Best place for battery for e bike conversion

[raydaffurn]

Looking at building 500/1000w e bike conversion kit.

Seen this kit on ebay reviews look good:

https://www.ebay.co.uk/itm/26-1000W-Electric-Bicycle-Rear-Wheel-Motor-Conversion-Kit-LCD-Meter-E-Bike-Hub/122638459582?epid=1185924259&hash=item1c8dd262be:g:3M4AAOSw66pZirTd

Says min battery needed is 48v 11.6ah - where would be best to pick one of these up? Idealy im looking for one that mounts on the frame rather than on the back. Still to buy a bike which i reckon could get a half decent used one for £80/100 and trying to keep the build under £400/450.

Also open to suggestions if anyone knows any other decent kits.

 

[Benjahmin]

Hi Ray,
Best get a bike first, then you can get specific help.
Do you realise that the kit you've linked to is a direct drive motor? These are fine for flat roads at higher speeds. At lower speeds they are inefficient and throw a fair percentage of your battery power away as heat. This low speed quirk makes them poor hill climbers and likely to stall or even burn out.
So depends how and where you want to use the bike.

 

[Deleted member 4366]

It's not the size or capacity of the battery that counts, it's how much current it can give. You need one that can provide 1000w, which means around 25 to 30 amps continuously. That eliminates all the cheap batteries. An 11.6Ah battery will give probably less than 10Ah when used with a motor like that, so, at say 30 amps, it would last about 20 minutes. You should expect a range of between 10 and 20 miles depending how much power you use. If you want more range than that, you should be thinking about a bigger battery.

In case you don't know, those motors are extremely heavy and don't free-wheel too well, so riding without power won't be very nice.

Nearly everyone that I know that fitted one of those motors soon swapped it for a smaller geared motor.

Edit: I've just seen that it says 26A on the controller.

Be careful of the reviews. Most people are full of euphoria after riding an electric bike for the first time. They can't wait to come back and tell the world about their great experience. After some time, they start to realise all the shortcomings, but it's very rare that they ever come back and tell us about them. More likely, the bike and the fantastic kit are confined to the shed to make convenient anchorages for spider webs.

 

[raydaffurn]

Ok not got a bike yet thought it would be best to get a kit then get s bike.

Is my budget realistic say £400 max for kit and battery?

Doesn’t need to be 1000w happy with 20mph ish on flat so would I best look at 250-500w, trrrain will be mainly flat but will have some hills.

Any vendors or web sites i should be loking at?

Cheers for help so far.

 

[Deleted member 4366]

£400 is possible. You can get quite good kits from Ebay for under £200, which leaves just over £200 for the battery ad other stuff.

It might be an idea to show us a photo of the bike you intend to get, then we can advise you which kit you need. Also, tell us how heavy you are, what hills you have and how far you want to go,

 

[raydaffurn]

£400 is possible. You can get quite good kits from Ebay for under £200, which leaves just over £200 for the battery ad other stuff.

It might be an idea to show us a photo of the bike you intend to get, then we can advise you which kit you need. Also, tell us how heavy you are, what hills you have and how far you want to go,

Haven’t got bike yet as was thinking get kit first that way I can pick up bike to suit.

Weight 9 stone so very light.

To be honest it’s mainly flat where I stay there’s a few hills but mainly going to be used on flat.

Distance we’ll be happy with charging say every 15-20 mile but obviously if I can get more then all the better.

 

[Benjahmin]

For a featherweight like yourself, almost any 250w geared hub will suit fine. If you go for a 36v motor but run it from a 48v battery you will get the speed you want.
Again - best get the bike first because some dropouts can differ. Also frame geometry can be an issue sometimes.

 

[raydaffurn]

D8veh you got any links to the eBay kits you said was good so I know what to look for? Typed in geared but nothing comes up.

And by geared do you mean a wheel that has the 7/8 cogs that allow you to change gears on a normal bike?

 

[Deleted member 4366]

https://www.ebay.co.uk/itm/36V350W-Electrical-bicycle-E-bike-Hub-Motor-Conversion-kit-Rear-wheel-26/222254716621?hash=item33bf69d6cd:g:byUAAOSwQwZaXvGL

Check out his other items. He has batteries too. Get yourself a cheap used MTB with a triangle frame as the cheapest solution, or, if you want speed, get a hybrid type bike with 700c wheels and fit one of his 700c kits. Back wheel motor is always best,

 

[Benjahmin]

And by geared do you mean a wheel that has the 7/8 cogs that allow you to change gears on a normal bike?

