My new 31 year old "e-bike" !

[morphix]

Hi all,

Look what I just picked up...

I've decided to try and turn a C5 into a C6 by bringing it into the 21st century with a new front wheel hub motor conversion, and by putting a ton of gadgets and technology on the front console ;-)

This beast weighs 45kg with the original 12V 36Ah lead acid battery weighing 15kg by itself!!

The C5 is a terrible hill climber and cannot even manage a 6% incline without pedaling, the motors regularly overheat and the design is absolutely terrible! However it was 1985 and they were limited in battery options and electronics were far more primitive than todays modern controllers.

I'm undecided whether to leave the original motor in (alongside the front-hub motor) and fit a new 12V lead acid battery so it provides extra hill climbing power, or whether to strip all the old stuff out and attempt to do something with the back axle which rotates and has a fixed gear system and a very long chain to the pedals chain wheel at the front.

I'd welcome any suggestions or ideas!

I have the original service manual and a lot of technical docs from the original designers, which I will upload if anyone is interested in the design of the C5..

Paul
P.S. For those wondering where I disappeared to:
http://www.pedelecs.co.uk/forum/threads/the-lost-sheep-returns.24043/

 

[Gubbins]

Wow!

 

[morphix]

For those interested in the design and what's underneath that futuristic looking shell.....

Credits: "Chas" aka C5Restorer from C5alive Club and C5alive for the circuit schematics.

Chas has stripped down and restored many C5's, and here it shows how quickly it can be done in a video he made..

10 surprising facts about the C5...

#1 Lotus designed and manufactured the chassis and also assisted on the body design which was design tested in a wind tunnel for aerodynamics.

#2 Hoover (yes the people who make vacuums) assembled and serviced the C5's from a factory in Wales. This created a persistent myth that the motor in the C5 was a washing machine motor, but it was specially designed by a Philips Italian subsidiary for the C5.

#3 Only around 17,000 C5's made it off the production line, and of those only around 12,000 were ever sold. Sinclair had predicted sales of 200,000 units in the first year, increasing year on year.

#4 Some of the first customers of the C5 were the rich and famous of the day. Elton John ordered two and two more were purchased by Buckingham Palace for the young princes William and Harry.

#5 By the end of 1985, retailers such as Comet were selling the C5's for just £149 each, instead of £399 (about £1,000 in today's money).

#6 A northern company purchased the remaining 2,000 or so C5 stock from the company's receivers for just £75 each. Within a year it had re-sold most of the C5 stock for a huge profit to wealthy overseas customers. Some were exported to the US as golf buggies, but most went to an Arab oil state and were marketed as toy cars, they sold for around £499 each.

#7 A C5 enthusiast known as "Electric Dave" created the world record for the fastest time an electric vehicle has ever climbed the Brookland's Test Hill (very steep hill used to test new cars) in around 6 seconds, using a heavily modified C5, he dubbed the C-5000. It was capable of rapid acceleration and speeds over 60mph.

#8 Of the more unusual C5 mods...three stand out, one C5 owner fitted a gas turbine engine into his C5, whilst another fitted a jet engine, and another made a C5 monster 5ft wheel version which was successfully entered into an American monster trucks competition.

#9 Until recently, the C5 despite being a spectacular commercial failure was still the biggest selling electric vehicle in UK automotive history.

#10 Sir Clive Sinclair spent £23 million pounds developing the C5, and invested £7 million of his own personal money. He was already making plans for a larger version of the C5 pre-production, the C10 (which looks remarkably similar to the modern Renault Twizy), a full fledged electric car which was due to be launched quite soon after the C5.

 

[morphix]

Wow!

You want to keep me convert it Phil and have a ride after? ;-) I think I need all the help I can get with this one!!

 

[Gubbins]

You want to keep me convert it Phil and have a ride after? ;-) I think I need all the help I can get with this one!!

Hi mate.
Thanks for the offer but I dont have the skills to be of much help and am well tied up with family issues for the foreseeable future .
Great idea though and good luck with it.

 

[morphix]

Oh I meant just via the forum Phil! Sending your ideas and suggestions etc. You're a long way off for a ride unfortunately, I'm right down in the Midlands!

 

[Kenny]

Welcome back Paul and quite a return.......Great project!

 

[Gubbins]

Oh I meant just via the forum Phil! Sending your ideas and suggestions etc.

Ah.
There are some really knowledgeable and helpful people on here and I am sure that advice will be impressive and freely given..... even if you fit a d***le

 

[Deleted member 4366]

Welcome back from the dead Morphix. Are you OK now? I guess you must be.

I know what I'd so with that C5: Make a new nracket that holds the motor. The idea is to make one 135mm wide with dropouts like on a normal bicycle. You need the one on the right side to have the additional hole or hanger for a derailleur. You then fit a normal geared hub-motor and fit a sprocket to the disc brake mount so that the motor works like a motorised jackshaft with gears and freewheel on the right side. That arrangement gives you gears as well as a more powerful free-wheeling motor. You can change the final gear ratio by the size of the sprocket on the disc mount, though a normal 328 rpm motor with a 1:1 final reduction would probably be about right.

