e-bike build

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tempsperdu
Posts: 123
Joined: 9 Jan 2014, 8:31pm

e-bike build

Post by tempsperdu »

At 75 I thought I had built my last bike but I now find myself looking for the ‘ideal’ e-bike’ but not finding it or not being able to afford it when I do.
Spec would be a flat bar e-gravel with Rohloff and belt drive. Carbon forks up to 2.5” tyres and SKS mudguard room. Say 100km range.
Other than invalidating every guarantee that would come with a new bike if I modified it is it a simple home change over or is it like chipping a car and needs a software set up/change?
Thought I might try and find a duff used e-bike and replace everything but haven’t costed it yet.
Anyone already been there and done? Not looking for one of those hot rod machines just an e-bike to take the sting out of the hills and ease my knees for a few more years.
rareposter
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Joined: 27 Aug 2014, 2:40pm

Re: e-bike build

Post by rareposter »

e-bike with a Rohloff hubs aren't exactly common (some German manufacturers have that kind of thing in their range..) and it'll be VERY expensive. A Rohloff is already £1300 on its own; build it into an e-bike and you'll be well up in the high four figures.

If you can find a Rohloff-equipped flat bar gravel bike, you could put something like this into it:
https://www.swytchbike.com/p/universal- ... rsion-kit/

But that has half the range you're after. For an off-the shelf e-bike with that sort of range, again, you'd be at the top end of the market or possibly adding a range extender battery - which then means carrying an additional battery. That in itself isn't a problem but paradoxically, carrying the extra weight then lowers the range anyway.

There's something like this:
https://www.specializedconceptstore.co. ... o-5-0-igh/

enviolo hub gear (which is excellent, it's a stepless transmission), belt drive, 2.3" tyres on 650b wheels and designed for sort of trekking / mixed surface riding... But suspension forks rather than carbon rigid...
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531colin
Posts: 14640
Joined: 4 Dec 2009, 6:56pm
Location: North Yorkshire

Re: e-bike build

Post by 531colin »

I have built up a Genesis Longitude frame with chain driven Rohloff gearing, and a Tongsheng TSDZ2 mid motor.
I fitted the biggest Rohloff sprocket (21T?) which with the 42T Tongsheng chainwheel gives almost wall-climbing gears. I was interested in picking a sensible ratio for the Rohloff gear 11, which is direct drive.
To be fair, its excellent to ride. I like to do tracks, and on tracks I find I do a lot of the bike control with my feet....a quick push or two to get over an obstacle, or a gentle trickle to get round one. The Tongsheng responds seamlessly, if there is any delay or over-run in the response I'm completely unaware of it. Its one which looks at how hard you pedal, and makes a contribution proportional to your effort. It obviously drives through the gears, which gives really good climbing.
A local track to me which I could climb easily say 3 years ago had become impossible. With the electric, I set it on level 2 (of 4) and went up so easily I was giggling all the way up!
I didn't fancy a hub motor, or sensing which only looks at whether the pedals are turning or not.

There is a snag. The thing is so damned heavy I'm reluctant to take it anywhere I might encounter a problem. Something like a locked gate, or a difficult footbridge, or a washed-out bit of track I couldn't ride would have me turning round, although there is "walk assist" . I suppose thats only really a question of pride, and actually not so different to what would happen if I was on a regular bike. I can get it onto the repair stand if I take the battery off.......

There is some stuff in this thread viewtopic.php?t=137395&hilit=tongsheng+rohloff&start=45 and you might find more if you do a search of my posts eg for tongsheng and rohloff.
NickJP
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Joined: 24 Sep 2018, 7:11pm

Re: e-bike build

Post by NickJP »

My wife, who has been plagued by ankle and hamstring problems on long rides in recent years, recently purchased herself a Trek Domane LT+ e-bike. The bike was quite nicely specced - DT Swiss wheels, Ultegra components, Fazua mid-drive motor, and has the Trek Isospeed couplers front and rear, which she says makes it noticeably more comfortable over bumpy roads than her other road bikes. She doesn't like drop handlebars, so I changed it over to flat bars and also lowered the gearing a bit from what was supplied. The bike has been a real success. Trek claim a weight just under 14Kg complete with motor and battery (I haven't weighed it), and if you want to ride it unassisted, the motor/battery can be removed and replaced with a cover, which brings with weight down to 11Kg or so. The bike came with 32mm tyres, and looking at the clearance, 40mm or so is probably the largest size that would fit under the fork crown and between the chainstays.

