Popular Post Lord Gruntfuttock Posted November 17, 2019 Popular Post Share Posted November 17, 2019 Background I've been intrigued by the idea of electrifying an old bicycle for a while, possibly as a test run for doing an electric hub classic scooter. No real plans but interested in the concept so started squirreling bits away. I don't want a balls out speed machine, nor a boomer spec mild pedal assist, so went mid range 350W geared front hub motor, easy to install, small enough to be relatively unobtrusive (130mm diameter) but big enough to pull you along around 30km/h for an hr or so. Grabbed this one on Ali 11.11 sale and it's on the way (36V 350W - $177 delivered)... Originally wanted to do my Raleigh Twenty, but spent so much on the oddball rims and spokes I'd prefer to keep it as is... Also looked at doing my Czech folding Eska bike, but those wheels are even smaller and low top speed may be an issue... Then I saw this one online, and realised how wrong smaller ebikes can look (granted it has a bigger direct drive hub), but still super dorky... so now looking at my old Raleigh/BSA full size jobs, have a few hanging in the shed. I like the old Sturmey Archer rear hub so a combo of that and the lectric front wheel seems a good recipe? (Motor hub not much bigger than the dyno-hub they came with as an option). Have to see if motor will fit forks first before making a decision on base vehicle. Like this old BSA Sports though... Came from O'Shea cycles in Ch'ch... I have a couple of suitable SA rear hubs and new alloy rims set aside, and reckon with the patina this thing could look pretty cool with a sympathetic ehub... Power pack Batteries are bulky and expensive and you have to compromise size/weight/cost vs range, so I bought one of these after seeing them in the moped/motorbike electric conversion thread, the Vruzend battery pack - (10S, 3P kit for $44USD) as they look a good way to avoid the solder vs spot weld arguments/faffing about... And the 11.11 sale on Ali encouraged me to order some Polymide tape (kapton), 220mm PVC heatshrink tube, a 10S 36V 15A Li-ion BMS and a 5.5mm nut driver tool, so all up I'm into this around $270 so far... So still need a controller and charger, plus spokes to suit whatever rim I end up using, but have enough to carry on with. Also need batteries, the no-post ruling is a ballache, and at around $10ea in NZ I'm looking at $300+ which is a bit daunting. Might look at scavenging laptop cells or similar, but got some time to look into this... Anyways, long term project but parts ordered, by the time I actually build anything technology will have moved on and this'll be proper OS... 11 1 Quote Link to comment Share on other sites More sharing options...
Willdat? Posted November 17, 2019 Share Posted November 17, 2019 28 minutes ago, Lord Gruntfuttock said: Awesome project idea! Assuming you're riding Invercargill, front hub drive will be sweet. They don't love steep up hills. There's a place in Russia that seems to have success sending li-ion cells. Will see if I can remember where. Do the hub suppliers also sell a speed controller? Helps get rid of the few compatability issues that can arise. Awesome project! 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 17, 2019 Author Share Posted November 17, 2019 Yeah compatability was an issue I was concerned about. Will look into supplier, cheers... Quote Link to comment Share on other sites More sharing options...
M.H. Posted November 17, 2019 Share Posted November 17, 2019 What sort of capacity will the battery pack need to have? Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 17, 2019 Author Share Posted November 17, 2019 Hard to say. Depends on the 18650 cells. The 10S gives me 36V, but only have 3 in parallel so if I have 2600mAh cells that'll give me 7.8Ah. 3400mAh cells would give 10.2Ah. I don't know what the 350W rating actually means (constant, peak?) but assuming face value figures, it will draw around 10A at full noise, so should run for around an hr at that. Real world figures will be far different I expect... Of course more batteries is better, but there are huge cost, size and weight considerations. 48V may have been a better option too, I just went for something not too bulky I can hopefully conceal in a saddlebag or similar. And the no-solder battery pack kit came in that 10S 3P configuration. (I'm fine with soldering but apparently it can damage the cells and spot welding is better)... If I had access to unlimited cells and a spot welder I would look at different methods... Quote Link to comment Share on other sites More sharing options...
M.H. Posted November 17, 2019 Share Posted November 17, 2019 Do you have to run the 18650 cells? I have 5s 5000mah lipos for my rc stuff, could run 4x of them to give 10s 10000mah 1 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 17, 2019 Author Share Posted November 17, 2019 Don't see why not, as long as correct voltage motor. I even looked at using my DeWalt tool batteries... There's a few calculators out there, this is a screenshot of electricbikesimulator.com. Quote Link to comment Share on other sites More sharing options...
