride on the super moto x.The ride is definitely more comfortable and subdued in a way. I definitely heard the motor whirring but now because of this mechanic there’s a voice of doubt “is it working too hard?” “Is the motor going to explode?” Anyways I guess I’m looking forward voice of reason here that seconds my notion that I’m not doing anything crazy here.

 

[rich c]

I have super moto X on a 2016 XDURO Full Seven S RX. Over 1,500 miles and no issues.

 

[Johnny]

So I am looking to change my tires/rims on my e-bike from 622-42 (smart sam) to 584-60 (super moto x). According to the Schwalbe site the circumference of the 622-42 tire is 2230 (710 dia) and for the 584-60 the circumference is 2240 (713 dia). Assuming the wheels fit my frame, how much of a difference could changing to this tire combination with a 3mm diameter difference make to the Bosch motor? According to my local bike shop the Bosch motor is so finely calibrated by sophisticated German engineers that it will somehow burn itself out if I were to make this change and I would void my warranty. I can understand how a vastly different wheel circumference would throw the speed and range functions off (although 3mm is negligible, in my opinion and is within expected tolerance range of manufacturing, tire pressures etc). I just can’t at all understand how making this wheel swap would affect the Bosch motor in any other way. The only other factors would be torque/rpm and in the real world rider weight, road surface/condition, gravity, etc would introduce way more variation that a motor would have to respond to than a tire swap could introduce. Is my Local Bike Shop mechanic smoking too much or is there something to this??

Quite honestly that calibration argument is BS. If these motors didn't have internal protection I may have bought that (still wouldn't).

The only reason that comes to mind is the obvious speed limit problem since the controller needs the circumference on top of speed sensor input to calculate actual speed. So by changing rims you can potentially "fool" the system.

If I were you though I would just change the tires. I don't know what model your haibike is but even I am considering going for 622x55-60 for my Xduro Cross.

 

[Motodaddy]

Another idea: is it a Speed Pedelec? Those require an EU Certificate of Conformity. Ever seen one? I’ll enlighten you: it’s mandatory for the manufacturer to list every single tire width and size. I’ve seen the COC for several Bosch powered bikes and they usually have a range of tire sizes (just like other bikes subject to a COC). Once again, it’s to account for winter tires...

It’s not a speed peddelec, I’m in Canada so those are not technically not legal. I did not get a certificate of conformity for my bike or a range of tire size. I get that in a high speed application there may be more strict regulation.

 

[Motodaddy]

Quite honestly that calibration argument is BS. If these motors didn't have internal protection I may have bought that (still wouldn't).

The only reason that comes to mind is the obvious speed limit problem since the controller needs the circumference on top of speed sensor input to calculate actual speed. So by changing rims you can potentially "fool" the system.

If I were you though I would just change the tires. I don't know what model your haibike is but even I am considering going for 622x55-60 for my Xduro Cross.

Thanks for the sanity check...I agree, total BS but I wanted a second opinion.

I thought of just changing the tires for 622-50 big bens and I might still do this eventually for my 622 rims for fun. As of now I’m completely sold on the 584-60 supermoto x’s. I had a ride this morning and I am so amazed at how these tires have completely transformed the bike. 30psi they are so smooth, comfortable and surprisingly fast for such chunky looking tires.

 

[Alaskan]

I swapped out the Schwalbe Marathon Plus Tour, Flatless, 700 x 42s that came on my bike for a pair of Schwalble Big Ben Plus 700x50s without having to change out the original Alex rims.

That bumped my tire diameter from 1.6" to 2" allowing me to run lower tire pressure for a suspension effect and more efficient ride on gravel/dirt trails, quieter ride on the road and all around better grip. On the Nyon I was able to enter the new tire circumference for display accuracy.

 

[Motodaddy]

I swapped out the Schwalbe Marathon Plus Tour, Flatless, 700 x 42s that came on my bike for a pair of Schwalble Big Ben Plus 700x50s without having to change out the original Alex rims.

