Help with my first conversion kit.

TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0
Hi All

I'm wanting to buy a conversion kit to fit to an old steel bike I have. I have a 4 mile commute to work with no hills. I'm in the UK and hold a full car and motorcycle licence. Is the kit in the link below worth buying? I'm new to electric conversion but not new to cycling, I'm an area co ordinator for a worldwide cycling community but our forum does not have an electric section.

This is the kit I have found to be, I think, best suited for me:

https://kirbebike.com/products/250w-ebike-conversion-kit?variant=43365620678809

I also have a few questions:

1. As I'm used to riding a Yamaha R1 and KTM 690 Duke can I go for a larger 750w motor or similar and be legal in the UK?
2. If I buy the kit above should I buy it without a battery and buy a 48v battery seperately? If so where can I buy such a battery in the UK?

Thanks in advance :)

Trebz
 

matthewslack

Esteemed Pedelecer
Nov 26, 2021
1,627
1,207
For a four mile flat commute you really don't need to be looking beyond standard 250W hub motor kits.

750W is a moped, not legal under pedelec / EPAC / EN15194 rules. Pedelecs are bicycles in law, your motorbike licence makes no difference.

Throttle (kit linked has throttle and a warning about off road use only) you need to read up on. The rules for user fitted vs manufacturer fitted have some differences.
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
3,679
2,675
Winchester
As matthewslack says, the 750w would not be not legal as a pedelec. Just to clarify:
It could be legal as an s-pedelec/moped. You'd need to get it approved to ride on the road, then arrange insurance, registration, license plate etc. And you couldn't legally ride it off road in any publicly accessible space such as bridleways, cycle path, canal paths, etc.

I assume if you went 750w it wouldn't be a front wheel conversion?
 

Benjahmin

Esteemed Pedelecer
Nov 10, 2014
2,484
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West Wales
For a 750w motor to be street legal you would have to have it SVA tested, fit a number plate, compliant lights, have it insured, wear a full motorbike helmet and not ride on cycle paths. Worth it?
On the face of it the kit you've linked looks to be fair price, as it includes a battery perhaps on the cheap side.
So I would ask a few questions:
What cells are in the battery?
What is the maximum output current of the battery?
What make and rating is the controller?
The battery maximum amperage output needs to be greater than (10-25%) the maximum current draw of the controller for battery health.
As a cyclist a 250w motor will be plenty for you. The 250w rating is merely a rating at which the motor willnot overheat in continuous use. It is not a limit. The controller is likely to be at least 15A which, at a nominal voltage of 36v, will give you a maximum of 540w assist, plus your own input. Ask, what can a sports cyclist develop on a hill climb?
Welcome to the fascinating world of electrickery biking!
 
Last edited:

TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0
For a 750w motor to be street legal you would have to have it SVA tested, fit a number plate, compliant lights, have it insured, wear a full motorbike helmet and not ride on cycle paths. Worth it?
On the face of it the kit you've linked looks to be fair price, as it includes a battery perhaps on the cheap side.
So I would ask a few questions:
What cells are in the battery?
What is the maximum output current of the battery?
What make and rating is the controller?
The battery maximum amperage output needs to be greater than (10-25%) the maximum current draw of the controller for battery health.
As a cyclist a 250w motor will be plenty for you. The 250w rating is merely a rating at which the motor willnot overheat in continuous use. It is not a limit. The controller is likely to be at least 15A which, at a nominal voltage of 36v, will give you a maximum of 540w assist, plus your own input. Ask, what can a sports cyclist develop on a hill climb?
Welcome to the fascinating world of electrickery biking!
Can point me in the direction of the door heheheheheh ;-)
 

AGS

Esteemed Pedelecer
Feb 12, 2023
466
141
Those Kirby front wheel kits are a great alternative to the Swytch kit for a fuss free quick installation.

Also if you have hydraulic brakes you can’t use the supplied brake levers with the motor cut off switches. It’s debatable if you need them anyway at 250 watts, but some people find them useful.

You should do some homework first before jumping in and see if an alternative better suits your needs.

Have you considered a mid drive or rear wheel kit? They all have their pros and cons.
 
