Swapping Chainrings

Hiswitsend

New Member
Region
United Kingdom
Hi,

Looking at buying an e-bike and after a couple of short rides on a Cannondale with a Bosch motor and an Orbea Vibe I am nearly convinced and have longer test rides planned this weekend.

However am not really struck by the looks of the Cannondale and it's huge motor and really like the Boardman ADV 8.9e, it's just that I could really do with a larger chainring on the front. Fazua tech support said I would need an FSA Spider to change it, has anyone else done this and how easy is it - I've changed drivetrain on a few of my bikes but not able to get a close look at how the chainring is connected on this motor.

Thank
 

PedalUma

Well-Known Member
Region
USA
The key is to find the BCD. You are best off not making a dramatic change in the tooth count and keeping thickness identical.
 

Marci jo

Well-Known Member
If you are still considering the Cannondale here is some info on the Bosch motors. Basically, changing the gears may trigger an error code and shut off the motor. Too bad because Cannondale knows how to make a lighter weight ebike.


I found the thread while thinking of changing the chainring on my Trek class one with Bosch gen 3 motor. Turned out to be not so simple. An owner should be able to change the gears on their own bike without the darn motor shutting off.
 

Hiswitsend

New Member
Region
United Kingdom
That's great info, thanks. I wondered how the motors for away with such small chainrings in some applications, it sounds like it's not driven directly by the pedals.

I'm not so sure what motor to go for, would prefer a mid-drive but I like the look and simplicity of the Fazua. It is a simpler design of motor that can be left at home (ideal for build packing trips where charging it would be a problem)
 

Stefan Mikes

Well-Known Member
Region
Europe
City
Brwinów (PL)
it sounds like it's not driven directly by the pedals.
It's never driven directly by the pedals in mid-drive motors.

Bosch has started using normal size chainrings for Gen 4 motors. Still, you are not allowed to change the chainring size in Bosch motor e-bikes. Fazua is probably easier. No issue with Ebikemotion X35 in Orbea Vibe, as it is the hub-drive motor.
 

Marci jo

Well-Known Member
The best ebike in the world is the one that fits your needs.
Test rides will help narrow the field and also lots of fun.
Of course a pic of your new bike would be great!