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Retro fit electric bike
skydivepaul - 12/4/20 at 09:53 PM

Anyone on here got experience of retrofitting an electric motor to a pushbike? I've seen a few nice off the shelf bikes like the trek mountain bike but these run in at over £2k
I've got a decent mountain bike and living in a very hilly area a bit of electric assistance every now and then would definitely mean i would go out on it more.
Always in the back of my mind is the 5 minute hill to climb to get back home, which can put me off going out if i don't feel that energised.
Seen a few kits on flea bay that look decent and have good reviews elsewhere on the internet
Which way to go.
Rear wheel hub?
Front wheel hub?
Other?
Some of the kits don't come with batteries as i guess they expect you to source your own. A quick search and some of the batteries at £200

Anyone on here got one or done a conversion?


rf900rush - 12/4/20 at 11:05 PM

Yes I did this 2 years ago Apr 2018 to my mountain bike.
A bit of work needed doing to get the disk brake going, but i am sure any locost builder could do this.

I used a cheap-ish Chinese front hub with controller.
Like this 250w front option.
EBAY LINK
eBay Item

Luckily I have some batteries. Just a bit big. 12off 3.2V lithium at 25Amp hr

Used I a fair bit, mainly on the road.

No problems so far.


swanny - 13/4/20 at 07:24 AM

ive got a swytch kit.

definitely makes me use the bike more than i did.

some teething troubles, but the company sent new bits quite quickly.

it was less than a full electric so i treat it a bit like a kit car, might need the odd tweak here and there but genuinely love using it.

great passing MAMILs on big hills and watching them try to figure out how a fat lad on a massive hybrid eased psst them!


ianhurley20 - 13/4/20 at 08:20 AM

In the mid sixties got an old lorry sarter motor, mounted it with a home made bracket behind the seat, used a sprocket and chain drive to the rear hub and a lorry battery where the pedals were and a pair of jump leads with no switch. Lethal, o to flat out instantly. Didn't use it much. Got an 8mm film of it somewhere in the loft. Wouldn't recomend this route. Did have a cheap powabike several years ago worked well for a 10 mile commute each way but not as light as current generation bikes, maybe an old second hand one would work? They do a good but expensive conversion kit as well I believe


Mr Whippy - 13/4/20 at 08:25 AM

Might consider one for my home built recruitment as its slow going up hills. I had considered making it a hybrid by ditching the chain and turning a generator instead which charges a battery which then though a motor drives the wheels...that way my pedal speed and load should be constant regardless of the terrain.

[Edited on 13/4/20 by Mr Whippy]


tegwin - 13/4/20 at 10:31 AM

Loads of discussions about this online but the vibes I got were that a mid drive was the way to go if you wanted to maintain normal handling. You don’t see many e mtbs with hub motors. Probably for good reason.

Check out the bafang mid drive units.

Remember that legally in the uk the max motor power is 250w and must cut out at 15mph.... although I do hear the 500w motor shifts 🤣.


skydivepaul - 13/4/20 at 11:25 AM

Thanks for the replies. I think the mid drive is the best solution but is the priciest.
Not sure about the front hub types as they may affect handling. The rear hub seams the best compromise.
Online kits are around £140- £200 which seems ok without batteries. The batteries look they are approx £200, may have to do more searching


rf900rush - 13/4/20 at 11:57 AM

Mine is front hub
At 250watts (legal) no problems with handling on the road. A bit of wheel spin if wet an slippery.
Although it makes the front a bit heavy, and lifting the front wheel more of a pain.

If I was to do another with just 250w, I would still go front drive just for simplicity.
Rear or center drive if I was going off road and more serious use.

If you are ever down south I have some batteries left over, like these LINK

Not a small option but I use less than 20% on a 12mile commute

Just a note there is now way to send these by post , and I have tried.

Bike
Bike

bike
bike


Mr Whippy - 13/4/20 at 12:17 PM

that's an impressive price for lithium cells


mangogrooveworkshop - 13/4/20 at 12:20 PM

Sell the existing bike and buy a https://www.decathlon.co.uk/stilus-full-suspension-electric-mountain-bike-sram-sx-id_8581581.html


Or get the bafang mid-drive motor from andy Kirby on youtube . Half the issue with the cheaper kits is the ingress of water into the electrics
hub drive is ok but its not good for anything else than flat stuff

I couldn't be arsed with another project so I have purchased a Cube with full suspension gen 4 bosch with the 750w battery. Your local government energy council are giving out loans and grants through the cycle to work scheme.

better to be riding fixing my health than creating another stress


Mr Whippy - 13/4/20 at 12:30 PM

quote:
Originally posted by tegwin

Remember that legally in the uk the max motor power is 250w and must cut out at 15mph.... although I do hear the 500w motor shifts 🤣.




