Add-on e-bike conversion kit - Swytch or eBay kit?

Electrically assisted bikes, trikes, etc. that are legal in the UK
fastpedaller
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by fastpedaller »

Oldjohnw wrote:I don't know about back pedalling but otherwise, the harder you pedal the more support you get. .
. By 'harder you pedal' does that mean 'the more torque you apply' ? If it means 'the faster you pedal' it's a whole different ball park....... Wheee 40mph here I go!
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Mick F
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Mick F »

Oldjohnw wrote: ............ Freewheel and power switches off, unless you use the override.
Are you saying that you can freewheel but still be under electric power?
Is that legal?
Mick F. Cornwall
scottg
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by scottg »

Mick F wrote:
Oldjohnw wrote: ............ Freewheel and power switches off, unless you use the override.
Are you saying that you can freewheel but still be under electric power?
Is that legal?


Some system have a throttle button, in addition to assist mode controls.
Handy for hill starts.
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Oldjohnw
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Oldjohnw »

I have - button primarily to assist if you have to push a bike. Use it briefly when cycling and freewheeling it will give you some power up to whatever the legal limit is.
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iandusud
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by iandusud »

To answer the OP's original question, there are other (probably better) options. I'm currently looking at buying a 48V rear hub kit from Woosh http://wooshbikes.co.uk/?hubkits

The Swytch "50 mile" kit, even at the discounted pre-order price doesn't seem such a good deal. For £499 you get a 36V 250W front hub motor with a 10Ah battery. Woosh will supply a 36V 250W front hub with a 13Ah battery (30% more range) for £469. I have no connection with Woosh but they seem to have a very good reputation over on the E Bike forum.

With regard to being overtaken by by e-bikes doing 20mph, all kits that comply with the law for use on the road have to be restricted to 25kph / ~15mph and have to be fitted with a pedal sensor so that they only power the bike whilst it is being pedalled forwards. They also have to have a nominal power rating of 250W (although what that actually means seems a bit vague). There are kits which are more powerful, have no pedal sensor etc, but these are designated for "off road" use only, and then would not be legal on bridleways. Of course I'm sure that there are those who fit such kits and use them on the road.
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[XAP]Bob
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by [XAP]Bob »

Technical regulations:
- 250 W, no assistance above 15mph (so no 'cruising at 20' as suggested up thread)
- Throttles used to be legal, but I *think* you have to be pedelec (unless grandfathered) now
- "Walk assist" is a low speed override, so you can push the bike, and have it lift itself up the hill

Real regulations:
- No-one cares unless you a) take the Mickey or b) are involved in a collision.
A shortcut has to be a challenge, otherwise it would just be the way. No situation is so dire that panic cannot make it worse.
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Canuk
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Canuk »

[XAP]Bob wrote:Technical regulations:
- 250 W, no assistance above 15mph (so no 'cruising at 20' as suggested up thread)
- Throttles used to be legal, but I *think* you have to be pedelec (unless grandfathered) now
- "Walk assist" is a low speed override, so you can push the bike, and have it lift itself up the hill

Real regulations:
- No-one cares unless you a) take the Mickey or b) are involved in a collision.


Its very easy to 'chip' current systems to run at 40-50km/h. There are loads of 'how to' videos online. There are bike shops local to me will do it for 40 euro :wink:

I am personally waiting to invest in an E-bike till the latest Panasonic 2170 battery cells become available. Panasonic 18650's have been around for a very long time and are the basis of most electric bikes and car batteries for a good few years now. Their downsides are low range, long recharge times and low discharge cycles before they start to degrade (about 250 cycles, or a year if you charge it 5 times a week).

The new 2170 cells will have 3 times the range, charging from zero to 100% in about 12 minutes (20 for larger batteries), and a discharge cycle life of 1500 cycles while still retaining 80% of their useful charge. A 2170 should last 5-8 years even if charged every day.

