MobyRick

MobyRick submitted a new listing: [plain]Rockrider battery wanted: For E-ST 100/500/900[/plain] Learn more about this listing...

Fantastic, thank you! I'll check the wiring.

Just to add, when it's fully loaded, the bike will need to be in sport or boost most of the time because of the weight. So it definitely wouldn't make 25 miles without a second battery.

Thanks for the info! The battery (and bike) is only a year old but yes I'm in the high power modes a lot, and I've been out on some cold days. I was surprised though. I need to sort it out because I'll be carrying full panniers on a trip soon. Nothing too ambitious, I just need to be sure it will do 25 miles while carrying some weight. Getting stranded doesn't bear thinking about!

Thank you! That's exactly what I'm aiming for. It's good to hear some positive confirmation. Cheers

Thank you! That's really useful. I was always going to charge the batteries separately. I'll have to look into what you said about batteries having similar capacity, thanks for the tip. My main battery is 14Ah but the second battery will probably be 10Ah. Sounds like mounting on the rack could be easier than I thought. I'll look into that too!

You've certainly proved what a clever chap you are, and how adept you are at missing the point and contributing useless information. Well done.

Yes the blender/diode should handle differences in charge and blends discharge so both batteries drain at the same rate. I was just wondering if anyone had done a similar DIY solution.

Thanks for your reply. I'd need the extra range pretty often. My bike has been discontinued so I may not find replacement batteries now. I'd rather not have to carry a full-sized second battery anyway. Yes the blender unit or Obviously I meant discharge, but thanks anyway for your lack of help.

Hi all. I'm new here. I've got a Rockrider EST900 and I want to fit a range extender battery that is ideally quite cheap, simple to fit, removable and not too big or heavy. I live in Northumberland and when I'm out in the hills I don't get much more than 20 miles. I've only come across a couple that might fit the bill: Woosh bag battery 36V 10AH - https://wooshbikes.co.uk/?batteries - I could either fit this to the seatpost or strap it to the rack. UPP bottle battery 36V 7AH - https://www.unitpackpower.com/product/s001-2-36v-7ah-bms20a-samsung-lg3500mah-cells-battery/ - This is the only one I've found that is small enough to fit on the frame (It's a small bike with a big battery) Alternatively I could fit a second battery to the rack. I would have to strap it on somehow because it needs to be removable. I can access the wires in the motor and I'm happy to do a bit of soldering. I know I'll need to fit a balancer/ideal diode so both batteries discharge in parallel. But I haven't done this before and I don't want to give the impression that I know what I'm doing! I was just wondering if any of you guys have added budget range extenders like this, or if you have any advice or thoughts? Thank you!