CliffordK

I recently picked up a used homebuilt cargo bike for $40. Needs a bit of work.

Hopefully the restoration will go quickly. I'll try to post notes of the restoration / rebuild as it goes on.





Unfortunately it had a broken weld on the frame. The two tubes had two plates welded between them which had also broken loose. Somehow the canti brakes also disappeared between when the photos were taken and the sale. No rear wheel, but a standard 26" should be fine.

And the paint job is much worse than it looks in the photos. I probably should strip and repaint.



Looking at the bike, some things are good. Some aren't so good. Some things make me wonder what the builder was thinking.

Personally I think the double tube design must have had a lot of both vertical and torsional flex. The plywood might give it some strength, but it wasn't really designed for that either.

Hopefully tomorrow I'll touch up the broken welds. Then perhaps I'll put it back together and try it out, but I expect to be building a little more extensive front support system.

long john

Cool job. I built a double tube like yours it flexed a lot. It's waiting for rework. Good luck.

CliffordK

Here are my rough plans.

Looking at that bike, I think the cargo part was cheaply made, so perhaps it would be best to scrap it and start over. But on the other hand, it is a good base with some good ideas.

I'm just suspicious that one is going from essentially an open truss on a standard frame to two parallel tubes on what should be a much heavier duty cargo bike. It obviously failed, so either it had too much flex, or poor materials and assembly. Or both.

Anyway, my plan is to scab a strip of chromoly between the two tubes to essentially make it one solid oval tube. This should give it significant rigidity.

Then I'll frame in the cargo area with bi-level tubing with cross-bracing.

And, of course, design a kick stand. I should end up with a bike that should be able to handle 200 or 300 pounds of cargo, perhaps more, but I seem to start failing at about 500 lbs cargo.

I'm using a straight-pull trailer, so a solid rear rack will also be helpful.



I may still choose to reassemble and test it as-is, just to get a feel for it.

lopek77

I'm little jealous...I always wanted to have one, but never saw it anywhere other than on YouTube or TV lol
Please keep us posted. I love to see the progress and the finished bike. Good luck!

squirtdad

it would be heavier but you might consider rectangle box tubing instead of plate.

CliffordK

I do have a little of the rectangle tubing left which I had used on the longtail rack. But it is just mild steel, I think. Still strong since it is about 1/16" thick.

However, I think I will gain lateral strength by building the frame out laterally, so just tying the tubes together should be sufficient. They had a single section tied together in the middle originally, but I might even get a similar strength with several short chunks with gaps in between.

I met a guy today who did a specatcular job on a homebuilt longnose. I think with a single 2" tube for the front. He was test-riding, but also still building on it.

ksisler

Clifford - having now looked at the pictures, I would supply the old adage; If it looks like crap, it probably is! I really don't see anything worth spending on time and money on to repair/restore. Best use is probably to use it as a concept to design a new build upon. But then again front loaders are iffy in terms of ride-ability and turning. Could just eat the $40 and google for pictures of modern cargo bike with the load behind the driver. Clone one of those? Or one could just buy one of the available ones such as the LHT brand which are much beloved. Amazon has a nice un-cheep front loader here to buy or clone;

Amazon.com : Virtue Gondoliere in Atlantis Green, Cargo Utility Bicycle, 7 Speed Wagon Bike : Sports & Outdoors

Hope that helps

/K

CliffordK

I haven't made a lot of progress on that bike lately. I've done a fair amount of stripping, and cleaned up a few of the welds. I will say that it is a pain to weld between two parallel tubes, and perhaps that contributed to the break.

I am planning on using it as a prototype and practice frame. See what works and see what doesn't.

I saw that Virtue bike on E-Bay a while ago. I was surprised that it is rated at 66 lbs. That is hardly more than I put on the rack of my road bike. Ok, so I sometimes buy in bulk. I've had over 100 pounds on the rack of my longtail (much more on the trailer), and didn't like the heavily loaded rack. The bike was ok, but it just seemed unwieldy. Hopefully the longnose will be easier to load and manage with heavier loads with the lower center of balance.

I have looked at some of the bikes they make at CAT locally, and did meet a guy locally that had welded up his own cargo bike for use as a mobile bike mechanic shop. Of what I saw, it looked like a nice job.

Here was the handlebar stem on the green bike above. Apparently the builder welded a piece of conduit in the middle, with a pretty poor welding job. I have to assume the leverage isn't too bad, so it doesn't take much. However, if I ever start making more frames, the steer tube will be cut long on the lathe (I hope).



At the moment, I'm keeping with mostly straight pipes, but am keeping the mandrel bender in the back of my mind.

ka0use

you have skills I don't, and I see no harm in practicing those skills. if the project turns out great, then that's good.
if it doesn't, you've still learned something.
keep pushing.

CliffordK

I've repaired some welds. But, was going to order some steel, and didn't get it finished yet. Thanks for reminding me.