Help and Advice required!

[pdarnett]

My local bike recycling charity have asked for some advice regarding converting a cargo recumbent bike to electric to enable them to carry bikes to the local college campus where normal vehicles aren't permitted.

The bike is this one http://www.bikeweb.org.uk/artbitz/adam_hart_davis1.jpg donated by their patron Adam Hart Davis. Needless to say, as a non profit organisation, they have very little money to spend, but they do have access to lots of bike bits, including a few junked powacycles I noticed in their workshop, so wondering if anything can be reused.

Any idea appreciated, I said I'd ask the "cloud" for suggestions!

They're a great little organisation, taking scrap bikes and refurbishing them to sell at very low cost (Usually £25 for a fully working bike) to students and low income families etc.

I took them 3 incomplete bikes this weekend that would have usually ended up on the tip and they'll be back on the road next week with some new owners.

So have a look at the picture (best one I could find I'm afraid) and see what you think, they only want about a 5 mile range but some hillclimbing assist. Probably SLA, battery wise, as they've got some powacycle packs.

 

[peerjay56]

My local bike recycling charity have asked for some advice regarding converting a cargo recumbent bike to electric to enable them to carry bikes to the local college campus where normal vehicles aren't permitted.

The bike is this one http://www.bikeweb.org.uk/artbitz/adam_hart_davis1.jpg donated by their patron Adam Hart Davis. Needless to say, as a non profit organisation, they have very little money to spend, but they do have access to lots of bike bits, including a few junked powacycles I noticed in their workshop, so wondering if anything can be reused.

Any idea appreciated, I said I'd ask the "cloud" for suggestions!

They're a great little organisation, taking scrap bikes and refurbishing them to sell at very low cost (Usually £25 for a fully working bike) to students and low income families etc.

I took them 3 incomplete bikes this weekend that would have usually ended up on the tip and they'll be back on the road next week with some new owners.

So have a look at the picture (best one I could find I'm afraid) and see what you think, they only want about a 5 mile range but some hillclimbing assist. Probably SLA, battery wise, as they've got some powacycle packs.

If they want to stay 'legal' they will have to convert it to a trike. Four wheeled vehicles are not catered for under EAPC rules (section 3, para 2), which is a b*mmer

 

[pdarnett]

Damn, that's a shame. Not even maybe a "pusher" trailer? i.e. not something that's permanently fixed to the bike?

 

[Deleted member 4366]

I'd be very surprised if the police would bother you. In the worst case, they'd tell you not to use it, so you'd have to take the electric stuff back off. It might be different if you ran someone over and injured them, though.

You might be able to register it as a Class 3 powered wheelchair. There's a couple of minor hoops to jump through and the speed limit is 8mph on the road and 4mph on the pavement for which you'd need some sort of control system.

 

[pdarnett]

I don't think that speed limit would be an issue, they just need some torque to get up hills and the campus is pretty hilly. I'm seeing some issues with the wheels if we want to go hub motor (which they have some old powacycle ones) unless they do some welding to provide support for both sides of the axle. maybe the back wheels with two controllers and somehow get them balanced on one throttle. That's probably where advice is needed!

 

[Deleted member 4366]

You only need one hub motor. Mount it on a couple of steel plates half-way between the crank and the rear sprocket along with it's gear cluster and rear derailleur. You need to copy the shape of the derailleur hanger on the right-side plate. The crank will then drive the motor just as if it were a back wheel. You need to mount a sprocket on the other side of the motor to drive a second chain to the sprocket on the back axle. The axle one needs twice the number of teeth as the motor one. You'll probably have to drill and tap the side of the motor to fit the sprocket. If you had a disc brake motor, you can use the disc fixing holes for it. You'll need a way of tensioning the rear chain. If it doesn't have adjustment at the drop-outs, you can make a tensioner out of a jockey wheel sprocket on an arm with a spring, or use a rear derailleur on a bracket.

This setup will give you a maximum assist speed of about 8 mph, but enough torque to climb very steep hills.

 

[trex]

a BBS01 crank drive would be easier to fit.

 

[Deleted member 4366]

a BBS01 crank drive would be easier to fit.

It's a charity. I don't believe they've had any scrap bikes donated with BBS01s attached.
Are you going to donate yours?

 

[peerjay56]

It's a charity. I don't believe they've had any scrap bikes donated with BBS01s attached.
Are you going to donate yours?

The theorising is great, but it's a charitable organisation; the trustees are legally liable for the actions of the charity, and any illegal activity could jeopardise it's charitable status, no matter how 'minor' it apears to be. Much better to go down the route of a towed trailer behind a powered bike, surely? Very different if we were talking about an individual responsible for his own actions.

 

[pdarnett]

D8veh nice suggestion, I have to have a look at how much clearance is underneath, but that sounds doable. I think they may have a welding bloke on the staff so fabricating some mounts shouldn't be too much of an issue. Shame the trailer bit doesn't have regular wheels or it'd get the two powacycle wheels on it they've got already!

On my other suggestion was to remove the recumbent front end and have a regular bike pulling the trailer?