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TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0
This kit is not legal, but can be if you restrict throttle to walk assist and speed to 25km/h.

48V batteries are legal.

This kit is very expensive.

Edit:
48V battery they sell is HUGE!

Not sure why they market throttle as advanced safety feature. They made me laugh.
Ok thanks, all points noted. Does anyone have a link to a 250w kit that is less expensive. I'm wanting to buy something this weekend if possible. I've been looking around for days and I'm working off YouTube recommendations at the moment.
 

TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0
Those Kirby front wheel kits are a great alternative to the Swytch kit for a fuss free quick installation.

Also if you have hydraulic brakes you can’t use the supplied brake levers with the motor cut off switches. It’s debatable if you need them anyway at 250 watts, but some people find them useful.

You should do some homework first before jumping in and see if an alternative better suits your needs.

Have you considered a mid drive or rear wheel kit? They all have their pros and cons.
I'm looking at a front wheel kit as it's the simplest installation in my opinion. The kit will be fitted to my steel 1988 Specialized Rockhopper with standard Cantilever front and rear U-Brake, more than enough to stop me at lower speeds. I used a 1988 Rockhopper all through the late 80's up to the mid 90's in the UK. riding the North Yorkshire Moors, Lake District and Dalby Forest etc etc. I'm sure I'll be ok on my daily flat commute :) I just need a little help as I don't want to get to the office all sweaty and have to shower / change before I start work. I recently lost my car and have been using a 1965 Moulton Deluxe to get to work but I just got myself a new job with a longer ride to work. The Moulton will be restored or sold and I'll be going back to my original commuter bike (The Rockhopper) but with electric assist. The Rockhopper is ready to go with mudguards, rear rack etc etc so all I need is a front wheel kit.
 

AGS

Esteemed Pedelecer
Feb 12, 2023
466
141
Woosh kits are similarly priced.


If you want to save money you can buy all of the parts from China. Delivery will be longer and you will need to understand what you are ordering and how to assemble the thing properly.

Here is a link to Topbike kit where a few experienced people on here order their parts from.

 

Az.

Esteemed Pedelecer
Apr 27, 2022
1,266
570
Plymouth

I advice against importing things from China. Especially batteries.
 

TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0
Woosh kits are similarly priced.


If you want to save money you can buy all of the parts from China. Delivery will be longer and you will need to understand what you are ordering and how to assemble the thing properly.

Here is a link to Topbike kit where a few experienced people on here order their parts from.

Link appreciated but I'm not experienced enough to buy the items seperately. I'd be happier with a 'Full Kit' purchase like the one in the link i posted.
 

AGS

Esteemed Pedelecer
Feb 12, 2023
466
141
UK suppliers import everything from China. You have to pay their mark up, but they have done all of the leg work for you and you get warranty that means something to lessen your risk. Also they keep stock so delivery is quicker.
 
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Az.

Esteemed Pedelecer
Apr 27, 2022
1,266
570
Plymouth
Link appreciated but I'm not experienced enough to buy the items seperately. I'd be happier with a 'Full Kit' purchase like the one in the link i posted.
Woosh sell full kits. Prices higher than average, but UK based company and excellent customer service.
 

AGS

Esteemed Pedelecer
Feb 12, 2023
466
141
Woosh are similar to Kirby. They will both supply you with a full kit from the UK. Both of them are regular posters on here and have a good reputation.
 

matthewslack

Esteemed Pedelecer
Nov 26, 2021
1,627
1,207
Like building a house....you can have a good house, a low cost house and a quick house, but you can only have two of those three.

If you want quick, good with excellent customer service and technical assistance, maybe pay the bit extra and talk to Woosh today.

Disclaimer: I am not a Woosh customer, just giving the benefit of two years reading this forum.
 

sjpt

Esteemed Pedelecer
Jun 8, 2018
3,679
2,675
Winchester
The kit is sold as 36v. If you use a 48v motor you may need to change the controller and possibly the display.
If you are lucky they will already be OK for 48v, but very likely not.
 

TrebzUK

Finding my (electric) wheels
Jul 31, 2019
18
0