As for the range, she usually only turns on the assist on hills, and on numerous ride over 80km or so, there's usually still about 40% of battery remaining at the end of the ride. It's definitely not a cheap purchase, though.
PXL_20220127_031036929.jpg
rjb
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Joined: 11 Jan 2007, 10:25am
Location: Somerset (originally 60/70's Plymouth)

Re: e-bike build

Post by rjb »

+1 for the Tongsheng. I fitted the 250watt motor to the tandem. Everything Colin says and It now sails up the hills at double the speed it did previously without me having to stand up out of the saddle and haul Swmbo over the top. I can even lift the whole thing with battery attached and turn it over if we get a puncture. ( Without the missus on as well) :lol:
For us one of the biggest advantages is the way the electric assist comes on as soon as you pull away from stationary. No more struggling to get up to speed when pulling out from junctions etc. It cuts in within an 1/8 of a revolution of the crank and we have never noticed any overun.
At the last count:- Peugeot 531 pro, Dawes Discovery Tandem, Dawes Kingpin, Raleigh 20, Falcon K2 MTB dropped bar tourer, Longstaff trike conversion on a Giant XTC 840 :D
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Vantage
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Re: e-bike build

Post by Vantage »

First thing you wanna do is think about what sort of motor you want and what you want from it.
A front hub motor would be good enough for a trip to the pub/shops etc. A rear hub motor would give you more control over your speed as you pedal and I think would give better mileage.
As with 531colin and rjb I went for a mid drive setup. This replaces the bottom bracket and chainset of your bike with the motor and its own chainset.
I personally went for a Bafang BBSO1b motor because basically, it's the first system that came up on my searches and they are sold everywhere. It's a little more crude than the Tongsheng I believe in that it uses cadence to judge how much power to add. The faster you pedal, the more it helps.The Tongsheng uses torque sensing. The harder you pedal, the more it helps. They both have their pro's and con's but you'' find more detail about those in the electric bikes part of the forum.
You ask about software. All systems use it but they don't necessarily need it to be tweaked. Most people I think find the stock settings do the job perfectly adequately. I tweaked mine. Just because I could :mrgreen:
Other than a bit of wiring routing, it is indeed a simple case of bolting the thing on and pedalling away.
As for cost, I'm not sure about the Tongsheng. My Bafang motor alone goes for around £300 for which you'll usually get a choice of chainring size and which control display to use. Your battery can cost anywhere in the region of £150 to north of £400.
I bought mine as a package deal which included everything for just under £600.
There are of course other brands with bigger premiums but I've no idea how much (if at all) better they are.
From a legal standpoint, your motor must be limited to 250w and mustn't exceed 15mph. I'm not sure about Tongsheng, but someone mustn't have told Bafang about these rules as though mine is 250w, it's dragged me upwards of 20mph a few times. Bafang also have motors going north of 1500w! Why, I've no idea. 250w has no problem dragging me @68kg plus the bike at another 28kg up 15% hills using 50% of it's available power. And I'm no muscle mary.
Bill


“Ride as much or as little, or as long or as short as you feel. But ride.” ~ Eddy Merckx
It's a rich man whos children run to him when his pockets are empty.
scottg
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Location: Highland Heights Kentucky,, USA

Re: e-bike build

Post by scottg »

531colin wrote: 3 Aug 2022, 7:12pm[snip]. I can get it onto the repair stand if I take the battery off.......
[snip]
Power lift Park Stand, or some Royal Navy surplus block & tackle off the Victory ?
https://www.parktool.com/en-us/product/ ... egory=Shop

I've sympathy for you, the first e-bike in the family was a Surly Troll with a Bionix kit,
rack battery with hub motor. Quite the unwieldy tail heavy beast and heavy too.
Even parking was extra work.
+++++++++++++++++++++++++
Deutsche Luftschiffahrts-AG
+++++++++++++++++++++++++
tempsperdu
Posts: 123
Joined: 9 Jan 2014, 8:31pm

Re: e-bike build

Post by tempsperdu »

Thanks so much everyone I had no idea about bolt on mid-motors.
I have seen hub motors and the shiny fully built offerings but these home brew ones sound just the job.
What is the ground clearance like with the Bafang and Tongshen?
Also waterproofness (?) of these two? One of my favourite rides up on to Woodbury Common has a water splash or wet feet depending on water flow.

An idea that just occurred to me is to check out AliExpress and see if I can find a F&F that will take a motor.