They're already being supplied to Tesla for cars and appliances, and are being shipped for aerospace applications. I expect they'll be in the retail chain Mar-May next year. Definitely worth hanging on for. I personally wouldn't put a penny into the current generation of 18650 battery technology driven bikes.
Last edited by Canuk on 13 Dec 2018, 6:03pm, edited 1 time in total.
Canuk
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Canuk »

thelawnet wrote:
Canuk wrote:
The utility cyclist wrote:Loads of old ex laptop 18650s are still coming up on the market from china, one of the biggest scams going and totally unregulated/policed! :x


If you buy Panasonic cells from reputable sellers you won't go far wrong.

Most of which is moot because the brand new 30% more capacity Panasonic 2170 cells are just about to be released (Tesla was first to get their hands on them).


They are called 21700 rather than 2170.


And shouldn't come as a surprise given that they are the same chemistry.


There are about half a dozen different manufacturers of the 2170 (the industry term), amongst them being Samsung, who's cell is reported to outperform the Panasonic cell by a large margin. Its chemistry is so far undisclosed, but is mooted to have a graphene component. They have also developed a graphene battery with twice the energy density of the very best Lithium Ion batteries and will launch it with the next Galaxy 10, probably in March /April which is their normal release cycle. This battery will be a game changer. It's expected to roll out to various applications by June next year. Samsung have heavily invested in a graphene adapted car battery with a range of 600 miles between charges. Tesla is definitely driving this market but other key players are just as determined to deliver. E-bikes will obviously benefit from this 'battery space race'.

The 2170's main advantage is the fast recharge cycle of 12 minutes. Making 'on the go' partial recharges an attractive proposition. Plus they should last at least 2-3 times longer than current Lithium batteries before they start to degrade.
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The utility cyclist
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by The utility cyclist »

Canuk wrote:
The utility cyclist wrote:
thelawnet wrote:There are lots of different 18650 cells and it's literally dangerous to assume they will all be nice ones. Probably safe in this case.

I'm not.keen just because it lacks presumably torque sensor

Loads of old ex laptop 18650s are still coming up on the market from china, one of the biggest scams going and totally unregulated/policed! :x


If you buy Panasonic cells from reputable sellers you won't go far wrong.

Most of which is moot because the brand new 30% more capacity Panasonic 2170 cells are just about to be released (Tesla was first to get their hands on them).


I was just agreeing with 'thelawnet' regarding battery quality, but who can you trust these days not to sell you a product that is dressed up as something it isn't?
And as for the newer battery sizes, well for me as a non e-bike user but who does have a torch that uses 18650s, the new nbatteries are no good if your existing appliance doesn't accept the bloated sizes.
You state a 30% increase in capacity of the 2170 yet 18650s already rated at 3500mAh and with cooling can continuously deliver 30Amps at circa 3100mAh, and when Musk's unit is 37% bigger it's really not impressive at all is it? Also 20 minute recharge IF you don't drain the batteries beyond 80% according to the info I read.
As you said Samsung are apparently also making same size but don't go into mass production for another 2 years, there's also the 20700 Panasonic cells which are also very spendy.

If your existing appliance won't accept the bloated size it's moot as to what the new sized batteries can produce capacity wise. I'm not an ebike user myself but have a torch that does use 18650s, it physically cannot take the new battery size as would all existing products, going forward for e-bikes extra physical size for no greater increase in usable power and more weight is not really an advance either.
Canuk
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Canuk »

The main advantages of the 2170's are 12 minutes recharge from zero to full (I don't know where you get the 80%from but Tesla have been aggressively advertising 0-100% in 20 mins for months now) and 3x the longevity. This alone makes them worth waiting for. They can also be configured into larger capacity battery packs at significantly lower costs compared to 18650's. 18650's in most ebike configurations are only rated 1800Mah, they tend to use the cheapest batteries available. 2170's are kicking off at 3800mah, and Panasonic say they will ramp this up to 5800 mah very quickly. Lower initial cost being the main selling point currently advertised by all parties.
Last edited by Canuk on 13 Dec 2018, 8:08pm, edited 1 time in total.
hemo
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by hemo »

21700 won't be common for a few years yet in ebike batteries, price is too high for cells compared to MJ1 or GA cells.