It's a shame as usual in the UK they slap on restrictions on anything that could potentially open up alternative clean transport options. Red flag Britain.


skydivepaul - 13/4/20 at 01:05 PM

quote:
Originally posted by mangogrooveworkshop
Sell the existing bike and buy a https://www.decathlon.co.uk/stilus-full-suspension-electric-mountain-bike-sram-sx-id_8581581.html


Or get the bafang mid-drive motor from andy Kirby on youtube . Half the issue with the cheaper kits is the ingress of water into the electrics
hub drive is ok but its not good for anything else than flat stuff

I couldn't be arsed with another project so I have purchased a Cube with full suspension gen 4 bosch with the 750w battery. Your local government energy council are giving out loans and grants through the cycle to work scheme.

better to be riding fixing my health than creating another stress


That decathlon bike looks good but dont want to spend 2.5k on a bike........can buy a track day car for that 😁😁

Just want a bit of hill assist when i cant be arsed pedalling


skydivepaul - 13/4/20 at 04:41 PM

quote:
Originally posted by swanny
ive got a swytch kit.

definitely makes me use the bike more than i did.

some teething troubles, but the company sent new bits quite quickly.

it was less than a full electric so i treat it a bit like a kit car, might need the odd tweak here and there but genuinely love using it.

great passing MAMILs on big hills and watching them try to figure out how a fat lad on a massive hybrid eased psst them!


Haha great passing MAMILS , i have been known to wear tight clothes when out on my road bike .....Doh


skydivepaul - 13/4/20 at 04:43 PM

quote:
Originally posted by rf900rush
Yes I did this 2 years ago Apr 2018 to my mountain bike.
A bit of work needed doing to get the disk brake going, but i am sure any locost builder could do this.

I used a cheap-ish Chinese front hub with controller.
Like this 250w front option.
EBAY LINK
eBay Item

Luckily I have some batteries. Just a bit big. 12off 3.2V lithium at 25Amp hr

Used I a fair bit, mainly on the road.

No problems so far.


I was looking at these kits but for the rear wheel.
What is the bike like to ride when not using any power? Just the same as before fitting the kit?

Might have to do a bit of work on it as i have hydraulic disc brakes so the levers won't work for a start and not sure if the rear disc would be a straight fit


rf900rush - 13/4/20 at 07:22 PM

No, not like before. Just like it was way back when I had two kids being pull in a trailer.

Luckily never had to go far without the power.

I did try to keep the upgrade reversible, just in case.

Since this upgrade, I have always wanted to go the next step and do an electric motor bike.
First Idea was to get a moped, like I had in my younger days, only to find out they are selling between £1500 and £4000.
So that Idea has been shelved for now.
For some reason old bikes seem to go for decent money.


skydivepaul - 13/4/20 at 07:58 PM

quote:
Originally posted by rf900rush
No, not like before. Just like it was way back when I had two kids being pull in a trailer.

Luckily never had to go far without the power.

I did try to keep the upgrade reversible, just in case.

Since this upgrade, I have always wanted to go the next step and do an electric motor bike.
First Idea was to get a moped, like I had in my younger days, only to find out they are selling between £1500 and £4000.
So that Idea has been shelved for now.
For some reason old bikes seem to go for decent money.


That's my worry, most of the time i would ride without power, just maybe want a boost on the hills.

Some old bikes are now worth a few quid like some cars. Wish I'd kept a few in a lock up to cash in now !!


SPYDER - 14/4/20 at 08:42 AM

quote:
Originally posted by mangogrooveworkshop

...hub drive is ok but its not good for anything else than flat stuff




I'd agree with you up to a point. Hub drives, including most kits, usually feature standard QR type wheel axles which aren't really intended for serious off road use. A good rear hub motor will be plenty powerful enough though.
I built my first ebike up from a spare Kinesis frame and a Xiongda motor kit from China. I bought a high capacity battery from Insat International in the UK.
It's taken me round all my local forest trails including a Red route (albeit a reasonably tame one) and miles and miles up various glens, some of which are decidedly challenging.
It cost me about £600 in total (battery was 320) including an all-important brake upgrade. I was always conscious of it's limitations though so have "gifted" myself a Specialized Turbo Levo for my sixtieth birthday. The Kinesis is still used for local trips.

