Miles' Project 1 [eMoulton]

[knoxie]

Hi Miles

Wow that was so worth the wait!! has Randy seen it? hmm very nice indeed, how does it perform? what kind of top speed have you seen, I am guessing its a little less than Randys bike due to the wheel size, I bet its pretty quiet as well? love to see some video of it as well.

I was looking at getting a Strida for work! and was looking at ways to add a motor to one, useful that you can get the bits as spares as well! nice job on the clutch as well, did you use a one way bearing and press it inside the gear?

Dont see a problem carrying the batteries in a rucksack, doesnt look like you are after a huge battery capacity? a nice slim pack of A123 in there should give you enough juice.

Thanks for posting the pictures they are superb and I think detail about the cleanest build on an upright bike that I have seen to date, it looks like an off the shelf bike.

I think you could substitute Randys motor for another motor should folks wish to make their own rigs, so maybe a kit of parts might be a good idea, looks like a Kol or a BMC would fit in there nicely.

Thanks again and if you can get some video that would be great.

Knoxie

 

[Miles]

Hi D,

Yes, we must meet up while the weather's still fine. Greenwich seems to be a fairly central point There's a handy hill for testing in Greenwich Park

First, I need to get a decent battery..

 

[Miles]

Hi Knoxie. Thanks!

I geared it with the intention of going with 48 volts when I get a new battery. With the present 36 volt set-up, I'm getting a top speed of about 19mph (off-road so, with a more optimal 48 Volt set-up, about 26mph - which is all I need.

You can draw peaks of over 35 amps from the 4 Ah of Ni Cads but you certainly pay for it (energy wise).

Averaging 12 Wh per mile in a hilly area - should be able to improve on this, once everything is optimised.

The backpack, with batteries in, weighs 6.5 kg - I really don't notice the weight at all when I'm riding.

The good thing about Randy's motor is the form factor - the case is only 60mm deep. You might need a longer BB axle to fit a Koll or BMC in, perhaps?

Adding some power to the Strida sounds like a fun project

Yes, it's a one-way bearing but bonded into the adapter that I made. My first pulley build used the Strida 3 pulley which has a fixing for an 18t sprocket as its center - so it was easiest just to use an 18t freewheel, for that - but I got fed up with the clicking sound...

Miles

 

[knoxie]

Hi Miles

Yes really nice job indeed, speed sounds about right to me as well, dont see any reason to go over 26mph myself these days, any idea what you are going to do for a battery? nice bunch of life cells or maybe a pack of headways? you could build a nice A123 pack.

You will find the jump from 36 to 48V with decent batteries will make a remarkable difference in performance also, I would be up for a meet up some time in the summer, we can drag DC along and also see if we can rumble Richard Papa and his optibike, should make for a good video as well!!

Any chance of some close up shots of the rear wheel and the setup you have used on the strida crank, thats very interesting, belt drive must be a good deal quieter than chain.

Cheers

Knoxie

 

[Miles]

Knoxie,

Still haven't decided which batteries to go with. I was quite tempted by the BMI 12Ah LiFePo4 cells but I'm not sure if they're available again, yet.

Yes, we must definitely all meet up. I'm dying to have a go on the Optibike.....

Ok, I'll take a few close-ups. The belt drive is pretty quiet, as is the motor - noise is something I care about. You could approach someone from behind in a park and they wouldn't hear it. Might be a tad louder on 48 Volts, perhaps?

Anyway, I'm convinced that belt drives are the way to go...

 

[recumpence]

Matt

 

[Miles]

I'll take that as a compliment

Thanks Matt.

 

[knoxie]

HI Miles

Yes looking forward to the photos, Randy was always reluctant to show anything other than really blurry shots of his rig, the Belt drive is certainly the way to go I reckon, chain would also be fine but the belt must be a lot quieter, it will be interesting to see if it stretches at all? I bet its quiet too, is that the speed controller underneath the bottom bracket then? looks like you are using a Magura throttle as well? only the best!! I have been using one for 4 years and wouldn't use any other make on any of my rides! apart from the BMX!as he never gets wet..water and hall effect throttles often = bad news.

I think this may spawn quite a few copies though as I don't think you could have done it any better!! the fact is you could use a much less powerful motor with this set-up and still get good results, its good enough to even approach the makers of the bike? it could be made UK road legal with a nice light battery pack with an off road switch to up the power.

Sometimes the best things in life are worth waiting for!! now I know why you hung on before posting!! some very envious folks on here I would bet!!

Knoxie

 

[deecanio]

Hi All,

definately agreed on the belt drive, nice and quiet and looks just right i think for an ebike drive, i cant put my finger on exactly why. but when i think chain driven i think gas, but with belt drive i think e weird.
Things generally just got a LOT more interesting for me personally with miles/matts/scotts bikes, im already hoping to get a rc motor and belt drive on my bike when we know the best/trusted route.I really think a new breed of ebike is born, and more importantly it's doable to the home builder with small controllers, much smaller motors things are looking good
Agree with paul on the finish, like factory built
if anyone decides a firm day i'll be there it would be way cool to meet up and get to see all the bikes and meet you guys

*edit* great if anyone could get richard along so i can slobber on optis lines that would be sawesome (not typo), how about steve head too ? lol, i think of steve as the paul weller of ebikes - he's had cool bikes for years
cheers,

D (envious +1)

 

[Miles]

Knoxie, you're too kind....

