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Six part report about my electrified Utopia Kranich with Rohloff gearbox at http://coolmainpress.com/BICYCLINGbuildingpedelec1.html 1: ELECTRIC MOTOR CHOICES FOR A PEDELEC 2: CHOOSING YOUR KIT, AND ITS SUPPLIER 3: HOW I BUILT MY ELECTRIC BIKE IN A COUPLE OF HOURS 4: FITTING THE BATTERY AND CONTROLS 5: CAR STRENGTH LAMPS FOR 36V ELECTRIC BICYCLES 6: SETTING UP CAR STRENGTH LIGHTS ON AN ELECTRIC BIKE http://coolmainpress.com/miscimage/pedelec/220_test_ride.jpg Start at http://coolmainpress.com/BICYCLINGbuildingpedelec1.html

Thanks again, Nealh. That looks like a decision then.

How did your GSM "put paid to them"? Is the battery somehow physically or electrically fragile? I'd like to get several years of life from the battery I choose.

Thank you, gentlemen. Since there is no significant difference in price here, this is starting to sound like a no-brainer. The only thing I can see that the bottom battery has going for it is a more integrated, neater design, totally outweighted by the practical advantages of the top battery. Any more facts or opinions I need before I decide?

Thanks, Trex. I don't mind drilling a hole but I do use the on/off switch on my current battery (a bottle 8.8Ahr job left over from A QSWXK installation) and the USB port on the top one would also be useful. That's two counts for choosing the top one already. Anone else? Anyting else I should know or consider before I put in the order?

Anybody have any experience of or opinions on the choice between these two batteries: http://eclipsebikes.com/images/Samsung.jpg 36V 14.5Ah Lithium Ion Frame Battery 29E Samsung Cells http://eclipsebikes.com/145ah-lithium-frame-battery-samsung-cells-p-1104.html This one has a USB port. £280. http://eclipsebikes.com/images/NewBattery.jpg 36V 14.5Ah Lithium Ion Frame Battery 29E Samsung Cells + 2A Li Ion Charger http://eclipsebikes.com/145ah-lithium-frame-battery-samsung-cells-p-1119.html No USB. £275 Whichever one I choose is for use with a Bafang BBS01 350W centre motor. Experience of either, or opinion about my choice welcomed. Thanks for your help.

Yo, Dave, I also had a good experience shopping at EM3-EV http://em3ev.com in China; I shopped with them for the first time since they had the lefthand throttle in stock and therefore bought the 44T chainring that is Hebie Chainglider compatible from them too.

Thanks, Flecc. Actually, earlier on, back up the thread or in the material that the stupid programmer lost, I said "Bosch-Panasonic".

A chainline of 53.5mm, I think, spot-on. You won't get it closer than that!

Hang on a moment, Bill. If you're fitting a Rohloff gearbox to the installation you describe, with a 73mm bottom bracket, then you want zero (0mm) in spacers. In fact, you will have 2mm too far in spacers. I don't think it will matter all that much, and you can't do anything about it anyway, but you don't want to aggravate the distance by adding to it unnecessarily.

I have a couple of low-mileage worn-out Shimano boxes, so I had to decide between proper German engineering that lasts forever (and comes with what is effectively a lifetime guarantee) and buying five or six Shimano and being left with nothing. It was a no-brainer, helped along at that time by moving into a house my wife liked on the steepest hill in a town called the "Rome of Ireland". Perhaps you're happy to put so much power through a Shimano box that I wrecked with nothing more than my legs to power it, because you have a gentler touch. We'll see in a few years whether your optimism is justified. I hope you're right, because a Rohloff is outrageously expensive. Actually, Bafang at first tried to pretend that the rotation counter was a torque sensor of some magical kind. The point I'm making by "pseudo" is that only the Bosch item (and a not-very-common aftermarket item available from China) is atrue torque sensor, and none of the pretenders, including Bafang's, whatever they call it now, is real. Your Bosch is a Big Brother Machine, BAK48. It doesn't work for you, it works for the German government. It measures carefully how much torque you provide by leg power, and adds precisely the same, not an iota more, because the German mindset is that whatever isn't permitted is streng verboten. By contrast, the Chinese probably have an Italian consultant who noticed how loosely the EU wrote the most recent peddle total power spec (basically it is what the manufacturer says it is, which is a good reason to buy Bafang, because they make very modest power claims!), and very likely decided they could also try it on with the ratio between user power-input and what the motor provides. I'm not going to complain! Are you?