Take a look at Woosh bikes website. They have bikes for around a grand to suit most requirements and are often recommended on ebike forums.

Glen Banvie on the Atholl estate...



[img]http://


skydivepaul - 14/4/20 at 09:34 AM

quote:
Originally posted by SPYDER
quote:
Originally posted by mangogrooveworkshop

...hub drive is ok but its not good for anything else than flat stuff




I'd agree with you up to a point. Hub drives, including most kits, usually feature standard QR type wheel axles which aren't really intended for serious off road use. A good rear hub motor will be plenty powerful enough though.
I built my first ebike up from a spare Kinesis frame and a Xiongda motor kit from China. I bought a high capacity battery from Insat International in the UK.
It's taken me round all my local forest trails including a Red route (albeit a reasonably tame one) and miles and miles up various glens, some of which are decidedly challenging.
It cost me about £600 in total (battery was 320) including an all-important brake upgrade. I was always conscious of it's limitations though so have "gifted" myself a Specialized Turbo Levo for my sixtieth birthday. The Kinesis is still used for local trips.

Take a look at Woosh bikes website. They have bikes for around a grand to suit most requirements and are often recommended on ebike forums.

Glen Banvie on the Atholl estate...



[img]http://


Excellent, thanks for the info very helpful.
What is the wattage of your hub motor? what is it like to ride with out using any power? Like I mentioned in an earlier thread I want to keep the bike usable when not using any power, if that is possible.


SPYDER - 14/4/20 at 11:14 AM

^^^ The motor is rated at 250W and is marked as such but in common with most ebikes it's actual maximum is higher, in this case about 550W on a full battery.
Before anyone shouts "that's illegal then!" I can assure you that it's not. The 250W figure is a maximum continuous rating given by the manufacturer. The short term max achievable can be higher (and usually is).
My Turbo Levo is "rated" at 250W and came out of the showroom as such. It's actual maximum as shown by it's own software or third party phone app can be nearly 800W. Quite how long it could keep this up before the motor overheating and the bike reducing power I don't know. This is the battery power delivered figure so will be reduced a little by motor efficiency.
If the actual absolute max was 250W they wouldn't sell anywhere near as many bikes.
The Kinesis cuts out quite softly at the limit. The power reading on the display starts to reduce from 250 at about 15mph and fades away completely at about 17. There's no feeling of "switching off". It rides normally above the limit with zero resistance (but a heavy bike). Not all bikes are like this.
Bikes with the early Bosch Performance CX motor feel like pedalling through treacle above the limit.
Most Chinese hub motors, particularly the geared ones, behave quite well above the limit. Some of the "direct drive" types which have motors the size of dinner plates can be "draggy".
If you do buy a kit check whether it fits standard width dropouts. My Xiongda required the rear dropout to be widened by nearly 10mm.
I'd also recommend a "cassette" type sprocket fitting rather than the older "freewheel" type. Many Chinese kit feature the latter.

Turbo Levo up Glen Tilt.



SJ - 14/4/20 at 12:49 PM

I love the idea but TBH it just feels like cheating!

Also, I can't really see any practical benefits for me, as much as I'd like an electric bike I cycle mainly for fitness and can go way further than a battery would last for. Being able to go up hills easier would be counter productive.


skydivepaul - 14/4/20 at 01:44 PM

quote:
Originally posted by SJ
I love the idea but TBH it just feels like cheating!

Also, I can't really see any practical benefits for me, as much as I'd like an electric bike I cycle mainly for fitness and can go way further than a battery would last for. Being able to go up hills easier would be counter productive.


I used to think it was a bit cheating but i have a road bike that i will keep standard for long rides
I use my bike for fitness and pleasure but just sometimes if i cant really be motivated to get out on the bike i think the fact that it is electric assisted will make me use it more.


Copied from another website

Myth twelve: e-bikes are cheating

Fact: If you enjoy green living, having fun, getting out in the fresh air, exercise and saving money, then there really is no ‘cheating’ with an e-bike. An electric bike is simply a form of assistance that means that you won’t have to struggle uphill!