 

[morphix]

Welcome back from the dead Morphix. Are you OK now? I guess you must be.

I know what I'd so with that C5: Make a new nracket that holds the motor. The idea is to make one 135mm wide with dropouts like on a normal bicycle. You need the one on the right side to have the additional hole or hanger for a derailleur. You then fit a normal geared hub-motor and fit a sprocket to the disc brake mount so that the motor works like a motorised jackshaft with gears and freewheel on the right side. That arrangement gives you gears as well as a more powerful free-wheeling motor. You can change the final gear ratio by the size of the sprocket on the disc mount, though a normal 328 rpm motor with a 1:1 final reduction would probably be about right.

Hi d8vh great to see a familiar name and you still have the same avatar! I hope you're well yourself.

As for me, I'm sort-of ok! I feel a lot better than 6-8 months ago. However my brain isn't as sharp as it once was :-/ Maybe it will improve, they do say the brain is like a muscle the more you use it, neuroplasticity etc.

I like your thinking on the C5 updating. That sounds like a good approach. Anything rear-drive that involves replacing the axle will be very challenging/difficult for me though as I have very limited ability when it comes to anything mechanical! I suspect with your skills and equipment, it would be easy peasy for you to do that. I've seen some lovely mods done which similar to what you describe, lovely work, all the back end re-engineered with a big plate and motor mountings drilled and bolted down.

When it comes to improving the gears, one of the most common mods is to fit the Sturmey Archer hub 3-speed gears, as used on Raleigh Chopper to avoid using a derailleur. I think that is more to do with keeping the C5 as original looking as possible though. I used to ride a Raleigh Chopper as a boy and I remember the gearing range was lovely on them. 3rd gear provided a tremendous amount of torque for a kiddie bicycle. I'm not sure that would quite work though on a C5 due to the sheer weight of the thing, the long chain and oversized pedals etc, it doesn't look terrible efficient does it?

These C5 club owners are fanatical about keeping everything original.
I have no problem though with changing anything and everything if it results in a more functional and usable C5, it's just the doing-it part will be challenging.

One major problem with the C5 is the very limited and wide steering angle. Do you think this would be a problem with a front-hub motor approach, possibly dangerous even? It's a pity the handlebar is where it is, that's the reason the steering sucks so bad. And it's annoying because if you look at the chassis there's a steering column coming right off it. You could put a kind of forward handlebar on a C5 to improve the steering, but then you'd have to move the seat (impossible) and even if you could the centre of gravity etc would all go wonky and the thing would risk tipping over? ;-)

I've seen a front-wheel hub conversion on a C5 from start to finish..the front fork drop-outs are only 85mm so need opening out, but that's not a problem as they're made from strong steel and you can put the braces on to stop the motor spinning out or weakening the dropouts. The conversion I saw was a straightforward rear drive swap for front-wheel drive 24V 250W hub motor. And strangely, the guy who did it said after riding it..he preferred the ORIGINAL C5 motor and rear drive..it handled better and went faster?! And that's off the old 12VDC motor. That must be some well engineered motor and gearing arrangement eh?

 

[Deleted member 4366]

If you go with a front motor, you'll need to spin it very fast. That means a 24v or 36v one at 48v. I just did a Brompton with a 328 rpm 36v Q85 from BMSB. It maxed out at about 15 mph.


They also do this special high speed one that could be just what tge doctor ordered:

https://bmsbattery.com/ebike-kit/178-q8512-200w-250w-12-front-driving-brushless-motor-with-12-rim-ebike-kit.html

 

[soundwave]

http://www.ebay.co.uk/itm/ELECTRIC-CAR-VAN-25-90-KW-PEAK-AC-TRACTION-MOTOR-REDUCTION-GBOX-CONTROLLER-/222072283607?hash=item33b48a21d7:g:yukAAOSwoudW9R-C

http://www.ebay.co.uk/itm/EV-Traction-Motor-Controller-HPEVS-AC50-Curtis-1238-7501-electric-vehicle/191848672523?_trksid=p2047675.c100005.m1851&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=36382&meid=151ebe9fed93451199994f252c8a9a44&pid=100005&rk=3&rkt=3&sd=222099714722
that give it some wooff

 

[morphix]

If you go with a front motor, you'll need to spin it very fast. That means a 24v or 36v one at 48v. I just did a Brompton with a 328 rpm 36v Q85 from BMSB. It maxed out at about 15 mph.


They also do this special high speed one that could be just what tge doctor ordered:

https://bmsbattery.com/ebike-kit/178-q8512-200w-250w-12-front-driving-brushless-motor-with-12-rim-ebike-kit.html

I had the same issue when I converted the Mezzo. Because it has the same size 16" 349mm wheel rims as the Brompton I needed a very high RPM motor. I chose a factory in China that made kits to order, and it worked beautifully, very fast RPM and just the right amount of torque. I did a comparison side by side of 24V and 36V and certainly at 16" with the steep hills all over my town, 36V wins hands down..24V just lacks the umph and speed (even on the flat couldn't hit 15.5mph without pedaling whilst my 36V Mezzo can easily) in 16". I think you're probably right, 48V might be a good idea.

