Mantis Trike

[Joe.B]

My wife and I are considering buying a second trike with the idea of possibly converting either it or our existing ICE Sprint into an electricly assisted bike.
The second trike needs to be cheep, spending the same amount of money on another trike as we spent on the ICE is not an option.
To this end I've been looking for secondhand trikes, and found nothing, except this:

http://www.ebay.co.uk/itm/ws/eBayISAPI. ... 0409885720

Does anybody know of or have any experience of Mantis trikes? I'm not really sure weather to go for one of these or wait for something like a Trice or Catrike to come up secondhand.

Cheers
JB

[[XAP]Bob]

Readily admit that they are TW Bents - which are a reasonably well known manufacturer.
SEE viewtopic.php?f=5&t=37773

The 81 speed will increase the gearing range, but not by a huge amount - You'll have plenty of duplicated gears.

How are you going to go electric?
I'm planning to use a jackshaft (Actually aiming to use a SA 3spd as the jackshaft) and use the motor to chain drive the rear chain. Then the motor can operate without the pedals, the front is simple, you can change gears at a standstill...

In terms of a basic design it looks OK - no obvious faults...

[Joe.B]

I'm not sure how to do the electic convertion yet Bob. Or even weather to buy another trike or to convert the existing Sprint to an ebike.
My reason for wanting an electiric is to get my wife riding again. We moved from Gosport to Plymouth a few months ago and since being here she as hardly been out on her trike. She as asthma and is unable to cope with riding in such a hilly part of the UK, especially with the little guy and various bags of shopping in the trailer.
If I convert her Sprint I think the best option may be a 500w rear hub motor, she wants to be able to ride completely under her own power when in less difficult parts of the world so having the hub motor enables me to simply swap the rear wheel for a conventional one and remove the battery to make it a normal trike again.
A second trike provides the advantage of using other types of drive but still having the sprint as a 'pure' human power trike.
Another possibility are the Atomic Zomie bikes, I've a good pal up north who could fabricate the frame in steel or aluminium leaving me to finish the build.

[[XAP]Bob]

Why don't I have friends like that.

[Joe.B]

I've not asked him yet, but he does keep saying that he wants to build one for himself

[byegad]

Careful. 500W makes it a motor vehicle subject to all the C&U regulations which it will fail. The limit is 250W for a trike IIRC. Try subscribing to Electric Bike, published by Peter Eland, or AtoB. Both deal with electric bikes, big give away in the first title , and will steer you right.

[Phil_Lee]

The current Electrically assisted pedal cycle regulations can be found Here. It's surprisingly readable for a legislative document
There was a recent consultation on changes to them (with the aim of bring us into line with the rest of the EU) so they may change in the reasonably near future.

[Cunobelin]

Speak too ICE

I had the privilege of knowing Ron Beams, who had a number of Trices made by them with power.

I would have reservations about the Mantis though, ground clearance is an issue on trikes, and the apparent derailleur below the boom is vulnerable.

[Joe.B]

Thanks for all the replies folks, I am going to get in-touch with ICE, I figure they will know a thing or two about making their trikes electric.

I'd better be careful about the cycle regulations, while I would'nt want either the wife or I to get into bother we do need a good amount of power for getting the trike & weighty trailer over the local hills.

[Joe.B]

After much internet research it seems that the best rear wheels based motors are the Binox & Heinzmann systems, both however are very expensive. The best price I've found yet is a Bionx 350watt system
http://www.bikesonline.com/bionx-pl-350 ... spokes.htm
The advantage of the Bionx is that in its lower power setting it will give just enough push to compensate the baby-trailer and luggage while giving a 60 odd mile range, great for club rides. This allows the higher power modes to be reserved for the big hills & trailers full of shopping.
Another advantage is that the motor is direct drive, no gears. This means that if the battery is flat of the system is off the resistance encountered should be not much greater than a hub dynamo. (hopefully).
The batteries are terribly expensive but with a 800 cycle life there will be a good few years between replacements.
I don't know weather this motor would let me keep the nine speed transmission or weather I'd have to switch to seven speed.
I still need to speak to ICE and see if they have any reconmendations.

[byegad]

Fun8 or 8fun motors (Can't remember the name.) are cheaper. I know a couple who fitted them to their ICE trikes and love them, and they are legal!

Seriously for bigger hills you need more batteries and a crank drive so the motor is powering through the chain and so geared down on hills. Then you don't need to run the risk of getting done for C&U violations by using a bigger direct drive motor. Some of those carry big fines, vehicles outside the electric bike regs' limits need insurance, so you can be done for 'driving' without insurance, lights and other safety equipment is subject to the car type rules, it will need a number plate and you need a Vehicle Excise Disc, irrelevant that it would be £0 as it is an electric vehicle, as well as being guilty of riding a vehicle not 'type approved' on the road.

[[XAP]Bob]

In typical loophole fashion - what would a powered trailer do to the rules?

A couple of hundred Watt hub motors as the wheels of a trailer with batteries in the trailer base - you can't call it part of the vehicle, can you?

[GeoffL]

In typical loophole fashion - what would a powered trailer do to the rules?

A couple of hundred Watt hub motors as the wheels of a trailer with batteries in the trailer base - you can't call it part of the vehicle, can you?

Unfortunately, yes. Worse, it would probably require either a B+E or even C+E licence to 'drive' it. However, that's all academic because you wouldn't get it past the Construction and Use regs anyway!

[harveyyboyy]

I want to build a diesel driven trailer for pushing my tandem, single bike and bike trailers. Could I be pulled over by prosecuted even if I notified the dvlc of the type of vehicle and the power of the engine?

[[XAP]Bob]

referred to in Regulation 3

The requirements

above are that the vehicle shall:—

(a) have a kerbside weight not exceeding—

(i) in the case of a bicycle, other than a tandem bicycle, 40 kilograms, and

in the case of a tandem bicycle and a tricycle, 60 kilograms;



(ii)



(b) be fitted with pedals by means of which it is capable of being propelled; and

(c) be fitted with no motor other than an electric motor which—

(i) has a continuous rated output which, when installed in the vehicle with the nominal voltage supplied, does not exceed—

(A) in the case of a bicycle, other than a tandem bicycle, 0.2 kilowatts,

(B) in the case of a tandem bicycle and a tricycle, 0.25 kilowatts; and

(ii) cannot propel the vehicle when it is travelling at more than 15 miles per hour.