No the motor itself has internal gearing, normally around a 5:1 ratio. This means that there is a clutch which disengages when the power is off, giving little or no resistance when coasting. Unlike the direct drives which are always engaged and act like a generator/drag when cycling without power. Normal bike gearing will fit onto the motor D8veh linked. That looks like a good kit, you get all you need(including tools) except the battery.

 

[raydaffurn]

Ok contacted seller he gave me link to following with battery:

https://www.ebay.co.uk/itm/302623660521

My only concern is it says thumb throttle available to 6kph - does this mean after 6 it’s only pedal assist - was hoping to get a kit that could be used just on electric only?

Looks to be suitable for v or disc brakes I think waiting on seller confirming though.

Again cheers for the help very much appreciated.

 

[Nealh]

Ok contacted seller he gave me link to following with battery:

https://www.ebay.co.uk/itm/302623660521

My only concern is it says thumb throttle available to 6kph - does this mean after 6 it’s only pedal assist - was hoping to get a kit that could be used just on electric only?

Looks to be suitable for v or disc brakes I think waiting on seller confirming though.

Again cheers for the help very much appreciated.

By law the thumb throttle is set and supplied to 6km/h operation but with the supplied KT controller and via the lcd3 you can change the throttle to full speed mode using the parameter settings.
All the new KT controller/LCD3 have these options.

 

[Deleted member 4366]

The pictures and motor diagram both show disc fixings.

 

[raydaffurn]

Cheers for the help I’ll get an order placed

 

[Flyingppg]

Ok contacted seller he gave me link to following with battery:

https://www.ebay.co.uk/itm/302623660521

My only concern is it says thumb throttle available to 6kph - does this mean after 6 it’s only pedal assist - was hoping to get a kit that could be used just on electric only?

Looks to be suitable for v or disc brakes I think waiting on seller confirming though.

Again cheers for the help very much appreciated.

I have this kit and we are very pleased with it. However the supplied controller is limited to 15a peak load (from memory) and this seller doesn't seem to offer anything other than a 36v battery so not sure what happens at 48v?

The wheel is is also available in either screw on free wheel or cassette (cst) versions. Check carefully which one is which and make sure you order the right one for you. The wheels certainly support both disc and v brakes. We like the rack battery because we also have paniers for shopping, but maybe you are 20 years younger than me.

I agree with others that a geared motor is best. Much lighter, much more torque on hills and the planet gearing has a free wheel built in so no drag when off motor. Don't look at motor watts alone.

 

[Nealh]

48v will fry the controller as the main in rush cap is only 50v.
The hub is quite fastly wound at about 270/280rpm or 23mph in a 700c rim.
At 48v the motor has far more torque/acceleration and if needed more speed ( hub rpm will inc from circa 270/280 to approx 335/350 rpm). With a 20a controller peak watts
output I saw was 890w in PAS5. PAS 4 max I saw was about 580/600w then a big leap in PAS 5 to 890w.

 

[footpump]

i have similar kit but from elife shop, not fitted yet.

but the link to kit+battery the controller is inside the battery case so an even neater self build

 

[raydaffurn]

Ok was planning on buying kit

https://www.ebay.co.uk/itm/302623660521

Got a bike was advertised as 24 speed (3x8) went and double Checked and it’s 21 speed (3x7) seller says can’t use it and I can’t get a 7 cassette elsewhere to fit to his kit.

Any other kits that are like this but fit 7 cassette otherwise I need to go get another bike?

 

[Deleted member 4366]

Do you know the difference between cassette (free-hub) wheels and free-wheel wheels? 7 speed is normally free-wheel. 8 speed and more is normally cassette. The motor in that kit is a cassette one. You need a free-wheel one sold by the same seller, but first you need to confirm your wheel type.

 

[raydaffurn]

No didn’t know about cassette vs freewheel I thought cassette was the cogs, thought they were all same.

I’ve had a look online and by the looks of it if the inner hole is rounded it’s freewheel and if it’s splined then it’s cassette, that right.

Can’t check bike till night but this is same bike, Saracen tt:

http://www.bikes2udirect.com/B3178.html