Bafang Motor Trailer Project Completed.

cirrus18

Pedelecer
Apr 22, 2009
67
0
Cornwall. UK
Sorry, but trailer is now SOLDI am selling this trailer and I have an advertisement running in the Classified section.
Please look here:

http://www.pedelecs.co.uk/forum/classifieds/7464-bafang-8fun-motor-power-pod-trailer-sale.html#post93847




If you're not interested in a trailer this could make an inexpensive way of converting a 16 inch wheel size bike, such as a Brompton, to electric for about the price of a new battery. The motor is mounted in and designed for a 16 inch wheel. Top speed about 18 mph.

The battery alone with shipping, cost me US$470 about £300. So you see, you get everything you need for the conversion and anything you don't need you could sell on.
If you are interested and would like more information, please phone Paul on phone number: 01637-875356



I have modified my Specialized Sirrus with new lighter components (carbon forks etc) and it now weighs under 20 lbs.
On this bike I have done many long tours towing a Bob trailer, longest being, crossing the USA from Washington, DC to San Francisco.
I didn't want to modify my bike by adding a motor, but needed help getting up hills as age has caught up with me. My aim is to pedal without much assistance most of the time.Das Elektrorad von Frank Scheftlein: Komplette Pedelec- / Elektrofahrrad Umbausätze und Ersatzteile von Bafang, Puma (eZee), Tongxin u.a.
Being so very familiar with the Bob trailer, knowing how well it works and how easy it is to tow, it seemed to me to be an obvious choice to build a motorised mono wheel trailer using some of the Bob components.

I designed the trailer to be just a ''Powerpod'' as I have no need for it to carry luggage.

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I bought the Bafang Motor and controller etc from Frank at and found him to be very helpful.

For the aluminium I raided a local stockists off-cuts bin and obtained what I wanted for a few pounds.
The towing forks for the trailer and special quick release I got from the Bob agents, Amber marketing Ltd. Rather expensive at £65 for both. But at least I knew that I had a very professional, safe towing system. The forks come complete with the swivel which has Teflon bearings and uses just one long bolt to attach it to the trailer. So you don't have to make anything complicated here.

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Building the trailer was relatively easy. I used stainless steel rivets for strength and used a electric jigsaw to cut the aluminium tubing.
The controller and the PING 15 amp hour battery were installed in plastic food storage containers and everything covered in a waterproof yellow cover.
I did experience a little bit of wheelspin going up hills, so I put all the bits and pieces which I normally carry in my saddlebag into a bag on the trailer. The extra weight helps but it's not perfect. Judicious use of the throttle is still required.

I didn't like the pedelec system and holding onto the throttle was a pain. I removed the return spring from the throttle and as there wasn't sufficient room on the handlebars I mounted the throttle on the centre stem, devising a friction pad so that the throttle doesn't move and stays set.
From Maplin's I purchased a miniature switch and a waterproof cover, put these on the handlebars within easy reach of my left hand. This switch switches on and off the centre wire which goes to the controller. I can now leave the throttle set and just switch the motor on and off as required.
Also got the motor safety cutout switch which comes integral with the break leavers.

The 11 position switch/cruise I just use as a battery indicator.

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Don't know exactly how this battery indicator works, the right-hand/last red LED is on after charging the battery fully and presume that as the battery level goes down the other LEDs light up accordingly. Anybody know?
The other day I went 30 miles and the battery was still indicating fully charged so I thought the next day, without charging up the battery, I would keep going until the battery went so low as to cut off. After another 20 miles, now a total of 50 miles, it will still indicating fully charged, the battery level hadn't switched off, so there was still juice left.
I had other things to do so couldn't continue any further.
I am amazed to be up to go 50+ miles on one charge and averaging 12 mph in the process. When I have more time, I'll do another test to see how far I can go and this time I will keep going until the motor does cut out.

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The first controller I got from Frank had a problem in as far as that just about every time I opened the throttle, or when I was using the pedelec system and started pedalling to resume power, the motor would switch itself off. Very annoying. Has anybody had the same problem with these controllers I wonder?
Frank changed it for a new one, this one seems to be an updated version and it doesn't have this problem but something else.
On my old controller the top speed was 17+ miles an hour, very nice, on this new one, the top speed is under 12 mph, most annoying.
This is where I need some help from you guys, has anyone had hands-on experience in reprogramming these controllers? I need to be able to keep everything exactly as it is but just increase the top speed setting, if that is possible.
I've got the programme and special USB lead from Frank to be able to do this but I am just a little bit worried as I've never done anything like it before. I don't want to muck something up.

