No announcement yet.

BBSHD cuts-off over 1000W

  • Filter
  • Time
  • Show
Clear All
new posts

    BBSHD cuts-off over 1000W

    Hello -- I'm riding a Luna Cycle Roam Fusion with a BBSHD Ludicrous. Battery is 52V / 28ah. I've had some issues over the past months with premature cutoffs of the engine, which I've diagnosed to these behaviors:
    • The BBSHD engine will cut-off if the output exceeds 1000Ws. This will occur independent of the battery charge level. This will occur independent of engine temperature. This will occur independent of bike speed. A number of factors can trigger this, including: change of elevation, change of terrain, pedaling while cornering in a high gear or even blustering a stiff headwind!
    • The display stays powered on through this cut off. It is only the engine that powers down. Throttle cuts off as well.
    • To remedy this, I briefly cycle the bike's power. At times when I cycle power as I'm riding, I'll get a Failure 08 code flash momentarily, but then returning to the default display. Engine will briefly rev upon start up, as normal.
    I had possibly thought it was a LVC on the controller, but that would have shut off the bike's power, not just cut the engine. It would have also been slightly dependent on battery charge. Instead, perhaps a LVC on the BMS? Would that shut off the system as well, versus just killing the engine?

    Perhaps a faulty connector on one of the 18650s that, under load, shorts out? Would that cut the engine, but keep the power to the system? Perhaps just a borken display?

    Any thoughts?
    Last edited by ncawthon; 10-08-2018, 10:02 AM.

    LVC in the BBS controller only shuts off power to the motor - display stays on etc. BMS LVC cuts everything. The only way I know I've hit the BBS LVC (besides looking at the voltage) is that I'll feel the power cut when pulling enough current to hit it on a low battery.

    What is the LVC setting in your BBSHD? What is the maximum current set to?

    Error 08 is the hall sensor but odd that it would behave the way you describe...


      Thank you AZguy -- that narrows it down to now just the BBS controller. I don't know the LVC setting currently (pardon the pun) What would you recommend for both the LVC and Max Current with a 52V / 28ah BBSHD?

      The Error 08 is weird, I agree -- luckily, it is just a blink.

      My daily usage is a pretty rough scenario -- I commute 25 miles twice a day, charging at work in-between. Thus, a need for speed.



      • AZguy
        AZguy commented
        Editing a comment
        Since I run both 48V and 52V batteries I have it set a bit too low for 52 [and a bit high for 48) but just watch the voltage anyway and try not to hit it with either but sweat it zero if I hit it with the 48V. 44 or even 45 might be more reasonable fro a 52V and not trying to run them to zero. They are dropping voltage and sagging so much by ten there's no good reason in my mind to run them that low but then again I can carry to batteries mounted so I generally have a reserve which admittedly changes my perception...

      Good to know for the BBSHD. I would want to do the same with the BMS as well, no?

      Originally posted by Rodney64 View Post
      You can lower this to 38 volt with the program cable