Cargo Bikes

Ah that would have been perfect but yes, sadly disk brake needed…

Anyone want a free side stand? Pay postage

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I'll take this, will pm

Il have it pls

I’ll give my usual ‘have you checked recumbent dealers?’ advice.

Ah good shout, not sure if there’s any round here (not London based), but I’m sure there’s a niche bike shop somewhere nearby!

Being in the middle of nowhere hasn’t stopped me from ordering whatever I need (want). It all started with paper catalogues…

Maybe look for it as a folding bike wheel? I found one this way

Cheers, I really appreciate this and @boisb 's story too. It's shifted my thinking a bit which is what I needed - there's too much that could just go very differently from how I imagine.... First kid as well so maybe I should play around with what we have first. Thanks!

Is there data anywhere on what sort of % gradients i should be able to tackle with what sort of loads.

I used a Bosch cx to lug a 30kg trailer up perhaps 20% at the weeknd and I felt it perhaps struggled. But maybe it was due to gearing on the bike. 40x40 smallest I think.

I have a weird use case of my house being up a steep hill and no car access. But I need to lug lots of stuff up, building materials. I think the first option is to get a bigerg trailer and see what the Bosch cx can carry. I was using a burley flatbed, which is too small. Or ok size if weight for towing will be cira 40kg.

I post this here rather than trailer thread as I think the response will be better.

@Emyr I saw your bike and trailer, maybe you have experience?

I used to work for Pedal me, the bikes have a mixture of Bosch Gen2 CX and Gen4 Cargo. Although I think at this point they were all Gen2 CX..

During lockdown they were doing a lot of deliveries for food banks.

When fully loaded there were some hills that were literally impossible to get up, you had to go around. I'd say we effectively hit the limit of what the motor would assist. We couldn't gear any easier as it would risk breaking the rohloff hubs (and voiding warranty). Shame I can't tell you which hills... but with this sort of weight they wouldn't have to be very steep.

The bike unloaded is 60kg, the (stupidly heavy!) trailer was about 100kg, rider could be around 80kg and the food boxes were 5-15kg each. Hopefully this gives you a rough idea of where the limits start to appear.

Thanks for that, helpful. Yes, so I am using a carbon gravel bike. So 24kg, me at 75kg, tailer ~10kg. Perhaps on 15% I will be on a limit around 50kg. I do think I need to gear down a bit. The issue is the hill is curved, so you can't get a great run up and keep pace, you have to slow and navigate.

We will find out. I need to carry a 70kg washing machine next week, so that will be a good test.

dread to think how much this costs. but...
https://www.carlacargo.de/products/ecarla/

In my mind a 70kg washing machine will be no issue for the motor, but it does depend on the gear range whether you'll be able to use it to it's potential.

about 4k for the non e-assist version.

Thanks. I do have a larger cassette so I will fit that if needed.
I think the other issue is the ebike is my wife's and she's short and I'm tall, so me trying to pedal it isn't very efficient. I will try raise the saddle.

Just ordered a new rear wheel for the babboe, but worried I’ve over specced the rim, 36h halo h2 on a halo spin doctor hub with sapim race spokes…?

Now in possession of an xtr di2 group set for it (which is overkill but was a good price) the only challenge I see is that the gear display is for oversize bars, but sure I can find something to shim it with…

Would it be an option to buy a second hand electric cargo bike, use it for as long as you need and then sell it on for hopefully not a lot less than you bought it for?

I don't think it would do more than the Bosch cx performance we have now, pulling power wise? I just need a bigger trailer is my issue. And a smaller gear.

But yes I could buy one, but I'm sure id just keep it long term as it's be great. But I'd like to try use what I've got, as it should be enough.

Sounds like good training. Can't you just HTFU and pedal harder?

It's my Douze 5th birthday this month!

Took it on a delivery with the equivalent of 12 cases of Champagne! That's about 130kg worth.

Still works well, I am on my second battery and get about 25 miles of assistance (full power) in the summer and 12 in the winter

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Yeah sure, it's just the tight corner that makes it hard as you have to go slowly to navigate around. I was more just trying to get a grip on reasonable towing rates for motors.

We tend to avoid anything around 10% if loaded up (70+kg) in Bristol, using Urban Arrows with Cargo line motors. I wouldn't even look at 20%.

There are e-bike power calculators around on the internet that might give you an idea of what is possible.

Thanks.

I thought this was an interesting question, and Jon's real-world answer was interesting too, and fitted in with what I'd always thought, which is that e-bkes are not good at steep climbing - although mid-drive motors are certainly better than hubs.

I had a quick look at the physics to see how possible it looked. The inputs are from above + my guesses, especially the efficiency % at the end - I don't know what the losses would be from motor heat, tyres, from changes in speed / accelerations, air resistance, etc, etc - but they would add up.

This is what I got.

The peak power of the Bosch CX is 850W. @skinny can put in a few hundred watts so the motor doesn't have to do it all. Maybe not impossible, but feels like it is on the edge. If it goes to 20% on a section the power increases proportionately so, on my assumed numbers, the total power goes to 1.33kW, so the rider's share goes up to nearly 500W. Pushing out 500W while trying to handle the bike, steer and have something in reserve just in case...

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