I will keep this updated if it goes ahead.
Do like the look of that Trek though.
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Vantage
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Re: e-bike build

Post by Vantage »

On mine the motor hangs at about the same height as the chainset but is further forward of the bottom bracket. Almost dead centre between the wheels. I was wary of it taking a bashing at first but so far it's only had one minor knock and that was while trying to tackle something silly big and pointy. Any bike would've hit it.
As far as I'm aware, both motors will be OK in torrential rain but going through deep water or pressure washing is best avoided. Same as any bike component really.
Bill


“Ride as much or as little, or as long or as short as you feel. But ride.” ~ Eddy Merckx
It's a rich man whos children run to him when his pockets are empty.
djsb
Posts: 43
Joined: 25 Jul 2010, 6:06pm
Location: Hertfordshire

Re: e-bike build

Post by djsb »

According to Riesse and Muller they are going to bring out a few city/urban E Bikes next year.

https://www.youtube.com/watch?v=IpwmZKRl-K4

I have one of their Delite GX Rohloff models with full suspension that I bought about 3 years ago. I thought about building an EBike centred around a Montague Paratrooper Pro folding bike with a Bafang mid-drive motor and batteries hanging from the cross tube. I bought the Paratrooper anyway as it's useful for combining with bus travel, and it was on sale at half price. Got the R&M later and loving it. I haven't had to convert the folding bike, as I'm happy with it as it is (and folding ebikes aren't allowed on buses because of the fire risk).
NickJP
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Joined: 24 Sep 2018, 7:11pm

Re: e-bike build

Post by NickJP »

How about this: https://ebiketips.road.cc/content/revie ... hloff-3883.

All you need is a spare £10K or so.
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Cugel
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Re: e-bike build

Post by Cugel »

tempsperdu wrote: 4 Aug 2022, 2:06pm Thanks so much everyone I had no idea about bolt on mid-motors.
I have seen hub motors and the shiny fully built offerings but these home brew ones sound just the job.
What is the ground clearance like with the Bafang and Tongshen?
Also waterproofness (?) of these two? One of my favourite rides up on to Woodbury Common has a water splash or wet feet depending on water flow.

An idea that just occurred to me is to check out AliExpress and see if I can find a F&F that will take a motor.

I will keep this updated if it goes ahead.
Do like the look of that Trek though.
If you like the Trek, consider one of these - a Fazua-motored bike like the Trek but much less expensive for a similar thing. Currently 20% off list price.

https://www.wiggle.co.uk/vitus-e-substa ... 105-2022-1
Vitus-E-Substance-Carbon-Road-E-Bike-105-2022-01.jpg
Well, a similar thing to a point. Although this version is sold as a road bike it has the same frame as the version sold as a gravel bike. The difference is that the road version has 105 double chainset gears, road wheels with 25mm (27mm in reality) tyres and standard road handlebars rather than those flared gravel ones. But it'll take fat tyres as well as mudguards and a pannier rack

I just bought one to become my new winter bike, shopping bike and gravel bike (for forest roads). It's excellent, although I want to swap the 50 chain ring for a 46. Already I have a pair of Hunt gravel wheels I already had in it, shod with 45mm Schwalbe G-One tyres, as well as a rear rack. A marvellous thing to ride.

Mudguards on for winter, before long.

Very good value for such a bike with A Fazua motor and a carbon frame. Very versatile too - gravel, tourer, audax and even a bit racy with those skinny wheels & tyres they put in it.

********
The Fazua e-motor is a fine thing if you don't want either an electric motorbike (Bosch) or a hub motor that's rather weak on step hills (Mahle e-motion). It can also be taken out, leaving you with an ordinary bike 3kg+ lighter. And you can swap any part you like, particularly wheels, without issue.

And its already built, so no messing about with add-ons parts that make your old bike look like a 1050s moped. :-)

Cugel
“Words ought to be a little wild, for they are the assaults of thoughts on the unthinking."
John Maynard Keynes
saudidave
Posts: 556
Joined: 16 Jan 2009, 12:22am

Re: e-bike build

Post by saudidave »

You can get a very good spec utility bike, 21/24 speed Dawes et al for £250.00 on ebay or Gumtree; as new and very often little or unused.
£500/600 gets you an electric front wheel conversion kit and another couple of hundred you can do it with a mid drive. So a good, reliable set up for a grand or so

The other route is a nearly new ebike off ebay or Gumtree. I recently accquired a £3,000.00 Raleigh Centros step thru, 500 Wh battery, hydraulic disc brakes, 8 speed Nexus, Gates belt drive & Bosch active line central drive, 14 miles from new, for £1800.00. There are loads available out there, initial purchase funded by furlough dosh, then abandoned when they realised you still have to pedal it. Now utility bills are getting stupid they are unloading them for relative peanuts.
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