warmrain

I have lithium cells in my laptop more than 11yr old which are working just fine albeit the wattHour capacity has declined.

I don't know the specifications of the Yamaha bike but the battery is not the main problem as it is clearly capable of powering the current motor (albeit total capacity might have reduced). I suspect the maximum torque from the motor is low and inadequate, especially on this old model of e-bike and hence the problem with hills. The point about not adding more weight is also relevant as it may not give you the best weight-vs-performance ratio. I am sorry to hear of your health problems, but you might be better off selling off your old bike to someone who lives in a flat city/town and use the proceeds to supplement purchase of a new bike with motor capable of delivering at least 85nM max torque? [With a good range of gears.]

Hi mm1, I notice that CambridgeCycleCo.co.uk has stock of 1x Gazelle Orange C7+ Low Step-thru with XS frame size of 46cm at £2199. Need to get in quick if interested as they seem to be out of stock in everything else.

You are welcome. Let us know how you get on.

Hello mm1, the shop I'm thinking of is in Navenby village just south of Lincoln and is called PedalElectricCycles. Need to phone first [01522-255760] to fix an appt because of Covid, and also best to enquire whether he has the specific model(s) you are hoping to try available in the shop. He has a few more in a warehouse which he could bring round to the shop but stock may have diminished somewhat because I have just bought one off him . Navenby has a nice sharp hill just yards from the shop and some quiet backroads behind -- so good location to test out the bikes.

Gazelle are still selling in the UK and if you type "gazelle bikes cambridge" into Google you will see 3 dealers come up near you. I believe their models 'Ami', 'Paris', 'Orange' and 'Grenoble' all come with an option of step thru in XS (extra-small) size - 44cm frame - 'suitable for person height of 1.55-1.65m' so should suit you. The first is a Shimano crank drive and the latter three Bosch. I have a very helpful Gazelle dealer near me in Lincolnshire who has lots of Gazelles to try, but that might be too far away for you(?).

Hello, look at this thread. http://www.pedelecs.co.uk/forum/threads/kalkhoff-panasonic-charger.32259/ Good luck.

I see that the subject of this discussion was/is "Cheating". Not how an electric bike should be described or what legal terminology is adopted by relevant authorities. "Cheating" is something purely intrinsic to, and in the mind of he/she who says 'it is cheating'. It arises because either (a) they feel they are in competition, or (b) they feel there is something they are entitled to which they don't have access. The traffic light dragster who feels you are cheating because your stock looking Ford Fiesta has a modified supercharged engine and you outdrag him in his *really* stock Ford Fiesta has a self made problem because he has set himself up in competition with you ... and also feels he should be entitled to a supercharged motor as well. ....(a), and (b). The person who feels rich heiresses are "cheating"/ "have cheated" because they-just-happened-to-be-the-daughter of a rich family and didn't work for it are agonising because of their indignant sense of entitlement ... and also setting themselves in comparison & competition. Even though objectively they themselves may be both healthy and and have enough to eat/live without hardship. [Marxists may beg to differ]. The person who invented the aeroplane wasn't "cheating". He was just solving a technical problem. When electric bikes are (almost) the same price as non-electric bikes, there will be no chance for a sense of witheld entitlement and it will be simply an engineering advance that gives you a choice of having more exercise or less exercise. Those who still mistakenly feel that the world is competing against them will turn their attention to having a snazzier paint job on 'their superior' electric bike. It is a technical / engineering advance which can also sometimes solve a human medical problem. 'Cheating' is simply a problem within the own psyche of he who calls out "you cheat!" at the moment. Don't worry about it.

Thanks for the suggestion. I guess its a trade off whether to lug it along as my new battery is substantially larger capacity wise and should cover most circumstances - if it lives up to its stated capacity rating ... delivered from Germany but in small print says 'Made in China'. Some good stuff is made in China -- all those hub motors used by various UK bike manufacturers are made in China I believe. I couldn't bring myself to pay £600+ to 50Cycles, and this is less than half of that.

