Bafang Cranks and Chainrings: 155mm, 160mm and 170mm Fitment for HPC Bikes
Crank arm length and chainring choice are two of the least expensive changes you can make to a Bafang mid-drive bike, and two of the easiest to get wrong. The right part depends on which motor your bike has. This guide sorts Bafang crank arms and chainrings by motor and by HPC bike, using the specifications from our product pages.
Start with the motor
Our bikes use two Bafang mid-drive families, and their cranks are not interchangeable.
- M560 / M600: the Trailblazer lineup.
- M620 Ultra (G510): the Scout, Titan and MPUV, plus the Scout Pro and Titan Pro.
If you are not sure which you have, our Bafang M620 vs M560 comparison explains how the two differ.
Why go shorter than stock
On an e-bike the motor supplies much of the effort, so long cranks are less necessary for leverage. Our 155mm cranks are described as 15mm shorter than stock, which gives more ground clearance and less chance of a pedal strike. We cover the reasoning in more detail in our article on the HPC 155mm CNC cranks.
Crank arms for the M560 / M600 (Trailblazer)
- HPC 155mm CNC Performance Cranks for Bafang M600 / M560: 15mm shorter than stock, stronger and lighter, made from 7075-T6 CNC aluminum.
- Bafang M560 / M600 160mm Powerspline Crankset: lightweight aluminum cranks in a 160mm length, aimed at riders who are getting pedal strikes or riding more aggressively. Listed as compatible with the Trailblazer and Trailblazer Pro, all years.
The Trailblazer frame set page lists 170mm crank arms as the included set, so 160mm and 155mm are both shorter options from there. Choose 160mm if you want a modest reduction, or 155mm if pedal clearance is your main concern.
These are the bikes the M560 / M600 cranks are for:
- Trailblazer, from $6,800
- Trailblazer Pro, from $13,000
Crank arms for the M620 Ultra (Scout, Titan, MPUV)
- HPC 155mm CNC Performance Ultra Drive Cranks for the Scout or Titan: 15mm shorter than stock, stronger and lighter, made from 7075-T6 CNC aluminum.
- Custom 155mm Crankset for Bafang Ultra M620 / G510: OEM-style 155mm arms with standard offset. The page says they are not for fat bikes.
- Bafang M620 / G510 170mm Fat Bike Crankset: OEM 170mm fat bike crankset, listed as compatible with the Titan and Titan Pro, all years.
The fat bike offset matters. The 170mm crankset is the fat-bike part for the Titan lineup, while the 155mm Custom crankset is for standard offset only, so do not use it on a fat bike. The HPC 155mm Ultra Drive cranks are listed for the Scout and Titan.
The M620 cranks are for these bikes:
- Scout and Scout Pro
- Titan and Titan Pro
- MPUV, which runs the Bafang M620 and M630 systems (the product page currently shows a pre-order offer)
Chainrings and spiders
Chainring choice follows the same rule: match the motor and the bike.
- Steel 104 BCD, 38T narrow-wide chainring: heavy-duty steel that the page says withstands loads over 6000W. It is listed as a direct replacement on the Trailblazer, Trailblazer AT and MPUV.
- Lightweight aluminum 104bcd spider: fits Bafang M510, M560, M600, M620 and M630 motors, with cutouts on the inside so you can run a chain guide.
- Ultra M620 / G510 Fat 130BCD spider with 40t chainring: OEM part with extra offset for 4.0 to 5.0 inch tire clearance.
Small parts matter too. The OEM steel chainring nut and the M620 capless steel crank arm bolts are inexpensive replacements. The bolt page lists an M15 x 12 ISIS bolt with pre-applied blue Loctite and a torque specification of 47 to 54 Nm.
Quick fitment summary
- Trailblazer or Trailblazer Pro (M560/M600): 155mm CNC cranks, or 160mm Powerspline cranks.
- Scout or Titan (M620): 155mm HPC Ultra Drive cranks.
- Standard-offset M620 build: 155mm Custom crankset.
- Titan or Titan Pro fat bike (M620): 170mm fat bike crankset.
Before you order, confirm your motor, because an M560/M600 part will not fit an M620. If you are unsure, email us with your bike model and year and we will help you pick the right set.
Comments