tongxinpete

Sold it to a local tinkerer / enthusiast - he may put a suitable LiPo battery on, has built other machines inc a converted Pashley. He arrived in a 30 year old Volvo estate - they do not build them like they used to!

Have dropped the price on this to £100 if anyone interested. Think LiPo4 battpack a good potential upgrade because it would work with existing motor controller & perhaps chargers? A high C rate for the 36A start amps at stall ideal, Think 20A is an absolute max when moving say up a very steep hill, most of the time far less. Advertised elsewhere

I put an ammeter on the bike, 36A momentry starting from stall, commonly around 20A & 2A if the wheel is running off the ground. So this agrees with the 40A BMS if up grading the motor Motor is a Parvalux EMD 50 - 446B TGA Part 3110 039, I checked if available in case it ever failed, I have not used it much bought used for the wife A strong frame & front forks, could also take a heavy duty front hub motor

Have for sale a TGA 24 v Crank Drive 20 inch bike, all working OK, with spare & original charger. Has SLA batt system. Drives through Sturmey 3 speed rear wheel. Works fine as is or could be basis for say hub motor crank drive project. Some rust on rims but comes with spare donor wheels with good rims to rebuild hubs into if buyer inclined. Having to sell because of downsizing. £ 140 Telford, Shropshire

I remembered that Bafang used to offer a range of windings & gearings to suit different rim dia.s - the slowest - aimed at 26'' off road MTB users may be an idea in a 700 wheel. Do not buy this from BMSbatt - as it is pot luck which version they send. A smaller option is OutRider - was Tongxin - they had likewise in a smaller lower amp motor - aimed at different wheel sizes - I bought one off 'Brett White' - he stocked a 13.7 mph top speed one to give a bit more torque in a 26'' rim - the factory did have a lower speed more torque one than this. Mine still works - Max draw about 11A - so good for smaller battpacks

I built a batt from LiFePo4 pouch cells from BMSbattery some years ago - using their BMS. It is Ok when working, but I lost one cell due to 'puffing' - I could never work out why. I replaced this with a similar cell from AliExpress (cost £15 with shipping, replacement single cell from BMSbatt unaffordable) - again worked well for a time - but now I am experiencing cut off when climbing a hill (So if 15A is drawn for 2 mins) - If I unplug the controller feed & refit, it clears until the next time. My van went off road, I needed an alternative - this is what I found. I just feel it is like trying to run a taxi service with a 1903 DeDion. I do have a vruzend kit somewhere - but not just now time to pursue the hobby. I really need more reliability. I feel the motors & controllers now a mature technology - or 'done deal' - not so batts. Re the weight, I weigh 200 Lb, bike with hub motor 40 Lb - so the weight of batts is a relatively small part of total, when it comes to hill climb calcs. I did get an interesting reply from Zinc Five, the patent holders of the Ni Zn improvements. They say they are a year away from having 'light traction batts' available in warehouses for the general public - aiming at golf cart owners, disabled scooters, ebikes, & RV lesuire. They did say they expect a life of 1K +cycles @ 60% D.O.D & 1.5C. Weight is half that of SLA & they have a true 1C rating. They will series charge with no individual cell voltage runaway. HV cut off important, along with a max time on charge in case this point is never reached. Temp probe in batts ideal. these best in charger. Charge at 0.5 to 1C Also LV cut off during discharge required- this (customisable) we have already in motor controllers. Clearly if this is true the Zinc Five batt a better bet than the Chinese one.

I went the other way & built a 201 rpm Q100 into a 24'' rear wheel, keeping the frame & front wheel as a basic 26'' ATB style. The motor draws 15A max @ nominal 36V . This gives a decent hill assist without too much sacrifice of speed. The saddle is only 1'' nearer the ground, I weigh 200Lb the bike without a motor or batt 35 Lb. I would rate this as adequate & better than the Tongxin in a 26'' wheel / or a c'lyte 408 in a 20''. All I am saying is a small motor would do very little in a 700 unless you live somewhere extremely flat. The stock controller was outing about 12.5A - I did hack it to 15A with advice from D8veh - he said I could have gone to 18A - but I did not because of batt limitations. The controllers could come as standard anywhere between 11.5A & 15A I was told as quality control is not rigorous on them. A disc brake does not care what the rim size is. I had to make a plate to carry a rim brake caliper as this was my set up

