The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

The New Hotness

  • Tour Easy: Bafang BBS02 Lower Power

    It turns out Mary rarely used assist level 6 and had no use for levels 7 and 8 of my derated BBS02 configuration:

    LC=15
    ALC0=0
    ALC1=5
    ALC2=7
    ALC3=16
    ALC4=25
    ALC5=37
    ALC6=51
    ALC7=67
    ALC8=85
    ALC9=100
    

    Level 9 must be 100% of the maximum motor current so the throttle can apply full power to get out of the way in a hurry.

    The new and even more derated configuration allows small-step assist level selection for our usual riding, at the cost of an unused huge step to level 9 for the throttle:

    [Basic]
    LBP=42
    LC=18
    ALC0=0
    ALC1=4
    ALC2=6
    ALC3=9
    ALC4=15
    ALC5=20
    ALC6=25
    ALC7=30
    ALC8=40
    ALC9=100
    ALBP0=0
    ALBP1=100
    ALBP2=100
    ALBP3=100
    ALBP4=100
    ALBP5=100
    ALBP6=100
    ALBP7=100
    ALBP8=100
    ALBP9=100
    WD=12
    SMM=0
    SMS=1
    [Pedal Assist]
    PT=3
    DA=0
    SL=0
    SSM=4
    WM=0
    SC=20
    SDN=4
    TS=15
    CD=8
    SD=5
    KC=100
    [Throttle Handle]
    SV=11
    EV=42
    MODE=1
    DA=10
    SL=0
    SC=5
    

    The LC=18 line limits the maximum motor current to 18 A, rather than the rated 24 A, which may improve controller MOSFET longevity; reliable evidence is hard to come by. Controller failures seem to happen more often to riders who value jackrabbit acceleration on harsh terrain, so it may make little difference for road cyclists.

    So level 5 now selects 75% × 20% = 15% of the motor’s nominal 750 W:

    Tour Easy Bafang - display 26 mi
    Tour Easy Bafang – display 26 mi

    Call it 115 W: we’re both getting plenty of exercise!