That bumped my tire diameter from 1.6" to 2" allowing me to run lower tire pressure for a suspension effect and more efficient ride on gravel/dirt trails, quieter ride on the road and all around better grip. On the Nyon I was able to enter the new tire circumference for display accuracy.

Awesome, I appreciate the feedback on this. I was originally looking at the Big Ben plus 622-50 and had them on order last week but somehow they lost the shipment. Tried to reorder but now they have no stock. Will definitely consider these formy original Alex Rims when they are back in stock.

 

[Scooteretti]

@Motodaddy, Bosch allows you to change the setting for the circumference by about 5% to compensate for the difference between tires etc.... No you won't damage your motor and yes this can be done.

If your bike is equipped with the Intuvia display you can easily change this yourself and if your bike is equipped with the Purion display a dealer will need to connect into the bike to do this for you, as the Bosch dealer software is required on that display.

I've been meaning to do a video of this anyways, so today was the day. Here is a link to our Youtube channel that will walk you through the steps.

Hope this helps out,


Will
shop.scooteretti.com

 

[Motodaddy]

@Motodaddy, Bosch allows you to change the setting for the circumference by about 5% to compensate for the difference between tires etc.... No you won't damage your motor and yes this can be done.

If your bike is equipped with the Intuvia display you can easily change this yourself and if your bike is equipped with the Purion display a dealer will need to connect into the bike to do this for you, as the Bosch dealer software is required on that display.

I've been meaning to do a video of this anyways, so today was the day. Here is a link to our Youtube channel that will walk you through the steps.

Hope this helps out,


Will
shop.scooteretti.com

Hey Will,


Thanks so much for this info! Really appreciate the response and I’m happy to hear from a reputable dealer that my motor will not be damaged by this change.

Also, coincidentally I purchased those super moto tires as a package from scooteretti online shop (I was the one asking about the tube compatibility). Thanks for the excellent service and responsiveness to my questions.

 

[Scooteretti]

@Motodaddy awesome timing and appreciate you buying those tires from us! Keep us posted on how you like the tires. We love them and you’ll really be impressed with the life you will get from these.

Let us know if we can ever be of assistance!

Will
Shop.scooteretti.com

 

[Motodaddy]

So here’s the finished product with fat 29r fenders added. I’m loving this for the streets of Toronto in spring (also known as construction season). The whole bike no longer rattles going over cracks, potholes and manhole covers.

 

[Alaskan]

That looks totally boss! Those tires look great. Hows the ride? Pros and Cons? What model Cube is that anyway?

My Cube is a Touring Hybrid Exc 500. One suggestion I might offer. I suspect you will find the original fenders not quite wide enough to really keep you dry on a wet road. When I went with the wider tire, I went the extra mile and got wider fenders too. It can make a real difference, if the brideg on your front fork has enough clearance. Of course my tires are not quite the fattys that you got at just 2". Are yours the 2.5s or something even bigger?

 

[Voz]

I did the eMTB update on my Bosch Performance CX and noted that I can no longer change the wheel diameter? Unless I have missed something. I saw a post on here somewhere stating the same issue.

 

[Motodaddy]

That looks totally boss! Those tires look great. Hows the ride? Pros and Cons? What model Cube is that anyway?

My Cube is a Touring Hybrid Exc 500. One suggestion I might offer. I suspect you will find the original fenders not quite wide enough to really keep you dry on a wet road. When I went with the wider tire, I went the extra mile and got wider fenders too. It can make a real difference, if the brideg on your front fork has enough clearance. Of course my tires are not quite the fattys that you got at just 2". Are yours the 2.5s or something even bigger?

