How straight forward do you think it will be to add the motor to the rim and spokes?
www.pedelecs.co.uk
Let us know what you decide to do! I can't reiterate enough how much I don't think the battery you have selected will be sufficient (unless you are only planning on going very short distances). The predicted range is never as good as expected in reality.Hi @Collis123 , got be honest, haven't done it for years. I used to find wheel building tough but satisfying.. I'd only do it now if i couldn't buy what i need ready made. In this instance I think I'll do it to use the q70 - and to be sure of a good quality front wheel. In this case the kits on ebay are just too much of an unknown quantity for me. I know there will be much swearing ahead if I get started....
@vfr400 - yup, good point. bag not needed but i think is looks pretty& is also convenient option for carrying the battery about off the bike. That said I am looking at alternative batteries. I share concern about range, so I'm still lookin at that. The rest of it looks okay to me. Im tempted to start hitting the "sod it" buttons and start ordering soon.
That said I just found a thread on this forum of interest. Same idea using a fatter motor:
Wheel Building - Tongxin in Brompton wheel
jerrysimon. Use a pipe cutter on the shaft, use a file first on the shaft to make a small indent so the cutting wheel can sit flush. Good luck MAPMAN.
bmsbattery.com
bmsbattery.com
bmsbattery.com
So, inspired by this thread I've decided to go for a 36v 10AH Hailong battery and the Cute Q70. It won't be as pretty as some but I think will work well enough on the cross bar and shouldn't interfere with folding while also giving me the longer range I'm looking for. @Collis123 I think 48v may be too much for this wee motor & personally I'd be concerned about over heating. My main aim for this is to avoid sweatyness rather than increase speed, so 36v it is. I think you'll find that battery and the ones in the post above yours too big and heavy for a Brompton. Personally, I wouldn't go any higher than 30 cells (1.5kg). 30 cells can get you a good 9Ah, which would take you at least 30 miles of moderately hilly riding without sweating.@TomCC - you've stayed very quiet
I'll let you know how I get on in a few weeks from now...
I concur, small and light suits the Brompton best, in a small removable bag on the luggage bracket. 30 cells would give you 10.5ah with decent cells. Also, now that narrower motors are available I would avoid the options that require stretching the forks.
I tend to disagree. I used the swytch kit for a while and that was about 3.5kg or maybe even 4. As long as you mount it low down by the wheel it will have a low centre of gravity and you won't even feel the extra weight.
My 10ah Swytch kit is 3.5kg but mounts on the handlebars. I find it ok because it’s so much lighter than the Sparticle kit I had previously (about 9kg) which was mounted on the luggage bracket. A heavy weight on or over the front wheel, even if low down noticeably effects handling. 3.5kg isn’t bad but 2kg is better. I wouldn’t want much less than 10ah though.
The Swytch kit just uses standard battery cells and motor. The kit gives an easy solution, but you can get the same yourself. The battery is just a a 20 cell one using 2500mAh cells, like Samsung 25R to give 180Wh. That's enough for about 15 miles with some hills. the larger capacity battery will use 3500 mAh cells. I hope they chose those wisely. The motor shown in their photos is a Q100 (Q70 for narrow forks).
enerprof.de
That pack uses 21700 cells so a lot bigger than 18650s. It's more or less equivalent to a 30 cell 18650 pack.If you are looking for lightweight with decent capacity this might be worth considering in 10S2P format as long as you are not running over 15 amp controller.
Softpack Battery 36V 10Ah BMS 20A XLR-3 with M50 5x4
ENERpower Softpack battery 36V, format 10S2P, square) | 360 Wh | capacity 10 Ah | for Pedelecs, eBikes DIY | LG Chem M50. Important General…
