Wednesday, 6 November 2013

DIY Longtail Cargo Bike - Chapter 4

DIY Cargo Bike - Chapter 4 - Intro

Having built the frame and installing a minimum number of componenets for the maiden voyage there were a few niggly bits to sort out;

  1. Gears
  2. Lighting
  3. Test for Strength

Did you miss Chapter 1, Chapter 2, or Chapter 3?

DIY Cargo Bike - Chapter 4 - Gears

I only ever intened to have a 1 x 9 setup on this longtail cargo bike, as I don't like front mechs. So I ordered quiet a small chainset, a 34 tooth M-ighty chainset from SJS cycles.

34 teeth and a tight chain, just about OK

This would have been fine if the chain tension was very high, as with a single speed or hub gear bike. But the "flop" of the chain using my deriallier gear system caused immediate problems with the chain rubbing on the foot plates of the bike in all but the lowest gear (larger rear spocket gives more clerance).

So I tried to add in a chain "support which was a jockey wheel from a rear mech, and some peices of metal welded to the frame, to lift the chain up over the rear foot deck, this was a very noisy soluitoins with tons of rub in all but 5th (central) gear.

So in the end the soluiton was to get a larger chain wheel up front, not idela on a bike designed to ccarry heavey stuff, but I do value peace a quiet.

On ebay I found a single speed chainset with a 44 tooth chain wheel, so I bought that.

This works OK. I also had to trim back the inside edge of the foot rest to allow a little more clerance for the chain.

DIY Longtail Cargo Bike - Chapter 4 - Lighting

I am a fan of hub dynamos and the front wheel I had spare has a  got one, a Shimano DH-3N20 which is a good bit of kit, for lights I pinched the Busch and Muller Lumotec Lyt Senso Plus from my main bike, and purchased a Axa / Basta Ray Steady LED nothing to say other than a thank youto busch and muller for the extra long cables thery oprovide with there lights which reached from the front wheel all the way to the back.

DIY Longtail Cargo Bike - Chapter 4 - Test for Strength

There is quite a bit of flex in the bike, from side to side that is. But the loads will be applied downwards so I wasn't too worried abot that. I way 80 - 85 kg so I knew the bike was good for that.

Next load up was me plus a 20 kg parcel, which was strapped on to the foot plate at the rear , so that was 100kg.

Next load up was me and my two daughters (leap of faith I know) so that would be 110 - 115 kg. As you can see they are both very happy, as am I.

So happy days. All done. Expect some stupid pictures of me taking fridges to the dump in a few weeks. . . .

Update: 10/02/2014

After a few months of riding I have a small update. All there is to say is that the bike is doing well. We have had various family excursions on the bike, and I have taken numerous large parcels to the post office using it. The only modification since this post has been to reduce the size of the chain ring from 44 (yes I know) to 38 teeth. A lot easier on the knees.

Some pictures below of a large load.

Went about 3 miles with this load. An antique(ish) foot locker type thing.

Flood Risk

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  1. Great job and quite inspiring. Thanks for all the details.
    Been toying around with a similar project.

    keep posting!

    1. Let me know how it goes. Thanks for the comment. Post a link by all means.

  2. wow that's is awesome! I admire your skill and work! I would love to learn and try to make my cargo/children loading bike one day. For now, I am satisfied with just my green vintage with attached child bike seat.

  3. Thanks flowershin, this cargo bike has a very limited life span in terms of usefulness, the kids are already pretty heavy, and the gearing is getting lower and lower all of the time. I think pretty soon the oldest will want to ride their own bike or at least a tag along, so for it main use as a child transporter it will only have been used for around 2 years. That being said it has been excellent fun during that time! Happy cycling.