Hi everybody first timer here new to the forum and emtbs

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
Well you appear to be quoting what your bike dealer has told you.
I know there a few dealers out there who don’t have a good word to say about these bikes and yet none of them are able to say what the problem with them is as they’ve never taken one apart.

For the final time, do you have a motor to sell?
 

Smurffire

New Member
May 4, 2021
13
2
Sussex
No I don’t as
Well you appear to be quoting what your bike dealer has told you.
I know there a few dealers out there who don’t have a good word to say about these bikes and yet none of them are able to say what the problem with them is as they’ve never taken one apart.

For the final time, do you have a motor to sell?
no I don’t as they have been warranty sorry
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
There is a very simple reason some people believe rolling the bike backwards is an issue. Unfortunately this is based on a lack of understanding how the motor/drive system works.

Like all ebike drives, there is a reduction between motor speed and pedal speed. In the case of the Flyon it’s 37:1. That means if the motor is spinning at 37 rpm then the pedals rotate at 1rpm.

Given that the Flyon motor has no drive belt but is a strain wave drive system and is engaged permanently what you are doing by rolling the bike backwards is trying to spin the motor at 37 times the speed of the back wheel with the gear ratio of the chain wheel and cassette included.

Ever tried to spin a motor quickly by hand against the force of the magnets?
 

paul-g

Active member
Dec 27, 2019
582
457
yorkshire
There is a very simple reason some people believe rolling the bike backwards is an issue. Unfortunately this is based on a lack of understanding how the motor/drive system works.

Like all ebike drives, there is a reduction between motor speed and pedal speed. In the case of the Flyon it’s 37:1. That means if the motor is spinning at 37 rpm then the pedals rotate at 1rpm.

Given that the Flyon motor has no drive belt but is a strain wave drive system and is engaged permanently what you are doing by rolling the bike backwards is trying to spin the motor at 37 times the speed of the back wheel with the gear ratio of the chain wheel and cassette included.

Ever tried to spin a motor quickly by hand against the force of the magnets?
if the motor spins forward at that speed then whats the problem with it doing the same backwards
with no rider weight load?
i have machinery that through a switch the motors can be reversed at all the speeds of forward drive,
whats the difference?
in the warranty terms (if this shouldn`t be done) should say in 3 foot letters, "Dont push the bike
backwards or you`ll F ck up your Warranty
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
It spins forward easy because the battery is driving it. There isn’t a problem pushing it backwards, I’m just explaining what causes the resistance felt when you do so.
 

paul-g

Active member
Dec 27, 2019
582
457
yorkshire
It spins forward easy because the battery is driving it. There isn’t a problem pushing it backwards, I’m just explaining what causes the resistance felt when you do so.
so taking the battery out would have the same effect pushing forwards as pushing backwards
would you concur?
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
No. What I meant by battery driving it is when the motor is switched on and running.

The point with the Flyon drive is it uses a strain wave unit which is basically an elliptical roller running inside a circular drum and deforming it as it rotates. Google it.

This is what provides the reduction gearing. So when moving the bike backwards you’re spinning the motor and it’s drive unit against the reduction and the loads involved with deforming the drive drum.
Imagine driving along in your car in top gear then put it in first gear and let the clutch out. Huge engine speed relative to wheel speed and massive engine braking.

Also when this occurs the motor is attached to the high speed side of the drive unit so any magnetic forces present are greatly increased due to the rotating speed.
 

Zimmerframe

MUPPET
Subscriber
Jun 12, 2019
14,028
20,817
Brittany, France
No. What I meant by battery driving it is when the motor is switched on and running.

The point with the Flyon drive is it uses a strain wave unit which is basically an elliptical roller running inside a circular drum and deforming it as it rotates. Google it.

This is what provides the reduction gearing. So when moving the bike backwards you’re spinning the motor and it’s drive unit against the reduction and the loads involved with deforming the drive drum.
Imagine driving along in your car in top gear then put it in first gear and let the clutch out. Huge engine speed relative to wheel speed and massive engine braking.

Also when this occurs the motor is attached to the high speed side of the drive unit so any magnetic forces present are greatly increased due to the rotating speed.
That sounds like they could have used that as a charging solution ?

Run out of battery - no problem, push your bike backwards up the next hill and you're back at 10% ! ;) :p
 

Jackware

Fat-tyred Freakazoid
Subscriber
Oct 30, 2018
2,085
2,296
Lancashire
That sounds like they could have used that as a charging solution ?

Run out of battery - no problem, push your bike backwards up the next hill and you're back at 10% ! ;) :p
homer-confused.jpg
 

paul-g

Active member
Dec 27, 2019
582
457
yorkshire
No. What I meant by battery driving it is when the motor is switched on and running.

The point with the Flyon drive is it uses a strain wave unit which is basically an elliptical roller running inside a circular drum and deforming it as it rotates. Google it.

This is what provides the reduction gearing. So when moving the bike backwards you’re spinning the motor and it’s drive unit against the reduction and the loads involved with deforming the drive drum.
Imagine driving along in your car in top gear then put it in first gear and let the clutch out. Huge engine speed relative to wheel speed and massive engine braking.

Also when this occurs the motor is attached to the high speed side of the drive unit so any magnetic forces present are greatly increased due to the rotating speed.
was that a "no" to my question or a side step
 

Sidepod

Active member
Sep 2, 2020
584
395
Oxford
Walking forward is different due to the Sprag clutch (notice your chainweel doesn’t rotate when you back pedal). But to answer your question, no additional stress on the motor going backwards.
 

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