Cargo Bikes

I’d expect the design is to allow the original bike structure to remain the same and make the cargo an addition rather than full modification? Looks like the mkii design is a style not far from the way xtracycle attaches, so the frame remains structurally sound without risking any longer stays or anything?

If the mallet can hit you you’re too close!

How’s the pashley trike coming along @M_A_X?

The cargo bike taxi episode of dragon’s den is on now.

Here's my DIY cargo, it's was in test ride mode in this photo, I'll post finished pictures when done

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Awesome stuff!

I like the bend in the steerer bar- to make room for the wheel I guess?

Good stuff! Can get a full length front flap with that.
Need to work out a solution for bullitt for a longer front flap, has to be strong enough to not go backwards under the front wheel when reversing but floppy enough to not affect the steering. Ride on a lot of canals and back lanes, underside of it is seriously dirty

Yeah gives front wheel clearance without the steering bars been too far out.
It's now a bit different as bad measuring made the BB and handlebars a bit low,it rides alot better than I thought it would

Love it. Like the exposed steerer with separate support. Suppose its made it easier to maintain the integrity and strength of the main beam.

Great work. The joyous moment of going for your first test spin and it actually working is still fresh in my memory.

In all respect: This thing looks like a total deathtrap to me.

made the BB and handlebars a bit low

I was going to say...BB height is a bit terrifying

The separate support and steerer is a trampoline frame pole, I used whatever I found and was trying to not get involved in cutting the frame as I'm a joiner not a welder, would make it different next time as had a few head scratch moments, total cost will be around £200 so all round happy

Testing was done two fold
First two people jumped up and down on the load area,it flexed alot
Then someone sat in the box while I rode off a kerb
It flexes but I like it, feels like suspension

Front head tube angle is also pretty severe

That's a picture of my attempt for comparison. Taking 100+kg with a smile without me worrying to die any minute. Mild steel profiles are quite cheap, it was under 100€ for tubes and profiles all in.No need to put yourself and others in danger. You also want two functioning brakes on a bike like that.

This thread is giving me a throbber

Head angle looks steep but handles fine unbelievably,Will have brake's and gears when finished also has stoppers on the fork to stop the wheel flopping to far over

Quick pic of revised frame

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@user67706akajimmythegrin great project, but my comments would be the same as @AngusMacGyver. Even with the revised frame (unless it's still work in progress...) the front end needs more support under vertical load otherwise it will flex loads and eventually fail. Look how deep the sections are on Bullitt bikes for example and like AngusMacGyver's repurposed Muddy Fox above. Pedal clearance would be a concern if it's still the same as your photo above...
Keep it coming though... :)

Thanks for all the input so far
Would things improve if I added the orange lines and possibly take the purple line away?
BB is now higher :)

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Would add a bit of colour for sure!

you need some triangulation or gusseting.

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I'm no structural engineer, but the front end is lacking a massive amount of torsional rigidity which means the lone purple tube in your picture will twist under load/change of direction/cornering. Adding a deck will add some structural integrity, but I suspect the orange lines you show if placed at a different plane/height (from viewing the bike side-on) will add torsionally rigidity, whilst creating improved top-load (in the same way the deep rectangular box section on Bullitt bikes do.

Looks like a great project, jealous of what you're up to, but I have a house to renovate so any bike related projects are on hold...

This is more akin to bullit's approach and would not compromise your load platform as much.

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That makes sense,do you think the box will do the same job? It's 18mm ply which I glued and screwed with a flexible glue,it fits snugly in the frame and was going to tap screw it on, it's just held on with the yellow clamp to test

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If you screw it on properly it should be plenty stiff.
Then you just need a little bit of horizontal support behind the box. Like in your own sketch and my second one to avoid sideways flex.