Pedal Cadence Vs BBS02 output power

[culy30]

My 36v 500w BBS02 has now covered over 1000 miles. I've ridden all kinds of roads and trails and am now happy with my re-programming of the controller as per earlier posts.

My controller is set to limit current not limit speed, hence the motor is free to spin as fast as it can according to the load.

My findings are that the motor likes a relatively fast cadence of 90+rpm. My cadence sensor indicates that my average cadence is between 87-93 rpm depending on how hilly or technical the trail/route. I pedal quite fast compared with some I ride with.

I'm keen to make sure that the motor is operating at as near to maximum efficiency as possible, which should translate into to greater range and battery life. On searching the web I found the attached relating to the BBS02 36V 500W unit. It seems that the motor is wound/geared to produce maximum power under load at 112 +/- 6rpm.

It seems to me that using the bikes gearing efficiently is an important consideration. I currently run a 9 speed 11-34 cassette which is fine for most easier trails and hills under 20% gradient. I do however find that some of the ratios are little too widely spaced and on rare occasions I could do with a higher ratio bottom gear.

Looking at what is available, switching to 10 speed is an option, but I've pretty much decided to go 11 speed 11-40t. Does anyone have any experience of running 11 speed with their BBS02?

 

[appyarry]

My 36v 500w BBS02 has now covered over 1000 miles. I've ridden all kinds of roads and trails and am now happy with my re-programming of the controller as per earlier posts.

I'm keen to make sure tha Does anyone have any experience of running 11 speed with their BBS02?

I have an 11 speed Kalkhoff and although it is not 500w it can go faster than I feel any need to. My cadence is similar to yours. I do like to keep the speed of the motor up and try to use the gears as much as possible though the motor is so good it is easy to be lazy.

I also have a BBS01 on the wife's trike and I'm looking to upgrade that from a 3 speed to a 5 or even 8 speed to make it easier to pedal up steep gradients. Where did you get buy the cable for programming or did you make one?

 

[Kinninvie]

Culy30 what size chainring are you using?
It may be simpler to use a smaller one .
I use a 42T Lekie Bling ring and 11-34 cassette and can pull up anything even though me and the bike weigh over 130Kg between us.
Mine is a 750w but I currently have it programmed to run at 500 watt.

 

[culy30]

Culy30 what size chainring are you using?
It may be simpler to use a smaller one .
I use a 42T Lekie Bling ring and 11-34 cassette and can pull up anything even though me and the bike weigh over 130Kg between us.
Mine is a 750w but I currently have it programmed to run at 500 watt.

Hi Kinninvie, I've already fitted the 42t chainring with 9 speed 11-34t. I find that some of the spacings on the 9 speed cassette are a little wide, hence thinking of moving to 10 or 11 speed. I also occasionally find that on very steep climbs in bottom gear I have to up the PAS to get the cadence back up to a comfortable 80 rpm, but I'm then doing more than 10 mph which is faster than most non-powered riders can manage. (I try not to ride away up hills and I'm also trying to improve my fitness) So I'm thinking maybe a 11-36 10 speed would suit. I'd need to change the shifter, chain and the rear mech though as the pull ratio is different. I need the same components to move to 11 speed, hence the question if anyone has experience of 11 speed with the BBS02 and 42t bling ring.

 

[Kinninvie]

Might be simpler to put your motor onto a ready made 10 or 11 speed bike.
Plenty of people on ES use them without problems and as long as you dont crunch the gears I am sure it will be ok.