Kit advice please

[Ridgelessbackhound]

Any advice gratefully considered please. I am looking for a conversion kit to fit on a Devinci Lifestyle cruiser style bike. I have some disabilities and want to ride very slowly, pedalling all the time and needing an extra boost for hills only. I mostly ride on bridle paths and similar terrain.
I don't think there is room to mount the battery on the seat post at the rear as I have the saddle very low.

I am looking for: easy to fit, reliable battery, lightweight, long slow assistance which I can control, reasonable price.
It has taken ages to find a bike frame which suits my needs and I now want to explore further afield. I think a conversion is the best bet as the only similar frame I can find on an ebike is the Pedego cruiser which looks ideal but too expensive, although I would reconsider if anyone knows of an alternative cruiser type ebike.

 

[Alan Quay]

Hi,

I think you should post a pic of the bike you want to convert, so we can all have a look.

Important factors will be:
Forks- steel or ally?
Brakes.
Drivetrain.
Rack mounting points.

I have converted cruisers before, they are lots of fun.

 

[Deleted member 4366]

A sideways loading bottle battery should fit in your frame. I think you'll struggle with a normal one. If you're not going to have a rack battery, you'll be limited on power to 15 amps at 36V and a 250w motor. Have a look at the BMSBattery website.

 

[Ridgelessbackhound]

Have tried to attach photo, not really sure how to do it on an iPad, hope it comes out ok. This is the type of bike though mine has a rear pannier rack and the seat so low that there is very little space between the seat and the rack. It is a bit heavy at the back end and light at the front so I am thinking that it might be better not to add any more weight at the back.
No idea about the other things, will try to find out. ( as you will have gathered I am no cyclist just a person who likes to be outdoors with a dog but can no longer walk very far.)
Will also look at the sideways bottle battery, thanks both for your replies so far.

 

[Ridgelessbackhound]

http://www.devinci.com/bikes/bike_437_print

This is the link to the page with all the specs on. Not sure what it all means but hopefully it covers the points Mike has raised.

 

[jackhandy]

I think you're right not to opt for a rack battery on that frame: As you say, the rider's weight is already making it back-heavy.

I nipped out of a sideroad a bit smartish t'other day and, with the motor giving max. torque & me pumping hard, the front lifted enough while turning to dump me in the road.
Most inelegant.

 

[Ridgelessbackhound]

Thanks, I think your experience confirms that I am looking at a battery to fit in the area of the bottle carrier and also a front wheel motor not rear. Two that look like possibilities are Cyclotricity which has the price advantage and Conv e which appears to be the simplest to fit and therefore to remove if I don't get on well with it. However there seems to be so many variables to consider that I am finding it very hard to choose. It would be easier if I could try some out but as there are very few cruiser bikes about I will eventually have to take a chance and make a decision!

 

[Deleted member 4366]

To make it more complicated, you also need to consider the RPM of the motor, which will affect the efficiency and speed. You have to decide on the speed you want to go, and then choose a motor with the correct RPM that also has enough torque to provide the speed and the hill-climbing you need. These things are much more important than the position of the motor and battery unless you go for a very big battery and motor.

 

[Alan Quay]

So it looks like:
26" wheels
Steel fork
V brakes
Deraileurs

I agree, front hub motor is probably the best bet.

201 rpm is the norm if you want to go about 18mph (ish) top speed.

The challenge will be getting a battery into that frame triangle, as it looks very small.

Could you measure the space and post a drawing of the dimensions? Perhaps someone will be able to confirm what battery options you have.

The other options might be a custom battery pack, or battery on the rear carrier.

 

[Deleted member 4366]

These are the dimensions of the sideways fitting bottle battery. You can make a cardboard template to see if it fits, but don't forget that yo can only run a 15 amp controller from one, so not so good for heavyweights and/or serious climbing.

 

[Ridgelessbackhound]

Thankyou so much everyone for all your input, things are beginning to clarify in my head. I had no idea about any of this. I will post some frame measurements later.
Regarding speed etc, I really am only wanting some additional extra assistance to get up hills which are generally longish if on the road or maybe only a few metres up and down on a bridle track . I am not trying to get anywhere quickly, just to spend a long time meandering about in the countryside, mostly at dog speed.
This probably sounds strange to real cyclists but to explain: I was a lifelong horse rider and keen walker but gathering disabilities have stopped me from doing either. Following surgery a year ago I have been trundling about on a mobility scooter which saved my sanity but gives no exercise. I have now been working in the gym and feel ready to start cycling but definitely need a boost for hills as I am not strong enough to pedal up them and can't walk up them either as my foot is in poor condition. However I do want to be pedalling continuously. So, we are looking at slow haulage rather than sprinting anywhere.

 

[Ridgelessbackhound]

Here is a sketch, not to scale, showing the internal measurements of the area inside the frame in mm.

 

[Ridgelessbackhound]

Second attempt, hope this one looks better.

 

[Ridgelessbackhound]

D8veh, the sideways bottle battery fits the space, provided it is not too fat to
Interfere with the pedals, although from the rest of your post it sounds as if it might not give the assistance I am looking for.
I do have fairly strong legs and can pedal unassisted partway up most of the hills around here, the problem I think is that i am always approaching a hill from a very slow speed so just fizzle out before the top.

 

[Deleted member 4366]

How heavy are you? A 10aH bottle battery can give enough power, but it depends what motor you want. The Bafang BBS01 crank-drive kit, should give you what you want, or a 180 rpm hub-motor, or even the 2-speed Xiongda kit.

 

[Ridgelessbackhound]

Currently 11.5 stones and on the way down (slowly)

 

[Deleted member 4366]

Currently 11.5 stones and on the way down (slowly)

In that case any motor will be powerful enough. You don't need a high torque motor and high powered battery. This sideways mounting battery should be good. You only have to check that the mounting holes willline up, which they should:

http://www.bmsbattery.com/36v/571-bottle-ebike-battery.html

You can get your motor-wheel or BBS01 from there too and everything else.

 

[Ridgelessbackhound]

The battery looks ideal. The site appears to sell all the bits separately, which is beyond me. Do you know if there is there anywhere that I could take the bike to have the whole lot properly installed?

 

[Deleted member 4366]

Do you know if there is there anywhere that I could take the bike to have the whole lot properly installed?

It might help if you said where you are!

 

[Ridgelessbackhound]

Between Reading and Oxford