first post! electric bike power

[Psycosis]

Here is the bike semi completed.
I need to get a bag or something for the batteries, plus get a bag for the controller.

I have a problem at the moment where the throttle lights thinks the battery is flat, i tested all the connections and the batteries but nothing springs to mind yet why it may be doing this.

Anyone got any ideas please let me know.
I have the batteries connection + to + and - to - and i have wire rated to 30amps, plus a 30amp fuse inline. i get 13.2v from each battery and from the last connector in the link.

I will try it connected in series instead and see how that goes.

 

[monster]

most rear racks have a weight limit of 25Kg but from experience they break at about 15kg. you will only fit 525Wh of SLA on the rear rack and that will only give you 26 miles under optimal conditions. i suspect you will be cutting it fine and will end up pedaling a fair bit.

 

[NRG]

+ to + and - to - is parallel connected, so 13v but double the Ah, I suspect you need to series connect the SLA's...hence your low battery warning light.

Having just moved over to a DIY Lipo pack I can echo the sentiments about SLA's they are not in the same league, the Peukert affect limits the usable Ah and the voltage sags badly under load just when you need it most. Good to experiment with but not a long term solution IMHO.

 

[Psycosis]

Exactly, i want to test first since they only set me back £60 for the 4 batteries, then once i know the system works i will invest in something a bit better. I plan to test the bike once my resister turns up so i don't get the power spikes.

I had a chat with the guy that sold me the kit and he said additing a resister will stop a bike spike that happens when the power comes on.

I need to find some way to hide it all away, and initially i think i will hang a bag from the frame.