Bosch gen 4

[tony b]

Hi all,
Not been on for a long time.
Just got a new bike with bosch gen 4 motor.
It's a different beast to my gen 3 bike and the gearing is a bit high (too easy).
I know on the gen 3 with small 16 tooth chainring there were 18 and 20 tooth options.
Anyone know if the same goes for gen 4 or is it too early ?
Looking to go maybe 40 from 38 standard as hardly using gears 1-3 and legs like a blurr at 28mph.
Tia.

 

[soundwave]

Kettenblätter / Spider / Verschlussringe - Pro-Cycling-Golla

Kettenblätter / Spider / Verschlussringe - Pro-Cycling-Golla

www.pro-cycling-golla.de

 

[Artstu]

If they're 104 BCD, these too
Gebhardt Singlespeed MTB or Road 3/32" 104mm BCD Chainring - many new sizes now in stock!

VeloSolo Shop - Chainsets, Chainrings, Chainring Bolts

VeloSolo Fixed Wheel & Singlespeed Bike Shop - Chainsets, Chainrings, Chainring Bolts

www.velosolo.co.uk

 

[Fat Rat]

Hi welcome
measure the BCD which is across the chainring bolts centre to centre and go from there
you will find many different options
Also check you have enough clearance between the sprocket and rear chain stays as some bikes are quite tight there when increasing size .

 

[darren66]

Hi all,
Not been on for a long time.
Just got a new bike with bosch gen 4 motor.
It's a different beast to my gen 3 bike and the gearing is a bit high (too easy).
I know on the gen 3 with small 16 tooth chainring there were 18 and 20 tooth options.
Anyone know if the same goes for gen 4 or is it too early ?
Looking to go maybe 40 from 38 standard as hardly using gears 1-3 and legs like a blurr at 28mph.
Tia.

If clearance allows, you'd need to go a lot larger than 2 teeth difference, this would only give approx 1.5mph more for the same cadence, this is why most twin (or triple) chainring cranks have at least 10 teeth difference between chainrings.