Brompton electrification

[cwah]

Hello there,

I'm posting the news about my brompton build here.

First of all, thanks for all that helped me (Special thanks to John for his help and all the other Catsnapper, Dave, etc).

Here is my motor laced in a sun ct-18 rim:

I'm really really happy to finally see the wheel fitted on the rear fork.

I think I have to start making both forkend parallel. Maybe use some plier or wrench.

 

[Scottyf]

Great stuff Cwah and those involved in getting this far.
I was going to text you yesterday to see how you was getting on.

Glad it's coming along and your now much closer to completing your build.
Just a few more pushes and you'll be cycling around and folding up the bike no problems.

 

[paulhipwood]

Dear Cwah

You have laced your rim radially by the look of it.
Whose motor and spokes did you use?
I want an 80 mm motor for my Moulton - one day

regards
paul

 

[jerrysimon]

Like this

What Moulton do you have ? I have also fitted a motor to a 1970s Raleigh Moulton MK3

Nice job Cwah. Sorry to hijack your thread. Good to see your build coming along.

Regards

Jerry

 

[paulhipwood]

Dear Cwah

It will be good to see your bike built up.
Please post a photo when you can.
Just in case you want to know what Moulton I have its a 20" APB, that is pretty shabby. lol.

regards
apul

 

[cwah]

Yeah, that was a loaaaad of work and hassle. It's almost there.

I'm sooo excited.

Paul, the motor is a mini motor from Conhismotor:
http://www.conhismotor.com/ProductShow.asp?id=76

The wheel has been laced by Catsnapper. He can do it for you for a fee. I prefered to ask for someone as I've never done that before.

I think he cutted the spokes and put double washers on the spokes holes because it was too large.

Don't yet know what this little motor worth, will know very shortly

 

[Scottyf]

I think it will work well to be honest. The direct drive has the ability to be high rpm and the wheel size will be naturally torqey with a modest amount of current. I think it will be a good match.

It will be robust anyway.

 

[paulhipwood]

Ahhhh its for a rear wheel.
Will look on the site fr something for me.
So you will be single (mechanical) speed.
I was thinking of a front hub set up - its hilly around here.
I was ging to buy a motor and lace it myself; but do not know what is the safest lacing pattern to use on a 20" wheel.
The Moulton has some suspension links - this means you have to have clearance around the hub. Most front hub motors are 100 mm between the drop outs. The links would foul the hub. Hence a 80 mm motor is required.

regards
paul

 

[Scottyf]

Tongxin or cute motors seem to be popular with the smaller wheeled folders and tend to be a very good match.

 

[cwah]

Paul, just had the expert answer from Catsnapper about the spokes:
"The spokes I was waiting for were out of stock everywhere, the supplier in fact supplied the wrong ones in the end. TBH, they would have made very little difference to the wheel as the spoke holes are too large for any normal bike spoke.
The double washer setup was a small brass washer that was a close fit on the spoke to help fill the hole, then a nickel plated brass washer to seat the head of the spoke.

The spokes are custom cut DT Swiss 14g(2.0mm) stainless steel. They are laced radially as any other lacing pattern would have created too large an angle at the rim, bending the spoke and creating very uneven pressure from the nipple onto the rim.
With such a large hub and small rim the conventions about the best way to lace a rim are less valid. With a large wheel, radial lacing of a motor would be unacceptable, with a small wheel it's much less of a problem. Quite often as in this case, it's the only practical way to do it.
"

 

[jerrysimon]

Dear Cwah
Just in case you want to know what Moulton I have its a 20" APB, that is pretty shabby. lol.

Moulton's make great conversions with front and rear suspension.

With lots of advice from Alan (Catsnapper) I have also recently built two radial wheels myself including this one for my latest minimalist Moulton build. I will start another thread.

I have been taking lessons

Regards

Jerry

 

[paulhipwood]

Thanks Cwah and Jerry.
It looks as if radial is the way to go.

Don't you have dusty roads in your area Jerry?
My tyres are only that clean when they leave the shop!!!!

regards
paul

 

[cwah]

By the way, my chain doesn't seem to work very wheel on the bike:

It look like their is a node I can't unlace. Am I missing something?

 

[paulhipwood]

Dear Cwah

This is just down to chain newness, after a few hundred miles it will all line up.

paul

 

[Scottyf]

Makes perfect sense. Alot of people do exactly the same on endless sphere with small wheel builds.
Some actual large direct drive motors actuall just fit the rim in a solid layout like the folder motor company.

There good spokes, even with my cack hand build they held up to a load of punishment and 2500w going though them with no issues.
I'd happily buy another set when the time comes.

 

[cwah]

Dear Cwah

This is just down to chain newness, after a few hundred miles it will all line up.

paul

No, it's not that. It can be fitted to the chainset because of the node I can't unlace. Can't even pedal with the actual chain.

Not sure if I have to change the chain or something to remove the node.

 

[paulhipwood]

Cwah

Sorry I was joking - what do you mean by NODE?
I have looked at your picture and it is not clear what is the problem.

paul

 

[jerrysimon]

cwah where is the Brompton chain tensioner ?

You need it to take up the slack and stop the chain falling off when you fold it.

Also you are going to have to check your chain line.

Regards

Jerry

 

[cwah]

yes, this is the problem:

So to solve the problem I have to add the chain tensioner back? Not sure if the chain is long enough now lol

 

[jerrysimon]

Don't you have dusty roads in your area Jerry?
My tyres are only that clean when they leave the shop!!!!

My Moulton gets a lot of attention to keep it looking nice. The Brompton is my work horse, though I even try to wash it down every few weeks. For me half the fun of bikes/ebikes it the constant fettling

Regards

Jerry