General rule of thumb: The smaller the wheels, and the heavier the vehicle, the more voltage you need?

The C5 is going to need massive amounts of power then. And really weight and space is not a problem like it is on an e-bike. It was intended to be an electric vehicle, so let it be so. It can have 48V Li-ion battery for front-wheel and a car battery for rear motor if need be. I'm just wondering about the arrangement of the batteries though...and also what kind of brakes for 48V? brake motor-cut out would have to be absolutely fail-safe!

If you look at the original motor on the C5, being on the one side, the C5 has a tendency to pull to one-side if you brake suddenly, and even goes onto 2 wheels when you steer sharply at high speed. These are issues will need to be addressed when modernising it.. maybe then having a load more weight on it (60kg is the legal limit anyway for an e-bike?) is not such a bad thing. It's a catch 22 situation though. If you add a lot more weight onto the C5, it would probably cancel out any gain in power and speed? Unless you had really highly efficient motors, excellent gearing and a lot of torque!

Once you take the weight above 45kg+rider you're really crossing over from e-bike to electric vehicle..and electric cars (even micro-cars) nearly always use deep discharge capacity lead acid batteries 48V? I'm not sure Li-ion would take the punishment of the weight and drag of the C5 unless it was 40Ah...that's going to be expensive!?

Maybe a better approach to power might be using the 6V lead acid batteries used on some e-cars? You would need eight of them though to get 48V. There's only so much space on the C5...hmmm maybe you could probably fit 4 either side of the seat (2 each side) that means 4 more would have to either go behind the seat on the chassis near the rear motor area, else you'd have to sacrifice the boot space (it's not that usable as a boot anyway really can't get much in there, I think it's 10 cubic litres).

 

[soundwave]

Tesla is using Panasonic’s lithium-ion batteries for its cars

http://www.bga-reworking.co.uk/e-bike-batteries/panasonic-ncr18650b-3400mah-li-ion-battery-flat-top-unprotected.html

 

[morphix]

http://www.ebay.co.uk/itm/ELECTRIC-CAR-VAN-25-90-KW-PEAK-AC-TRACTION-MOTOR-REDUCTION-GBOX-CONTROLLER-/222072283607?hash=item33b48a21d7:g:yukAAOSwoudW9R-C

http://www.ebay.co.uk/itm/EV-Traction-Motor-Controller-HPEVS-AC50-Curtis-1238-7501-electric-vehicle/191848672523?_trksid=p2047675.c100005.m1851&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=36382&meid=151ebe9fed93451199994f252c8a9a44&pid=100005&rk=3&rkt=3&sd=222099714722
that give it some wooff

Ha it surely would! But the little C5 would probably back-end and just go nose up if you installed one of those in the back lol. I'd need to put on some weight myself to balance it out lol

 

[soundwave]

wheelie bars and a para shoot lol

 

[morphix]

Thinking about the catch 22 with C5, the limited size of it as an EV, and the need for 48V to make it handle hills and speed properly like an EV...you can understand why most of the mod approaches have abandoned electric and moved to gas turbine or petrol. Makes sense.

I absolutely want to keep this road legal (well at least appearing to be) and 100% electric. So going to have to do some creative thinking here and plan this carefully.

It may well be that the original motor (although 31 years old) is the best way to power this thing, after all it was engineered specifically for the C5. It probably just needs TWO of them, one on each side of the axle? Then for batteries it could be 24+24V maybe, and not touch the front wheel.

 

[trex]

the C5 is such a poorly designed trike, the rear axle does not have a differential, the steering is difficult to control. It does not matter whether it can be retrofitted with a front or rear kit, the thought of a fast and strong motor on it fills me with fear.

 

[soundwave]

could you not make a bracket at the rear to use a hub motor like the above bike?

should then be easy to get the axle sprocket in line stop it going side ways.

 

[morphix]

Day 1 - Cleaning the front wheel cover!

When I bought the C5 it was missing it's iconic front-wheel cover. And in the C5 world this is a very bad thing. I asked the 77 year old original owner if he knew where it was. He did not. So to my utter surprise and amazement, when I opened the boot of the C5 upon its arrival, there inside, was one very dirty front-wheel cover!!

Bizarrely in the world of the C5, the front-wheel cover is the most expensive part of the vehicle (to replace!). They so rarely come up for auction that when they do, they usually sell for £80-£100 each.

Yup, just for two pieces of thin plastic and some yellow reflective tape.

Crazy. Supply and demand though. Demand is there, but original parts supply is not. That's why a C5 (even one totally beyond repair) is nearly always worth much more in parts than being sold whole.

So when I was coming back from my storage unit on Friday after putting the C5 into storage, I brought the front-wheel cover back with me, as it looked like it needed a damn good clean!

Look at the difference 30 years of muck and dust removal makes to just one part of the C5!




From this:

To this:

And from this:

To this:

Sinclair even put his name on the inside of the wheel covers! Damn that guy liked to see his name on stuff. Is that the serial number below? Could this be the 85th C5 to roll off the production line??! We shall we find out when I see the paperwork in the boot as well next time.