View attachment 20556

Thanks Alaskan for the kind comments, your bike looks awesome too, love the colour matched rack . Cube cross hybrid pro Allroad is the model. Yes I had to up the size of the fenders from the original cube 50mm to planet bike cassidia 65mm fenders so that I had full coverage. The tires are 60mm (2.4”) so not quite fatbike but pretty beefy. As far as the trade off goes, I would definitely say that they do not accelerate like the skinny 622-42 tires, they likely won’t be as efficient and I will probably use a higher level of assist to compensate (or get a better workout). That’s ok by me though because the battery will last me to the office and back without issue even in turbo mode if necessary and I feel much safer at speed and cornering with these on and my teeth aren’t rattling anymore. I think bigger tires are a luxury that is made possible by an assist and I think that something like this (or your 2” big bens) are a better match for these bikes. I did keep my original wheel set and I will probably fit some big bens on them. I can probably get better efficiency on the big bens if I’m going on a longer ride but I will stick with the 2.4s for my regular urban riding.

 

[Rune]

... According to my local bike shop the Bosch motor is so finely calibrated by sophisticated German engineers that it will somehow burn itself out if I were to make this change and I would void my warranty. I can understand how a vastly different wheel circumference would throw the speed and range functions off (although 3mm is negligible, in my opinion and is within expected tolerance range of manufacturing, tire pressures etc). I just can’t at all understand how making this wheel swap would affect the Bosch motor in any other way. The only other factors would be torque/rpm and in the real world rider weight, road surface/condition, gravity, etc would introduce way more variation that a motor would have to respond to than a tire swap could introduce. Is my Local Bike Shop mechanic smoking too much or is there something to this??

He obviously doesn’t know what he is talking about. I can choose any circumference between 2336 mm and 2113 on my Bosch Performance Line bike with Nyon display. And regardless of what tire I have on, I chose the lowest number. I live in Europe and the regulations say to turn off the motor at 25km/h, about 15 and a half miles. If your actual circumference is 2113, then you can fool the system to give you assistance up to 27.6 km/h.

 

[Alaskan]

Will at Scooteretti put up the video on Changing wheel circumference setting on the Intuvia display.

I was able to do this on my Nyon with the latest update. Not sure it will still work on the Intuvia now but worth a try.

 

[J0han]

So here’s the finished product with fat 29r fenders added. I’m loving this for the streets of Toronto in spring (also known as construction season). The whole bike no longer rattles going over cracks, potholes and manhole covers.

Bike looks great! I have the exact model and I'm thinking of getting Big Apple 55-622 or 60-622 for mine, as I don't have any 27.5" rims. You didn't have any problem fitting the Super Moto-X tires to the frame at the chain stay? I'm a bit consern that 60 mm might be too close.

 

[Motodaddy]

Bike looks great! I have the exact model and I'm thinking of getting Big Apple 55-622 or 60-622 for mine, as I don't have any 27.5" rims. You didn't have any problem fitting the Super Moto-X tires to the frame at the chain stay? I'm a bit consern that 60 mm might be too close.

Hey Johan,

No issues with the fit of the supermotos on the chain stay. I have about a 6mm on either side. I bought the 27.5 rims off kijiji for 120 so I didn’t feel so bad about buying rims. Having said that I also fitted the 50-622 big bens on the 622 rims and they are awesome as well. I think these are the perfect tires for this bike. I will be using the super moto tires for winter but the big bens are way faster.

 

[Rune]

.......And regardless of what tire I have on, I chose the lowest number. I live in Europe and the regulations say to turn off the motor at 25km/h, about 15 and a half miles. If your actual circumference is 2113, then you can fool the system to give you assistance up to 27.6 km/h.

But I was wrong. It turns out my bike doesn’t give a damn about what circumference I have chosen. It seems like the GPS is the evil mind who turns off the motor assist. BUT the speed on the display differ. When I choose the smallest circumference in settings, I get seemingly higher speeds, and the highest circumference lower speeds. Perhaps my suggested method would work if I somehow could turn off the GPS? I don’t know. But from now on, I will go for the correct circumference to get speed and distance on the Nyon as accurate as possible.