M.H. Posted November 17, 2019 Share Posted November 17, 2019 They are 3.7 nominal voltage per cell so would be 37v. I get mine from revolectrix. They happily ship them and are pretty good price, wouldn't even need the fancy high discharge rate ones 2 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 18, 2019 Author Share Posted November 18, 2019 Aaand just bought 30 x Panasonic 3000mAh batts on tardme for $100. Apparently in new condition, tested etc. Will see how they go... 2 Quote Link to comment Share on other sites More sharing options...
tortron Posted November 18, 2019 Share Posted November 18, 2019 12 hours ago, Lord Gruntfuttock said: Hard to say. Depends on the 18650 cells. The 10S gives me 36V, but only have 3 in parallel so if I have 2600mAh cells that'll give me 7.8Ah. 3400mAh cells would give 10.2Ah. I don't know what the 350W rating actually means (constant, peak?) but assuming face value figures, it will draw around 10A at full noise, so should run for around an hr at that. Real world figures will be far different I expect... Of course more batteries is better, but there are huge cost, size and weight considerations. 48V may have been a better option too, I just went for something not too bulky I can hopefully conceal in a saddlebag or similar. And the no-solder battery pack kit came in that 10S 3P configuration. (I'm fine with soldering but apparently it can damage the cells and spot welding is better)... If I had access to unlimited cells and a spot welder I would look at different methods... @Ghostchips made a battery tab spot welder once 1 Quote Link to comment Share on other sites More sharing options...
Willdat? Posted November 18, 2019 Share Posted November 18, 2019 22 hours ago, Lord Gruntfuttock said: I don't know what the 350W rating actually means (constant, peak?) but assuming face value figures, it will draw around 10A at full noise, so should run for around an hr at that. Real world figures will be far different I expect... 350W tends to be the constant rating, and a pretty conservative one at that. The 350W motors we run will hit 750W under acceleration. We run 24V and 40A fuses... 3 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 18, 2019 Author Share Posted November 18, 2019 Good info, cheers. I'm flying blind here, just bunging things together to see how it goes... Quote Link to comment Share on other sites More sharing options...
Willdat? Posted November 18, 2019 Share Posted November 18, 2019 13 minutes ago, Lord Gruntfuttock said: Good info, cheers. I'm flying blind here, just bunging things together to see how it goes... Our 48V 1kW motors actually run a 2.2kW speed controller, again with a 40A fuse - not great for the longevity of the motors, but good for performance! We don't have pedal assist, so the bit of extra oomph to get you off the line is a winner. 2 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 22, 2019 Author Share Posted November 22, 2019 Did an inventory of bits in the shed yesterday. Got a new set of Sun Ringle CR18 26 x 1 3/4" alloy rims looking for a home... And a 1972 Sturmey Archer AW 3-spd hub that looks ok... And some packages arrived today, batteries from Dunedin... Think these are pretty good spec, Panasonic 3200mAh...? And most exciting, hub motor has arrived, 11 days from order, pretty sweet... Except, it's bloody 48V. Checked and def ordered 36V. Wouldn't be a major but I've ordered BMS, batteries, battery holder system and charger all for 36V configuration. Have notified Mr Ali, will see how we get on (could be a win, could be a PIA)... It came with this fitting from motor (3 power and 6 Hall effect connectors?) guessing there's a socket to suit, don't think the cable included fits, only had a quick look. [edit, yep has appropriate connector, was looking at wrong end)... Good thing is I can measure up hub for spokes, looks like 5mm wide flanges, 42.5mm apart, 119mm flange diameter (haven't looked at any offset yet). The Sturmey AW is 65mm flange diameter and 27mm from centre to each side. So until I hear back from Ali I guess I can order spokes and look at controllers... 2 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 22, 2019 Author Share Posted November 22, 2019 So looks like a win... 4 Quote Link to comment Share on other sites More sharing options...
Chris.QCR Posted November 22, 2019 Share Posted November 22, 2019 So now you have to build two bikes ? 5 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted November 22, 2019 Author Share Posted November 22, 2019 looks like it... 2 Quote Link to comment Share on other sites More sharing options...
datlow Posted November 22, 2019 Share Posted November 22, 2019 2 wheel drive plz 8 Quote Link to comment Share on other sites More sharing options...
Chris.QCR Posted November 22, 2019 Share Posted November 22, 2019 Maybe ya could do a vintage kids trike and do some electric skids 4 Quote Link to comment Share on other sites More sharing options...
Lord Gruntfuttock Posted December 1, 2019 Author Share Posted December 1, 2019 Worked over the weekend, but did some foraging for bits amongst the junk at home (after seeing the stupid prices on trademe for vintage bits). Pulled this ratty seat off an old Raleigh in the shed... And looked like it would suit the 70s? vinyl Brooks cover I scored for $10 on the tard some time ago... Sweet... And on the spare Ali seat post I bought for my Raleigh Twenty, was too short for that but perfect for this... After I cleaned up the hub I found some other bits I had squirreled away for just such a project, thought I had a shift lever somewhere, glad I didn't buy another one... Still need some pedals and a carrier, but things coming together... [Edit] Found a couple of carriers on donor bikes I could use, and have ordered these... MKS for $19US. Far better than the junk ones I've seen elsewhere, and should look great in white with that seat... 1 Quote Link to comment Share on other sites More sharing options...
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