!!!!! HELP me with my 26" Bafang Rear Wheel Build please !!!!!

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Cheers Alex, i can fit the socket to the bag by placing a sheet of metal/plastic inside, going pack out with foam etc so it will be virtually a rigid bag.

I would be looking to fit it vertical side of the triangle bag at the top right corner.

How secure are those plugs ? Do you expect to lose many, seen some nice waterproof alu type that are threaded and have a threaded cap cover/chain, but prob be a pain over time.

PM your address and i'll post out charger to you.
 
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103Alex1

Esteemed Pedelecer
Sep 29, 2012
2,228
67
Cheers Alex, i can fit the socket to the bag by placing a sheet of metal/plastic inside, going pack out with foam etc so it will be virtually a rigid bag.

I would be looking to fit it vertical side of the triangle bag at the top right corner.

How secure are those plugs ? Do you expect to lose many, seen some nice waterproof alu type that are threaded and have a threaded cap cover/chain, but prob be a pain over time.
That makes sense. The plugs are a tight enough fit not to come out when riding and push in over the female socket - you can also fit one of these which has a backing gasket behind the socket if the socket's screwed in tight but also just a push fit :

Neutrik SCDF Rubber Sealing Cover from Sound Exposure - The leading Pro Audio and Broadcast Superstore

I have one actually - forgot about it - may pop it on to try in use, but seem to remember the dummy plug is a better fit inside the socket. None of these things are without their faults !

Screw cap with chain won't get lost (especially if you're charging away from home) so that's sensible - it's just an aesthetic thing really as to what's the best compromise of looks vs function for your particular setup.

I looked at these actually along the way (3-pole 7A using 2 contacts so as no chance of coupling back to front and wrecking the battery ! ) :

CONNECTORS - Self Strip, Multipole, Battery Terminals, Blue Sea, Junc Boxes, Commoning Bars, Dashoard, Waterpfoof, Shaver, Plugs & Sockets Power & 12v - Waterproof plugs & sockets - Canal boat Electrics - chandlery - narrowboat spares

PM your address and i'll post out charger to you.
PM'd. Many thanks.
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Well i'm finally up and running, only done little trips so far of less than 2 miles but all seems good :)

I understand the battery has a BMS and the controller for undervoltage but what voltage do i need to be monitoring on my el cheapo voltmeter so i know when to re-charge.

Cheers guys, will get some pics up when i get chance.
 
D

Deleted member 4366

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Everything should be automatic. 20aH will get you a long way. I've never managed to get my battery down far enough, but once you get down to about 35v, it'll go down rapidly and cut-off probably in a couple of miles depending how much power you use. Charge your battery whenever convenient, don't try and run it right down.
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Cheers Dave, so it does not matter if i give it a small charge ?

I do not need to leave it charge fully each time i charge ??
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Thought everything was going to smoothly !!!

The Blue/Yellow brake input is not working ? Not checked since i had my little 'accident'.

Shorting them directly at plug on controller but motor still spinning !!!

How can i check this ? Can i look for voltage ?? Or is it open up the controller ???

EDIT - I think i may have removed power to it whilst removing redundant/spare cables from controller.
 
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D

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Both myself and Saneagle have the same battery as you. We charge after every ride, but I probably wouldn't both for less than 5 miles unless I knew my next ride was going to be a long one.
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
There's a thin red wire that goes alongside the thick red and black wires from the controller to the three-way power connector. That wire has to be connected to the battery +ve for the controller to give power, so it works as a "standby" control if you put a switch on it. The controller still takes a small current when on standby, so don't use it as a permanent on/off switch or else you'll brick your lipos.

The easiest solution for the brakes is to swap the rear caliper for a cable one. I think Juicybike sell hydraulic brakes with switches as a spare part at about £100 each. You only need a switch on the back brake as a minimum.

The "hidden wire" brake sensors are a bit of a mystery. They're sealed so you can't see what's inside. All I can say is that you pass the cable through them, and they work perfectly.


For a main isolate switch, you could have a go at making one of these. You can buy the FETs from Ebay relatively cheaply, and the rest you can get from Maplin. You don't need a pcb. You can drill a piece of thin plywood and hard-wire the components on the back, or use a bit of Veroboard from Maplin.


Going to make one of these next. Got the brake working :)

Is it just switching the 0v across the controller/battery ?

What sort of gauge wires are required for the three wires coming from switch ??
 

103Alex1

Esteemed Pedelecer
Sep 29, 2012
2,228
67
Going to make one of these next. Got the brake working :)

Is it just switching the 0v across the controller/battery ?

What sort of gauge wires are required for the three wires coming from switch ??
You won't regret it and glad you've got the build back on track :). I don't actually understand how it works or why the MOSFETs are used but really makes sense not to be unplugging controller from battery every time you put the bike away and sparking it every time you reconnect.

Re: the gauge wires - if you use a toggle/push button switch with it the wires to/from the toggle don't have to be very thick - we used 6A rated equipment wire on mine.

The main +ve/0V wires are part of the main feed between battery/controller. I used 12AWG silicone wire on mine across the switch
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Cheers Alex.

Spent ALL day yesterday out on the bike ans was very impressed, done around 12 miles and meter dropped about 1v !! That is with virtually no pedal assist, i loved getting home and hitting a steep hill i usually dread, i was actually going into faster gears and flew up there. :)

Need a set of mudguards now, are these any good ?

Wiggle | SKS Bluemels MTB Mudguard Set | Mudguards

Bear in mind i have front suspension and rear pannier (do not want seatpost type) plus 26" x 2" tyres.

Cheers
 
D

Deleted member 4366

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http://www.chainreactioncycles.com/Models.aspx?ModelID=34474&_$ja=tsid:46412|cgn:Mudguards|cn:Chain+Reaction-UK-PLA-PLA-Eng-DT-SE|kw:116763UK_Beavertail+Mudguard+XL+Set&gclid=COn-ltrL8rcCFbMdtAodsToA9Q

They fit on full suspension bikes too. That's a Kraken behind modelling them for you.

 

103Alex1

Esteemed Pedelecer
Sep 29, 2012
2,228
67
I think that link above is for these XL Beavertail ones :

SKS Beavertail Mudguard XL Set | Buy Online | ChainReactionCycles.com

I actually fitted the regular ones which work OK on my bike with 2.1 tyres but the clearance is very tight so if above have been tested on the Kraken then they'd be the ones to go for.

Glad you finally got out riding :) .. have you tested the bike on full throttle yet ? ;)
 
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bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Cheers Guys, ordered.

Yes Alex, full throttle most of the time !!! Getting just around 20mph with no assist (this is an estimate as i have not set my Cateye up for 26" wheel).

When riding yesterday i lent y mate my Felt Road bike which is VERY light and he could not keep up with me.

The problem is now i have three mates who want to build one plus my mother wants a small front drive system...lol

I want something faster for dedicated offroad now, so will be selling my Spesh Epic FSR Carbon Comp to fund it.

Cheers guys :cool:
 
D

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Did you join the green and black wires on your three speed switch connector?
 

bilabonic

Esteemed Pedelecer
Feb 20, 2013
294
6
Been having a little read on here and came across a thread off adding a 'Booster' battery, i think this would could fit my needs of more top end speed.

I have battery monitors, charger (6cell though), plenty of cable, and could simply fit in in my rear pannier with controller with minimum cable run.

I would prefer just to buy a 6 cell pre made battery from somewhere but i doubt this would be possible.

Anyone advise ?

Cheers