Want to know how many miles or km's your Bosch motor should last?

[Bearing Man]

I thought anyone running a Bosch motor may find this interesting? I have loaded this as a pdf because there are several large photographs showing wear and tear shots from a Bosch Performance Line motor after 20,000 kilometres. What we found was fairly definitive proof of how far one of these motors will go before it's completely shot and in dire need of a complete overhaul.

 

[Ocsid]

Am I right in assuming this is a motor used at EU legal ratings?
If so, have you a "view" on how derestricting it would alter your 10K + mies prediction?

 

[Fat Rat]

Good read

 

[soundwave]

Am I right in assuming this is a motor used at EU legal ratings?
If so, have you a "view" on how derestricting it would alter your 10K + mies prediction?

imo im not far of half that distance with my 2014 haibike and dongle.

and no problems so far

 

[Bearing Man]

Am I right in assuming this is a motor used at EU legal ratings?
If so, have you a "view" on how derestricting it would alter your 10K + mies prediction?

Technically, having a dongle should make no difference what so ever. You are not tuning or putting more force through the motor you are only making things turn a little faster for, generally, short periods of time. The Bosch motor is sold to many countries, de-restricted. It is designed to run in it's normal mode and only restricted by the laws of some countries. So, no, it shouldn't make any difference.

 

[Ocsid]

Thank you Bearing Man.
I have to say you surprise me with your belief there will be "no more force through the motor" at speeds above the EU speed limit. But I accept the motors are offered in higher than EU speed markets, so no doubt they are designed for that, however probably at some impact.
I have no issue with the fact the rotational speed increases but the power for higher speeds is not a linear relationship as would be the case if force remained unchanged. Drag alone is a V squared law so the torque [ force] must increase, and significantly?

 

[soundwave]

the faster you go the less the motor assists tho it still draws max power but after 30mph and 120rpm at the cranks its the wind that slows you down.

sclass motors are the same bar the speed limit for those are 28mph.

 

[Bearing Man]

Thank you Bearing Man.
I have to say you surprise me with your belief there will be "no more force through the motor" at speeds above the EU speed limit. But I accept the motors are offered in higher than EU speed markets, so no doubt they are designed for that, however probably at some impact.
I have no issue with the fact the rotational speed increases but the power for higher speeds is not a linear relationship as would be the case if force remained unchanged. Drag alone is a V squared law so the torque [ force] must increase, and significantly?

I understand your thinking but lets say you have a Bosch CX, it can only ever give you 300% of assistance, whether you are traveling at 15mph or 30mph, all the extra power is being supplied by you. In fact, there is an argument here that a dongle could save wear and tear because to exceed 15mph on a restricted bike, you are the one who must add more power and therefore more stress on the components

 

[soundwave]

300w lol you get more than that same as if under the 15mph limit and climbing the motor can use full power as eddie has nuked a 500w batt in ten miles going up a mountain.

cant put a watt meter on a bosch bike but the yamaha motors can use 800w+ but either way the batt suffers as max range i can get is about 25 miles if i floor it and even less if there are any climbs.

 

[soundwave]

 

[Bearing Man]

300w lol you get more than that same as if under the 15mph limit and climbing the motor can use full power as eddie has nuked a 500w batt in ten miles going up a mountain.

cant put a watt meter on a bosch bike but the yamaha motors can use 800w+ but either way the batt suffers as max range i can get is about 25 miles if i floor it and even less if there are any climbs.

Should have said 300% just changed it

 

[Ocsid]

Thanks, so derestricting does not alter the power used.
Therefore, it will follow that as the power consumption is the same but the bike is going faster the range you achieve from an xWatts battery increases proportionally with the speed increase; you doing all that extra speed related work not the motor.

Certainly different to how I thought things would go, but interesting to learn. I had thought derestricting a bike would clip the range not significantly increase it, shows how assumptions can be wrong. Thanks.

 

[Bearing Man]

Thanks, so derestricting does not alter the power used.
Therefore, it will follow that as the power consumption is the same but the bike is going faster the range you achieve from an xWatts battery increases proportionally with the speed increase; you doing all that extra speed related work not the motor.

Certainly different to how I thought things would go, but interesting to learn. I had thought derestricting a bike would clip the range not significantly increase it, shows how assumptions can be wrong. Thanks.

You are mistaking electrical power with torque, you will use more battery because you are still being assisted past 15mph but the motor is not putting more stress through the components.

 

[soundwave]

when you remove the speed limit its the modes and the amount of effort you put in as to how far range wise you will get.

so in turbo with max 120rpm and the right gearing and wind behind you can hit 40mph.

but in eco even at the same rpm it is going to take alot more effort but save lots on the batts range.

 

[Danidl]

You are mistaking electrical power with torque, you will use more battery because you are still being assisted past 15mph but the motor is not putting more stress through the components.

I suspect your sophistry is getting you confused.. . Every rotation of the motor and it's reduction gears causes wear and tear . High speed motor running means more wear. If you are unfortunate to put the motor into an inappropriate gear, where it does not have the torque to rotate at full speed , there there even more heat damage and mechanical wear in the teeth. Removing the speed regulation allows the motor rotate faster and for longer so the wear is more intense. Sorry but no free lunches!. It is only when you exceed the maximum assist speed of the motor that it ceases to wear. .. Blame it all on Newton and action, reaction

 

[Deno]

Great info BM! This post should be a sticky.

I have 11k km's on mine in a year, dongled and spends most of its time above 25kph, still works fine. If it lasts long enough to get me home today and needs a rebuild by your good self I will consider that money well spent considering the bike has replaced my car.

 

[Ballynoes]

Excellent post just the kind of info we all need... Thanks.

 

[Bearing Man]

I suspect your sophistry is getting you confused.. . Every rotation of the motor and it's reduction gears causes wear and tear . High speed motor running means more wear. If you are unfortunate to put the motor into an inappropriate gear, where it does not have the torque to rotate at full speed , there there even more heat damage and mechanical wear in the teeth. Removing the speed regulation allows the motor rotate faster and for longer so the wear is more intense. Sorry but no free lunches!. It is only when you exceed the maximum assist speed of the motor that it ceases to wear. .. Blame it all on Newton and action, reaction

I think you have answered your own question in your post. My argument was: When de-restricted, you only use higher motor speed (over 15mph for relatively short periods of time, in relation to the amount of time spent above 15mph, so although there would be wear, it would be relative. If you don't have a de-restrictor, you are continually hitting the limit and therefore having to put extra power through the crank manually (the same as being in an inappropriate gear).
Personally, I don't know if either scenario would ever make any noticeable difference, it was more an observation?

 

[anotherkiwi]

Surely if you get to your destination faster you spend less time running the motor? Hence less wear and tear.

 

[Bearing Man]

Surely if you get to your destination faster you spend less time running the motor? Hence less wear and tear.

Is that not like saying, if you drive faster in your car you'll get there quicker and therefore use less fuel!?
As Danidl said, no such thing as a free ride.