Local shopping by bike with half a cat carrier-basket

This is a 'how to fasten an alternative bicycle basket onto the back of a bike' instructable. It's for when zip ties wont do.

There are other options. Velcro ... if you want to take the chance it wont come away.
Strong magnets ... if you don't mind how they might affect electronic equipment, credit/bank/ identity cards and so on.

I got a cat carrier-basket and mounted the base on to the back of the bike. I could just as easily have used an old tool box, or even an in/out office tray.

I hadn't taken instructable photos of the original on a lady's bike, which has the blue base of the cat basket. (So these mostly just show the cream coloured up-turned top of the cat carrier.)
If your bike has a cross bar, you will notice that when you have a high load, you can't really throw your leg over, so you'll have to do a high step-over the bar.


In our case, we've got large woven bags as shown on the photos.

On arrival at the shop, just grab the bag, shop, fill bag and on return to bike, replace on cat-basket and leave.

Check how much weight your rack can cope with. The one on these photos carries up to just 25 kgs, (55 pounds) so not a weekly shopping for an entire family.

Ordinarily, no need to tie it down either. The blue base shown is 3 years old and no load has ever had to be tied down despite the wind or Belgium's cobbled roads!

But you'll still have to see other people having to unload their bags to place their items one at the time into their bike panniers/side bags.

Step 1 Get a cheap cat basket... or something similar

You'll need;

Urm.. obviously...a bike with a rear rack / carrier

**Materials**

Half a cat carrier-basket, prefably the base (bottom bit) which will be uniformly flat.
Cat carriers / baskets are also sometimes called cat crates, or cat kennels, or catboxes. They are used to transport cats and other small animals without them escaping. I do not mean the cushioned sleeping baskets.

4 biggish round-headed bolts (& matching nuts),
8 wide washers,
4 off-cuts from a roll of perforated metal
4 Spring washers,
2 small narrow bolts, + washers to fit,
2 small spring washers
2 wing nuts.

**Tools**

A Drill with a small drill bit and a larger one.

A biro / pencil/ marker of some kind to pin point where to drill the holes.

I used a vice-grips to snag the metal strips to make it easy to break off.

A round headed spanner (size 13 in this instance) the open ended spanner will do, but a bit fiddly due to limitation of space.

• avoid nuts, bolts and washers made of iron as these may rust, which would be bad for the bike.

Because of the design of the rear rack, on this bike, I've had to cut out a bit of the cat basket to allow a raised bit of rack to poke through. So much for maintaining structural integrity (-:
It's on a bike rack, so it'll not be going anywhere, I guess.

First I unrolled a strip of the metal strip and cut it to around about the length of the bike's rear rack.. Using a vice grip to snag the metal strip and then bend up and down to breaking point..

When I had 4 equal lengths (with holes in line) I paired them off and using a small bolt, washer, spring washer and wing nut, joined each pair at one end.
I just tightened up the wing nuts by hand.

I then slipped these pairs on to the rack so that one strip per pair was above the rack and the other beneath.

Comments

[thewetturd]

I did something similar to add a milk crate to the back of my bike and I have an important warning. I had about 4 pounds worth of stuff in the crate and that was enough to throw off the equilibrium off the bike. I fell twice, the last one, injuring my knee and almost getting run over in the process. I have been riding for about 30 years and am an avid mountain biker. I think that it is safer to either wear a small back pack or saddle bags where the weight is further down in the center of gravity. Be very careful. Good instructable though, thanks for offering it.

[P. J.]

Thanks for posting, but I'm slightly mystified.
I can point that  when doing a spot of local shopping, as opposed to mountain biking,  but with a load far exceeding your 4lbs, that from a standstill position, if  I want to swing the bike 'round in an opposite direction, it can feel like the back wheel has been glued to the ground and if I'm being careless the resulting change in equilibrium might cause me to fall over. But it has never actually happened.
With such a load, tackling such things as road-side kerbs, which often have to be travelled over, has to be done with some degree of care if for no other reason then for the sake of the integrity of the back wheel.

This would also apply to side-saddles, so the same air of caution would apply and wearing a small backpack, as you suggest,  would surely raise the centre of gravity, not to mention the problem of landing on the loaded back pack.

It would probably be safe to suggest that most people will carry their shopping with view to being careful not to damage it and the amount of caution needed to do so should be sufficient. Mountain biking on the other hand is another matter.

Other than such minor obstructions such as kerbs, cobbled stones and typical uneven road surfaces I have not fallen off  even on occasions when braking suddenly  lead to  my rear wheel overtaking me.

But, I have only encountered the situation of falling on two occasions, the first was due to ice, but that was because I had tried to take on a low, iced-over kerb from a side angle. the second was on account of been hit head-on one rainy mid-morning, by a motorist who failed to give right of way and claimed not to have seen me despite my big orange jacket, and though my lamp was on.

[sideways]

Great idea! I have two carriers left over from when I had pets. I had considered a small laundry basket, but they aren't as sturdy as the carriers. I have panniers, but they are awkward, as you noted. This will work much better. Thanks for posting this :-)

[P. J.]

Pleasure. It might be worth knowing that if, like the blue base shown, you do not need to cut out a section to facilitate the design of the rack, then what you will have will be surprisingly water tight. That means that in the event of a severe thunderstorm, it'll fill up and not loose a drop... not even overnight. So, an extra hole for run-off might be an idea to consider. On the other hand, you'll notice just how much bits of sand and other stuff is floating about in the air and at least no longer going straight onto your gears. Apart from weekly shopping at the local market, (fruit, veg etc for 2) I once even managed 2 small 20 litres bags of garden compost (approx 15 kgs in total) which just fit without having to be tied down.

[P. J.]

If you have panniers /side bags, you can still leave them on. The only real difference will be in attaching them freely afterwards... but still posible without having to undo the cat thing.