I am only now an occasional rider thanks to other commitments. I remember researching Li-ion calendar life vs Li Po4 - At the time you needed to be on the bike 4 days a week to use up the 2000 cycles in 10 yr calendar life of LiPo4, & 3 days a week over 5 yrs for the 800 cycles of Li- ion Apart from the difficulties associated with lithium it would seem a poor choice for anyone only using the bike now and again at weekends. I built a pack from LiPo4 pouch cells, fine when working but BMS signal wires vibrate off, pouch cells fail etc. I am honestly thinking of going back to the heavy but reliable SLA I originally used for years, as kept charged & keeping a second charger at my usual destination they served me well. I did come across this possibility http://www.neucell.net/applications.asp They claim 500 cycles @ 80% D.O.D (same as SLA) but are half the weight of 3 x 12 Ah SLA bricks, claim to be about 60 to 70% price of Li ion (actually the price per cycle works out the same - about 12p) The killer is no doubt the shipping cost of a 6Kg batt. There was once mooted a Chengzhu to Poland express goods train, taking 5 days per 1 way journey. Not sure if this ever happened - if so ideal for many things - not least Li batts / cells. When I last spoke with Neucell they could not supply the charger. I did find a Chinese ebay supplier that could set his chargers to suit Ni Zn - he knew the cut off voltage saying this chemistry was known in China - after SLA's were 'officially' banned there, at least on new ebikes - rather than home conversions. Any thoughts ?

To be honest I was more wondering what motor it used - probably a gear one owing to the small dia of the rims. I guess from my own measurements of motors that it does not draw a lot more than 200 w once up to speed on the flat - at least at 15 mph or less. Above that wind resistance becomes more of a factor I imagine. It was more the hill climbing ability that spiked my interest

Saw these 'fat tyre scooters' on Alibaba https://www.alibaba.com/product-detail/Fat-Tire-EEC-COC-CE-1000W_62136904805.html?spm=a2700.7735675.normalList.17.ZkLARB&s=p It claims up to 50 kmh, climb angle of 25 / 30 degrees, all are 60v, 12 or 20 Ah batt. Some have lights / indicators & claim an E.U. standard. This particular one has a folding rear rack - meant for golf bags but ideal for shopping / work tools etc. I gather they are a new to 2019 product - I have not seen them before. Hydraulic disc brakes, hydraulic front forks, hardtail but hydraulic seat mount. I really wondered if they are comfortably sized for a taller western rider & if anyone out there had tried one (perhaps when abroad)

I have a 408 from about 2007, & a 408 clone from 2005, (Golden Island HBM 36) - Both direct motors laced into 20'' Front wheels. The HBM 36 is now running on a self learning sensored 15A @ nom 36v. Some years ago I was told by E crazyman (supplier of controllers on ebay) that this motor could take 500W or more. .Back then I was on SLA batts so no go for me The 408 I have heard of more amps going through them - Crystalyte suggest the present 408 can take 40A @ nominal 48V BUT it now has phase wires of 2.5mm CSA. I was looking at running either of above on 25A @ nominal 36V - to give better peak torque, has anyone done this on here. I have some BMX 20'' front forks to put the wheel in. Thinking of building a Vruzend Batt to run it - have some cells but thinking of going bigger on this - Reason is I have the motors, chargers, some cells, all I need is a universal controller. Granted direct motors are not so much used now.

Thanks again all, for the advice. Not sure who to go with on the spokes as bms would work out rather cheaper. Interestingly the spokes do not add to the shipping costs! I did once try to interest them in the Chengzhou to Lodz (Poland) express goods train - ideal for batteries

Thanks NJS & all, I am a bit doubtful in that I cannot tell how the nipples supplied by bms will sit in the rim holes - need this for the ERD (have the double wall rim on its way). Is the 12g & 1X pattern practical? I am pretty sure I have seen one of these done 1X on here or ES. Agree windows 10 is a pain, updates seem to raise as many issues as they solve!

Does anyone have a drawing for the above motor, what I need is the flange dia (spoke hole centre to centre across the flange), the flange width, & the offset info for a rear wheel, as here https://leonard.io/edd/howtomeasure I hope to get the spokes from bmsbatt at the same time as the motor, thinking of going 1X pattern as I only just made it with 3X when I put a Q100 into a 24'' rim. What gauge for this setup best, eg 12? There used to be drawings for the motor on the bmsbatt site, seem to have disappeared.

PSB America - on freesat showed ;In Search of the Better Battery, these things often are repeated - or it might be somewhere on the net. Showed various Li cells, how they are made & common causes of failure, also various promising chemistries under development. One thing they did not mention is a claimed breakthrough by US Navy Research - into Nickel Zinc, a means of preventing dendrite formation . This has been licenced to a company looking to exploit the research. Potentially much safer & will self balance in series. Also much lower cost & plentiful ingredients. Like to charge at 0.5 to 1 C - so fast charging - not a problem in the size likely used on a bike. Also GKN & a Chinese maker have both separately developed a 2 speed planetary transmission for elec cars allowing on the go auto shifts as needed. There was always a great argument if more than one mech speed was needed. There is no clutch to worry about & reversing is electrically achieved by the motor. These two things together if viable could make for a great electric vehicle.