Whenever you're ready, Bill, just ask.

Bill, I answered these questions at Rohloff Speed 14 hub gearbox with Bafang BBS mid-motor and there's some opinion at Rohloff Speed 14 hub gearbox with Bafang BBS mid-motor: installation and use

The next problem is the tooth count of the chainring. The motor is wide, so the chainring is dished to fit over it and give a tread (the trendies and poseurs call it the "Q factor" so they can express surprise when you don't know what it is -- it's the width over the outside faces of the cranks where the pedals screw in) within reason; roadies like the tread to be as narrow as possible The dishing, with the size of the motor, limits the tooth count. The smallest chainring from Bafang, last I heard, is 44T. Smallest available in the aftermarket, last time I looked, was 42T, pricey but beautiful, carved from solid aluminium in Italy. If you like the 38x16 Rohloff gearing that a lot of tourers have followed me into, tough. I like steel chainrings, so I fitted Bafang's own 44T dished ring, for two further reasons, one already described above: it's an easy fit and fix for a hyper-correct Rohloff chainline. The other reason is more esoteric. Because I ride in street clothes and don't like trousers clips, and have anyway developed a near zero-maintenance bike, I use a Hebie Chainglider on my everyday bike. The Chainglider must use the special Rohloff rear end, and the Chainglider front ends that work with the Rohloff rear end are limited in tooth counts, coinciding with the Bafang tooth counts only at 44. So I could fit that one or go custom... Maybe later I will have a custom ring machined out of stainless, because I had good experience with the 38T Surly stainless ring, maybe I'll stick with the Bafang pressed steel chainring. We'll see. The point is, the Bafang 44T got me going almost instantly, without waiting for custom work. Nor did it, with the torque of the motor, seem a hard choice after being accustomed to the soft option of 38x16; motor just filled in. And, of course, with 14 evenly-spaced gears in the Rolloff, it wasn't ever going to be as big a problem as at first I feared. Wonderful what we discover with 20-20% hindsight. Before the Chainglider-compaitble chainring arrived from China, I tried riding in street clothes without chain pretection. I didn't get very far before my trousers were twice caught up in the chainring and chain. I gave it up as recipe for broken bones.

This: http://coolmainpress.com/ajwriting/wp-content/uploads/2015/09/andre_jute_bombing_downhill_at_kilbrogan_12_sept_2015_800pxh-573x510.jpg Bombing down the hill at Kilbrogan The idiot software of this board just lost my complete description of the installation and use of a Bafang BBS midmotor with a Rohloff hub gearbox because it claimed it was over 10K words. What sort of a motherless programmer writes a deadend loss like that with no return path? I don't have time to rewrite all of that for five people to read, Bill, so I'll just answer your specific questions and in future place my complete review someplace safer. *** Bill "need(s) info re alternate chainrings/chainline etc" The Rohloff chainline demanded by Bernd Rohloff is within 1mm of 54mm, measured from the centreline of the hub (on a well-built from from the centreline of the seat tube!) to the longitundinal centreline of the teeth on the chainring, i.e. to the middle of a roller on the chain if it doesn't fit too loosely. The offset of a standard dished chaingring for the Bafang BBS mid-motor is 51mm. I used 3.5mm total of spacers, as 2.5mm and 1mm, mainly because I already had them and they were already painted bike color, between the bottom bracket shell and the rear ride of the motor supposed to rest on the bottom bracket shell's rim. This moved the chainline to within 0.5mm of the desired chainline. Practical measurement is from the far (non-driveside) of the seat tube to the centre of the thickness of the teeth, minus half the diameter of the seat tube. Spacers you can buy from Chainreactioncycles.com, which is where I got mine, as either dedicated bottom bracket spacers or, if you can determine that they have the same inner and outer diameter as your bottom bracket shell, as cheaper and often generic sprocket spacers. I don't know what "etc" is. If you have a specific question, ask here and I'll try to answer. Good luck with your build, Bill.