Bikes4two

The blue (neutral) and brown (live) colours are those for AC voltages as defined by various regulations since 2006. No such colour coding exists for DC as far as I know. You can see that in cars for instance. Yes, black is normally zero volts and red is the positive. It's interesting to see in some old nomenclature that the red was sometimes referred to as 'live'.

I don't find my legal powered ebikes underpowered at all and in fact I rarely go higher than the ECO assist level. But of course there will always be some that would for many reasons find 1,000 watts insufficient but don't want to buy a motorbike but instead flout the pedelec rules and bring into disrepute those of us that abide by them.

How about going to Screwfix and buying a cheap multimeter - less than £20.

Just to add to the above and not yet mentioned and that I do carry (and have had to use): A tyre boot for splits in tyre walls - a piece of 'metalused' toothpaste tube or similar plus a craft knife blade which when wrapped together sits in the bottom of the puncture repair box - weighs just a few grammes A small first aid kit - mainly plasters, lint and sticky tape. Also a small tube of super glue for small scratches that won't stop bleeding (I've previously been on blood thinners and the glue came in very handy). A 6" length of dowel to get a dropped chain back on Tie wraps have been mentioned but don't forget something to cut them with 2 spare inner tubes (I loath Marathon plus and am happy to deal with the odd puncture) A decent frame pump or similar - those mini pumps can be hard work A part used roll of electricians insulating tape. These and other tools fit into the side pockets on my Carradice saddle bag. Folks may scoff at my toolkit but inevitably on club rides I get asked to help out the unprepared 😏

A nice neat conversion using generic components - love it! By way of inspiration for others, what are the kit components used e.g. motor, battery, controller/display, PAS sensor and whether you bothered with brake switches or a throttle - thanks.

As a general priciple, only connect two (or more) batteries together (aka parallel) if they are (a) of the same nominal voltage e.g. 36v or 48v, and (b) that they are each charged to the same level. All this to prevent a current (as in amps) surge if one battery is at a higher charge state than the other and attempts to bring the low charged battery to an equal state. OR, you look into connecting via dedicated devices to overcome different charge states usually employing electronic trickery like 'ideal diodes' or some such.

That's my thoughts too - as said, I'll bench test it once it arrives to see how practical and reliable such a device is. Indeed so and I have fitted a duel voltage KT controller. In the pic below you can see that the main battery is in a bag under the front handlebars and a 2nd battery/range extender is under the downtube - I have both batteries connected in parallel all of the time (the connection point is inside the metal drinks bottle on the downtube along with the KT controller) Both battery packs use common port charging and I've fitted a common charging connector in the top of the steel bottle. The battery cells are Samsung 35e so not the most energy dense by today's standards but someone gifted me 50 of them in a 10s 5p battery pack and all unused. If I find myself needing more than the 10Ah they give me, it may just be easier to buy some 5Ah 21700 and start afresh. I've done my best to disguise the bits 'n' bobs for no particular reason other than that's 'the look' I like to go for (no ugly Hailong jobbies for me thanks ☹️.) Such a discrete fitting does of course make removing the batteries for charging indoors quite a faff. Like all best projects, it's work in progress 😄.

ps - I'm really not liking this new forum software - no preview of posts, no familiar insertion of codes for quoting, or '@' for users.

Thanks all for your suggestions - much appreciated and food for thought. I was exploring the options and prcticality of this - the light weight mains extension lead might turn out the best way forward 😁 but I may well give the booster linked to a go on a test bench because I'm curious that way. If I was a B&B owner, I think I would far rather let a visitor charge his e-bike with a standard charger than have him cobble together a bunch of batteries with a steaming hot boost converter between them. Fear not @Tony1951 - after a lifetime in electrical engineering I'll not be doing anything outrageous 😉.

Looking ahead to being away in B&B and the battery charging question. Our tandem's 48v battery is fixed to the bike so I'm looking at how I can use my 36v ebike battery packs (which are small and portable) that I can charge in the B&B to take to the bike and charge the 48v battery, or at least, give it a bit of a boost for the next day? Obviously some sort of boost converter but how do you get the CC/CV charging profile? All suggestions welcome - thanks.

You say your rear wheel is 140mm (presumably that's the OLN dimension?) - rear hub motors have a typical OLN of 135mm iirc. As a tandem rider of some 17 years, I find my Magura hydraulic rim brakes brilliant - no faffing with rubbing on discs etc. Their stopping power has been more than adequate and I'm talking about some steep descents on serious hills in France, Switzerland and Germany and fully camping kit loaded too, thus unless you particulalry want disc brakes and the faff of getting braze-on, I'd say to stick with the Magura. For interest, due to having a Rohloff in the rear I have an Aikema AKM100sx in the front wheel (it's actually a wheel from a Swytch bike conversion that someone was selling on) which I'm running at 48v and whilst I no longer tour it's power is adequate for our day rides. As for the issue of front wheel spin on gritty/loose road surfaces, I guess this is a possibilty if using max power and not riding cautiously, but is not something I'm anticipating having a problem with as I generally stick to tarmac.

@ThisWreckage - well, if nothing else you've learnt what Rolloxs you were told about batteries and as regards the Range question, you now know that 'string length' is the big unknown. The best bet is to use that Bosch website thingy to get a ball park battery size. Don't overcook it though as you might end up forking out for some massively expensive and heavy battery that never gets fully used.

You could ring Woosh bikes of Southend to see if they'll sell you a ready built motor - they use the MXUS XF07 in their front wheel kits. Finding a ready built front wheel with motor isn't straight forward not cheap - plenty of rear wheel offerings but not so many front. Getting an AKM SX100 (which is what the Swytch one is) front China is going to cost £130+ (plus Customs duty or not) and then the cost of a wheel build (£100?). Swytch wheels do occasionally come up for sale from disgruntled users (reliability issues, cost of spares, poor CS etc). I waited many months for a 26" one - there seems to more 700c around though.

I had the exact same experience - currently not enjoying the new forum layout one little bit. I found the previous inteface very easy to use and look at. I appreciate that sometimes change is necessary but from the user perspective, this new layout leaves me absolutely cold. However, dear administrators, I really do appreciate your efforts. Cheers, Bikes4two

Such a configuration isn't legally a pedelec so you may not be given the answer you're looking for on this forum as many members do not like to encourage illegal ebike usage.