OK, an update. SUCCESS !! I have managed to get my charger working! Some details of voltage testing of the charger WITHOUT being connected to the battery: After rest overnight without being plugged in -- zero volts across any pair of terminals. On plugging into the mains, intially zero, then after a few seconds I hear a very very faint click followed by a jump up in voltages across some terminals BUT in REVERSE polarity (of expected). Between B & E = 10.9v with 'E' positive. Between D & E = 12.3v with 'E' positive. Between B & D (the main charger output pins for battery) = 0 v. On then unplugging the charger from mains, both these voltages decay slowly over several hours. [This suggests to me they are residual voltages on some sort of internal capacitor.] I then opened up the charger. Rather fiddly job as it is held together by 'security Torx' screws which have a raised 'pip' in the centre. I needed to go source a corresponding 'security Torx' screwdriver (of T10 size) which has a hole in the centre of the business tip. I then lifted out the charging terminal from the charger and plugged it firmly into my NEW partly discharged battery [CAUTION!: need to get the pins correctly oriented!] and Eureka!! it started charging the battery! The pins on my charger are not burnt or corroded and the pins on my battery are new. I believe the Kalkhoff charger simply has a design flaw in its construction which means that batteries which sit on it don't get the pins inserted deeply enough. I had noticed incidentally that my new larger bodied higher capacity battery did not sit as stably on the charger, albeit the pins still *seemed* to insert OK. I have a suspicion that TILLSON's problem with intermittent functioning of his charger may be due to the same problem. I now have a new project in front of me which is to lead an extension wire out of the charger to a 'flying plug-in' connector for the battery. Now, some voltage measurements with the battery operating with the charger: Battery OFF the charger (initial state) :-- pins A-D = 25.8v [battery output pins] pins B-D = 25.8v [battery charging pins] pins B-E = 25.3v [? battery monitoring/communication pins?] Battery ON the charger's corresponding pins (charger then switched ON at mains). pins B-D = 26.0v [ie charger outputting voltage 0.2v above battery initial] pins B-E = 23.0v [the ?'monitoring' pin has 3v less than main pair.] pins D-E confirm 3v difference (with D neg, E 'pos'). At end-of-charging after several hours (charger power transistors gone cold, battery LEDs all gone dark) and battery still connected: pins B-D = 28.9v pins B-E = 28.3v pins D-E = 0.62v [Note decrease in difference voltage.] AND the BONUS. I had thought my old Kalkhoff battery was dead. No LEDs lit on pressing test button, voltage across all 'main' pins A-D, B-D was only 2.4v (two point four); across 'monitoring' pins B-E also 2.4v; across 'battery meter' pins A-C 2.2v. No response putting it into the Panasonic/Kalkhoff charger. For a laugh, I plugged it into the detached pin block of the charger .... and it started charging! I now have an old "Dead" battery charged to 29.2v albeit I suspect its overall capacity is low despite the appropriate voltage. I will try it in due course to see. I remain curious as to what and how the 'monitoring' pin 'E' works on charger and battery. I had thought after finding 10.9 / 12.1 v reverse voltage on that charger pin that pin E was used by the charger to detect a minimum battery voltage of at least > 12v before deciding to operate (this perhaps being related to the 'unsafe' minimum voltage below which one should not charge a Li-Ion cell), but clearly it worked even with a battery voltage of 2.4v . So, what is its function and how is it connected into the circuit(s)? Thanks to all who have helped in this investigation so far!

Thanks for that suggestion. Firstly, to eliminate misunderstanding (because FLECC has referred to the pins in a different numbering sequence) I have put up below a new photo with pins on my old battery & charger numbered A to E. Pin A on the battery connects into + (POS) for the motor on the BIKE but has no connection on the charger. Pin B is also +(POS) and connects to the charger. Pin C is NEG and (I believe) connects to the battery meter on the bike but has no function on the charger because it connects to a charger pin which is a dummy (not connected internally to anything but just used to help register/orientate the battery onto the charger). Pin D is 'common' NEG for both connection to bike and to charger. I have never before quite figured out what Pin E does on battery or charger (it has no connection on the bike) but I have found generally that the voltage on the battery between Pin E (NEG) and either of the two positive pins will mirror the same voltage as found between the two main 'output' pins, A & D. Are you suggesting therefore that the charger has to see a suitable voltage from Pin E of the battery before it will start (and continue) charging? [...And what limits will that voltage have to stay within ......]

Thanks very much indeed for that test & info. I take it there is no voltage when plugged into the mains across ANY pair of pins (when the battery is not connected). That still leaves me with the puzzle of WHAT makes the charger want to start delivering a charge. I think I might try opening the charger to check all the connectors before also speculating whether my new battery is in some way incompatible with the charger ... unless someone with more electronic knowledge understands how this Panasonic charger works...?

Hmm... Thanks.

Thanks. Will do.

Thanks FLECC. Some useful information there. However I would like to be certain that my charger is faulty (or unfixable) before I throw it away. Do you or anyone else know whether this or similar Kalkhoff/Panasonic '29.3v' chargers should show 29v at the charging terminals when plugged into the mains, without the battery plugged into the charger? I would also love to know how & whether the battery communicates/influences the charger in some way BEFORE the charger will start working. Posters NRG & 10mph had some discussion about this charger/battery in the past but the posting did not give me the info I need. I wonder if they still have their chargers?....