So, i reckon your motor rpm was about 245 @20mph. Do you know what rpm the code 12 is supposed to be?
I think the BMS states the size of the BPM as 137mm which is 2mm longer than the 135mm. Can this be the reason?Evening All,
Been monkeying about on my BPM Build this afternoon. Anyway its virtually complete now.
Issues I had fitting the kit :-
- Correct spacing as the 7 speed cassette was slightly longer than the spacers given. This resulted in my pulling the frame a bit to get it all in without binding.
Just over 28amps with 1300w showing on the meter at 47v. Great fun, but a lot more power than I wanted. I'll post some picures of the batteries tomorrow, when I get my camera sorted.Nice set up, especially the doner bike (£15 quid!!!).
How much power are you drawing at 25mph? Any pictures of the batteries?
Thanks. I haven't weighed it yet, but it's definitely lighter than my Sunlova, which is 29kg. Should have a range of about 10 miles, or maybe 20 with my other battery as well - not quite enough to tow my trailer to Presteign. I'll have to think again!1300watt, must be a right little beast. Mines only hitting half of that and i already think thats loads or enough for a bike.
Guys on es that run 2500 peak out of the bikes must be like motor bikes but more scarey! Most motor bikes weigh in at 120kg+
If anything its made of appriciate the speed of a push bike and hitting past 25mph really is a scary prospect.
Glad your build went well D8veh!
Can anyone give a heads up if there is the same issue with the rear hub BPM pleaseAlso, there is a very large space on the disc side which needs packing out for the drop-out to butt up against.
No, the measurement is exactly 137mm between the drop-outs. The problem is that the ant-rotation washer doesn't reach the shoulder it should sit on on the free-wheel side, so you need a couple of 10mm washers drilled out to 12mm to fit inside the free-wheelCan anyone give a heads up if there is the same issue with the rear hub BPM please
I think the anti-rotation washers are supposed to fit in the inside of the drop-outs. I can't see one in your picture, With them in, the gap will be about 6mm less. The rest (if there is any) will pull in when you do up the nuts.Finally got some more time to work on the build after a hectic family-orientated Easter.
I have the motor mounted. I found a couple of issues; the first was that the drop outs needed a very small amount of filing to allow the axle to drop in.
Also, there is a very large space on the disc side which needs packing out for the drop-out to butt up against.
Really the axle could do with protruding a little more on this side as by the time the washers and bolts are on there isn't enough space left to fit a torque arm. In contrast, the other side has more than enough space...