I don't think these belts stretch very much at all - we'll see.

Yes, Magura throttles are great. Did you see that the new AstroFlight brushed controllers come with them as well?

Yes, I'm planning to get in touch with Moulton - not that they need any design help from me.... just to encourage them in this direction, again. After I'd started this project (inspired by Randy's build) I discovered this old patent , taken out by Alex Moulton in 1966... so, it seemed like I had his approval to do this

 

[Miles]

how about steve head too ? lol, i think of steve as the paul weller of ebikes - he's had cool bikes for years

:lol: :lol: :lol:

 

[Miles]

D,

Yes, exciting times. This forum will get a lot busier, too....

Maybe we could have a UK seminar on ebike design.... like the velomobile one?

 

[jerryt]

I Just wanted to join the chorus of folks who admire your craftsmanship; excellent choice of components, professional and top notch. Thanks for sharing.

 

[knoxie]

Hi Miles

That old patent was spot on! apart from the gas engine bit, but at the time we didn't have the batteries or motors sorted! some say we still haven't :lol: I still think they will love it if you approach them with it, it really shows off their bikes well too, I had never heard of them before? interesting design, a really nice looking ride.

I don't think that Steve Head does much these days e-bike related, I think he still uses his bikes but hasn't developed them any more and doesn't read the forums much either, his little bikes have inspired so many builds now I have lost count.

I will be interested to hear what our old friend Randy thinks about it, bet he is pretty chuffed someone finally did it and made it a whole lot better looking to boot.

If you can get some video that would be great and yes I would be well up for a UK e-bike meet of some sort, need to meet Jozzer and Nick as well, I am sure we can all something out? need to set a date and stick to it I suppose!

More pics and video if you can!! thanks again what a superb machine

Knoxie

 

[Miles]

Knoxie,

Here's the Moulton website: http://www.alexmoulton.co.uk/

You might also be interested in this video: http://video.google.com/videoplay?docid=-8522870086389552343

 

[scottclarke]

Well Miles, you have inspired me to carry on with my build! Seriously, mine looks just awful with wires and whatnot hanging around!

I'll be losing the fake water bottle, get the esc properly hidden under the seat, etc etc......... Won't be as nice as your for sure - but - I can try!

 

[Miles]

Here are a couple of close-ups of the rear wheel. There's not much to be gained from taking the wheel off unless I also remove the derailleur sprockets, which I'm reluctant to do at the moment because they are carefully shimmed to be concentric and it's a bit of a fiddle. I'll take some more pics of the one-way bearing assembly etc, next time I take it all apart. As you can see, the pulley needs to be as close to the spokes as possible, without actually touching, in order for the belt to clear the frame.

 

[knoxie]

Thanks for that Miles!! that looks so slick

Knoxie

 

[Miles]

Well Miles, you have inspired me to carry on with my build! Seriously, mine looks just awful with wires and whatnot hanging around!

I'll be losing the fake water bottle, get the esc properly hidden under the seat, etc etc.........

Looking forward to the photos of the spruced-up version, Scott

 

[recumpence]

Tell me about your clutch, Miles. You mentioned making it yourself. Is it a slipper clutch?

Also, is there a oneway for free pedalling?

Very nice work. VERY nice, indeed!

Matt

 

[Dee Jay]

Big Up to Miles!

Good to see that there are people on ES who care about elegance and class. 8)

J

 

[Miles]

Hi Matt,

It's just a standard one-way clutch bearing, used as a freewheel substitute. I only made the housing/adapter for it - I'm not as prolific as you

The cranks are freewheeling, using a White Industries ENO 22t freewheel on trials cranks. I had a chainring made especially for it but others have made adapters to standard chainrings. The 22t ENO has handy circumferentially milled weight saving slots that one can use for fixing.... not that it's a problem to drill the fixing holes, with a suitable drill.

So, the one-way bearing isolates the motor drive so that you can pedal as a normal bike, without any extra drag, and the freewheeling cranks decouple the pedals when you use the motor without pedalling. For normal freewheeling, the original freewheel in the hub gear kicks in, of course.

 

[Miles]

Thanks J!

What we need is a bit more consistency of style...

There are 2 excellent books, for those that care about these things: "The Nature & Aesthetics of Design" and "The Nature & Art of Workmanship", by the artist/industrial designer David Pye.

 

[recumpence]

Miles,

You have class. Man, I love the superb simplicity and elegence of this design.

Oops, I need to clean the drool off my keyboard! No, wait, that is not drool, it is a tear.

You moved me, Man. :wink:

Matt

 

[Malcolm]

"The Nature & Aesthetics of Design" and "The Nature & Art of Workmanship", by the artist/industrial designer David Pye.

On my holiday reading list!
Cheers
Malcolm