The EV big car players will get all the grade A/B cells which production can muster, I reckon it will be 5 years at least before good 21700 batteries become common place. Some cells are availanle but these will be the lower grade D,E cells etc, etc.

Sanyo 20700B 6.5 euros only a 15 cdr , Sam 40T 9.5 euros a 30a cdr , Sam 50E 6.75 euros only 10a cdr, Sam 30T 7.95 euros 35a cdr but only 3000mah. They are not game changers yet for ebike use.


18650 is still where it is at for OEM ebikes 3500mah is the best available at the mo with MJ1,GA or the newer LG M36.
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by hemo »

Canuk wrote:The main advantages of the 2170's are 12 minutes recharge from zero to full (I don't know where you get the 80%from but Tesla have been aggressively advertising 0-100% in 20 mins for months now) and 3x the longevity. This alone makes them worth waiting for. They can also be configured into larger capacity battery packs at significantly lower costs compared to 18650's. 18650's in most ebike configurations are only rated 1800Mah, they tend to use the cheapest batteries available. 2170's are kicking off at 3800mah, and Panasonic say they will ramp this up to 5800 mah very quickly. Lower initial cost being the main selling point currently advertised by all parties.


What TESLA and other EV producers claim and what can be done for ebikes are chalk and cheese, EV's will have many cells in parallel and a good few thousand cells across the floor pan. How many in a battery ? 30 will only give 10s3p, You will be lucky to get 500 cycles from a tiddly ebike battery on a 20 min charge. It's well known high C rate charges reduces cell life.
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Canuk »

Here is a pretty good guide to building your own battery packs on the cheap. The spot welder is the most expensive part of the set up but they can be had cheap online and if you club together or plan on making several the savings are there from the get go.

https://www.electricbike.com/home-built-battery-18650s/

Here's a spot welder for just over £100.

https://rover.ebay.com/rover/0/0/0?mpre ... 3132459184
hemo
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by hemo »

AJ101 wrote:Anyone gone down the route of aftermarket e-bike kits? Got to do a commute in January that would be easily do-able it normal clothes if it wasn't for a couple of huge hills in between. Not wanting to go the dedicated cycle clothing / shower / changing rooms kerfuffle, so I'm looking at affordable e-bike kits as an option.

Its a toss up between the Swytch Bike kit which I can get for £360 on pre-order or trying to put something together from e-bay.

Bit worried about the eBay route in terms of battery reliability so the idea of a UK backed kit is appealing. Especially for the money.

Did anyone get a Swytch when they were on the kickstarter thing? How has it been? Was it easy to fit?


'Getting back on track Yose Power.com kits are very good comes out of Berlin or Frankfurt warehouse, quite cheap and relaible with good after sales. If a part has an issue they are quite quick to send out a replacement.

I have one which I run at 48v and have had 28mpoh out of it to see how much power it can handle with out it frying, I dare say it can take a bit more then the 840w I put through it but not as a constant output.

Other wise Woosh bikes are the UK kiddies for top service.
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Mick F
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Re: Add-on e-bike conversion kit - Swytch or eBay kit?

Post by Mick F »

[XAP]Bob wrote:Technical regulations:
- 250 W, no assistance above 15mph (so no 'cruising at 20' as suggested up thread)
- Throttles used to be legal, but I *think* you have to be pedelec (unless grandfathered) now
- "Walk assist" is a low speed override, so you can push the bike, and have it lift itself up the hill

Real regulations:
- No-one cares unless you a) take the Mickey or b) are involved in a collision.
This is what I thought.
Who actually cares or knows?
Mick F. Cornwall
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