Electric bikes are actually encouraging people of all ages to get active and all they do is make the ride smoother and more enjoyable. It’s all a matter of how much assistance you desire on the day.


SJ - 14/4/20 at 01:56 PM

quote:

quote:
Originally posted by SJ
I love the idea but TBH it just feels like cheating!

Also, I can't really see any practical benefits for me, as much as I'd like an electric bike I cycle mainly for fitness and can go way further than a battery would last for. Being able to go up hills easier would be counter productive.


I used to think it was a bit cheating but i have a road bike that i will keep standard for long rides
I use my bike for fitness and pleasure but just sometimes if i cant really be motivated to get out on the bike i think the fact that it is electric assisted will make me use it more.


Copied from another website

Myth twelve: e-bikes are cheating

Fact: If you enjoy green living, having fun, getting out in the fresh air, exercise and saving money, then there really is no ‘cheating’ with an e-bike. An electric bike is simply a form of assistance that means that you won’t have to struggle uphill!

Electric bikes are actually encouraging people of all ages to get active and all they do is make the ride smoother and more enjoyable. It’s all a matter of how much assistance you desire on the day




Don't disagree at all. I'm sure they are also a lot of fun, particularly the less legal ones, though some are now basically electric mopeds. E-scooters are definitely a hoot! Just think for me I'd rather use my legs, but give me a few years maybe I'll change my mind!


coyoteboy - 14/4/20 at 05:49 PM

If I'm gonna get in my biking kit and get wet, I want to do it on my terms, not feel like I don't know what I've done exercise-wise. PErsonal choice, of course, but to me it is cheating. Sure it might make me get out more, but then I should just harden the hell up and get out anyway. It's just another excuse to waste hundreds when a couple of decades ago it wouldn't have crossed my mind.

That said, they can help lots of folk who just wouldn't ride otherwise, so they're a positive for that.


roadrunner - 16/4/20 at 08:05 AM

I ride quite often on the road anything up to 100 miles with an average of around 20mph. I use to commute 30 miles a day but now I have a scooter it's really hard getting my head around getting the bike out when the scooter is so cheap to run.
I have also considered an ebike just for commuting.
I could sell my Honda and convert my work bike. Was tempted with one of these Chinese kits but not sure if they would stand up to our weather all year round.
The standard legal ebikes are no good if they only assist up to 15 mph when for me that's a doddle.
An assisted 25 to 30mph average would be perfect and stop me from using petrol.


coyoteboy - 16/4/20 at 05:22 PM

Some of the kits online will give you 1hp at 28mph. That's pretty fun. But requires you to convert brakes on both sides, use their guff grips etc etc.


skydivepaul - 16/4/20 at 08:30 PM

ok so after much research and chatting with a few friends of friends and advice on here I've ordered the motor.
mid drive TSDZ2 500 watt, similar to bafang but works on a torque sensor rather than cadence and not as expensive.
I'll post some pics and let you know what it is like when finished.

Now to source the batteries........................................


SJ - 17/4/20 at 08:06 AM

Should be good fun! Are you planning to make your own battery pack or buy one?


skydivepaul - 17/4/20 at 09:09 AM

quote:
Originally posted by SJ
Should be good fun! Are you planning to make your own battery pack or buy one?


I have bought a 48v 10ah pack for this project
Next to do will be the wife's bike so may experiment with making a battery pack for hers


skydivepaul - 25/4/20 at 08:19 PM

Got the bike out today for it's first proper test ride

I went with a tsdz2 mid mount torque sensing motor with a 48v 10a battery
Wow it is great, still handles and feels like the bike and has not lost any of its feel. Just goes so much quicker!

Still get a good leg workout with the motor i can just go further and faster than before. Using level 1 or 2 mainly and even switching it off on the level at some points. Get to a steep hill, stick it turbo and power up at 15mph. With the tsdz2 you still have to put pedal effort in but it rewards you with some nice assistance.
My son borrowed the bike today and has ordered the same parts for me to fit out his bike.
Got a bit of tweaking to do, the cassette needs sorti.g as you can only use gears 5 to 9 as anything less than 5 and the chain jumps off the front ring as the chain line is too far out. Need to build the cassette with the right gears and spacers, something else new to me

Pic on Instagram
https://www.instagram.com/p/B_aq8cqADYU9gsLM_gSX3RbDtv8XrDp3HV_PW40/?igshid=gw571iummmau