Yfrog - dscf0492small - Uploaded by cirrus18

I am pleased with how my project turned out. It's doing exactly what I wanted to do in giving the assistance I require climbing hills. So I'm now getting all the fun of cycling, keeping fit and enjoying the fresh air without the pain.
I will keep this set up for the time being and perhaps next year, when things move on a bit, change it for a smart new electric bike.

Why no pictures, just links, anybody know?
 

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jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Nice job.



To show the pics in the post copy the link after you veiw the picture then go and edit the post. Click on the "mountain icon" up there ^ in the edit window and then paste the link into the window that pops up. Click ok then save and they should display.

Regards

Jerry
 
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cirrus18

Pedelecer
Apr 22, 2009
67
0
Cornwall. UK
Nice job.



To show the pics in the post copy the link after you veiw the picture then go and edit the post. Click on the "mountain icon" up there ^ in the edit window and then paste the link into the window that pops up. Click ok then save and they should display.

Regards

Jerry
Thanks, but that is exactly what I have done. I've tried it again and it still doesn't paste the picture just the link. I am using Firefox perhaps it only works with Internet Explorer do you know?
 

jerrysimon

Esteemed Pedelecer
Aug 27, 2009
3,292
112
Cambridge, UK
Click on the picture first so just the picture shows not the yfrog web page. Then copy the link and post as explained.

If you can't I will do them for you.

Regards

Jerry
 

flecc

Member
Oct 25, 2006
52,851
30,402
Nice job Cirrus. Most powered trailers rely on battery weight to maintain traction, so many have used substantial SLAs or even car type lead acid batteries for that.

I use Firefox. Your pics problem is the file type, *.jpeg, the limit for those being 19.5 kB and your pics are larger. They are the same technically, but this site host differentiates them for some reason, possibly for MAC compatibility.

If you have software to convert them to *.jpg, the limit become 97.7 kB and your pics will then be displayed. I've converted this one for you:

Clipboard01.jpg
 
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Tiberius

Esteemed Pedelecer
Nov 9, 2007
919
1
Somerset
Nice work, Cirrus.

I wonder if there is a way of getting the battery weight right onto the trailer wheel, maybe by having two batteries mounted either side of the axle. That would help a bit with the traction.

Another thought, and flecc may be able to help here. What is the legal position with a trailer? Is it a bike or a trike? An e-trike is allowed to be up to 60 kg instead of 40 kg. That would allow for some serious range or cargo capacity.

Nick
 

flecc

Member
Oct 25, 2006
52,851
30,402
I don't know of any specific regulations for powered trailers, but production ones are known in Europe so there must be some regulations permitting them in the EU. The EU also has regulations for child trailers and some while ago I've seen mention of a UK maximum width for cycle trailers but cannot locate anything on the law relating to that.

I don't know whether it could be considered a trike, but one can use the argument that as essential parts of the powered trailer system are on the bike, it is one indivisible powered vehicle, i.e. a tricycle.
.
 

eddieo

Banned
Jul 7, 2008
5,070
6

daniel.weck

Esteemed Pedelecer
Aug 8, 2009
1,224
1

NRG

Esteemed Pedelecer
Oct 6, 2009
2,592
10
Dan beat me to it....I also seem to recall on ES that some of these controllers have an internal jumper setting for setting the speed...may be worth having a look.
 

cirrus18

Pedelecer
Apr 22, 2009
67
0
Cornwall. UK
I am selling this trailer

Sorry, but trailer is now SOLDI am selling this trailer and I have an advertisement running in the Classified section.
Please look here:

http://www.pedelecs.co.uk/forum/classifieds/7464-bafang-8fun-motor-power-pod-trailer-sale.html?highlight=cirrus18


If you're not interested in a trailer this could make an inexpensive way of converting a 16 inch wheel size bike, such as a Brompton, to electric for about the price of a new battery. The motor is mounted in and designed for a 16 inch wheel. Top speed about 18 mph.

The battery alone with shipping, cost me US$470 about £300. So you see, you get everything you need for the conversion and anything you don't need you could sell on.
If you are interested and would like more information, please phone Paul on phone number: 01637-875356
 
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