Introduction: Cheap and Easy Bikepacking Handlebar Harness

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About: Riding bikes and making stuff

If you are heading out for your first overnight bikepacking trip there is no need to get a special handlebar bag. Just take your existing sleeping bag, tent, dry bag, stuff sack or pillowcase and attach it to your handlebars by whatever method you have at hand. Bungee cords and boot laces work great, but really any type of cord or webbing will do.

But while this will work, and gives you a chance to see if bikepacking is a thing you want to do more of, you’ll also quickly see the advantages to a purpose-built handlebar bag. Having a floppy bag bouncing around on your handlebars makes steering more difficult, and can be downright dangerous if it hangs low enough to contact the front tire or prevents you from using your brakes. And as the bag bounces around it will wear on your stem and brakes, which can quickly create a hole in both the bag and whatever you put inside it.

The solution to this problem is to use a harness to hold your bag onto your handlebars more securely. There are many ready-made handlebar harness systems, and they are often sold both as a standalone harness or with a matching stuff stack. But it is also very easy, and cheap, to make your own harness that will work with whatever bag you already have. I recently used this harness for a 20-day through-ride of the Arizona Trail and it worked great. This is also a good DIY workshop activity for any group interested in bikepacking that can safely use heavy-duty scissors, power drills, and chisels.

Supplies

1 Krazy Karpet (preferably 48”, but a 36” is enough to make a single harness)

A marker

Masking tape

Heavy duty scissors

Exacto knife

Drill and 5/16” bit (or thereabouts) 

3/4” (or 1") chisel

Hammer

Block of scrap wood to drill/hammer on

1 pattern printed out from one of these pdf files (pick the one that matches your paper)

Attachments

Step 1: What Is a Krazy Karpet?

Our harness will be made using a Krazy Karpet. If you did not grow up in Canada, or the snowier parts of the United States, you might not know what this is. Here is the original TV ad from the 1970s introducing the Krazy Karpet.

This “space age plastic slider” is literally just a sheet of thin plastic. The top-side is just as slippery as the bottom so half the battle was just trying to stay on thing in your polyester snowsuit. Once you managed that you were treated to a terrifying ride with zero-control and no padding from any bumps. Hitting a jump was a great way to end up in the Emergency Room. The only saving grace was usually before you got going too fast it would turn sideways, causing you to spill off and roll down the hill. Good times.

While the original Krazy Karpet brand seems to have disappeared, similar products are still available and at a price barely higher than the originals. Here in Canada the easiest place to find them is Canadian Tire: https://www.canadiantire.ca/en/pdp/turbo-carpet-kids-winter-snow-crazy-carpet-sled-assorted-sizes-colours-0825201p.html

As with most things, they can also be found on Amazon, but (amazingly) at a higher price. If you know of a place to purchase them in your country/area please let me know in the comments. Because they are so cheap they are often, sadly, treated as disposable, so if you live in an area where there is a toboggan hill there is also a good chance that one can be found (or at least parts of one) at the hill after a big snow. A great chance to do a little upcycling.

What is truly wondrous about the Krazy Karpet as a material is it fulfills all three of Keith Bontrager’s criteria: it’s cheap, light, AND strong. A single 48” slider will give enough material for two full-size handlebar harnesses and still give you enough leftover material for other projects (for more ideas see the end of the tutorial). Sure you could source similar plastic sheeting in bulk, but that would take more time and likely cost more money. And with a Krazy Karpet you can be sure that the plastic material will remain flexible across a wide temperature range. However there are a few tricks to working with the material, as I will cover in the next sections.

Step 2: Print Out a Pattern

I have included 3 different versions of the pattern. The full-size one is for a complete harness, but requires a large format printer or laser cutter. Because the design is symmetrical you actually only need one quarter of the pattern, so I have included versions of that for both A4 and 8.5”x11” Letter paper. Print out the pattern of your choice, making sure the dimensions of the print-out match those on the pattern, and cut it out (you may need to use an Exacto knife to cut out the holes, which is a good reason to just print out the quarter-sized version). Laser-cutting the pattern also works great if you have access to one.

NOTE: If you have access to a laser cutter you might be tempted to save time and just laser cut the Krazy Karpet directly. DO NOT DO THIS. Most Krazy Karpets are made from a variant of PVC plastic and laser cutting them will release toxic gases that will harm both you and your cutter.

For this tutorial I will be using the one quarter pattern as that is likely what most people will use. I will also be making a harness for a flat bar, but will show how to quickly adjust the pattern for a drop-bar (or to just make a narrower version).

Step 3: Trace the Pattern

By using the long edge of the Krazy Karpet you can avoid a little bit of cutting and make sure your patterns are lined up. My Karpet had a bit of “grip” texture sprayed on one side so I am using that side – in practice the grip is useless for actually making it more likely that you will stay on the Karpet while sliding, but it does hold the marker ink better than the bare plastic side. Affix your pattern to the Karpet with a piece of masking tape. Trace it with the marker.(Image A)

Flip the pattern over, tape it down, and trace the mirror image of your first marking. (Image B)

Move the pattern to create the other side of the harness. Because the material is slightly transparent, if you have a cutting mat with a grid it can help line up the pieces. But really it is not that important to get things perfectly straight. Tape it down and trace (and if you are smarter than me you will do this in a way that it won’t block the line you need to trace).(Image C)

If you are making a harness for a drop-bar you can align the half-hole in the pattern with the full hole already marked on the Karpet in order to create a narrower harness. (Image D)

Repeat the above step to trace the last quarter.

Step 4: Cut Out the Perimeter

The next step is to cut it out. You will only cut out the outside perimeter of the harness with your scissors. DO NOT CUT OUT THE HOLES. Not only would cutting out the holes be really difficult with scissors, you risk notching the material and making it prone to tearing. We will do the holes in the next step. The material is fairly easy to cut with strong scissors, but don’t use your good sewing scissors as it will dull them.

Step 5: Cut Out the Holes

For the next step you will need to use a drill, hammer, and chisel so you may want to move to a location more suitable for those tools. And before you actually cut any holes you should probably check the location of the holes with your actual bike – especially if you have adjusted the width of the pattern to fit drop-bars. I like having the main mounting holes (the inner holes along the centre line) as close to the stem as possible. For more on mounting see the next section.

Cutting the holes is a two-step process to prevent the holes from tearing under load. First you need to drill out the round ends of the hole. Place the Karpet on your chunk of scrap wood and drill with a 5/16" (or close enough - for this one I used a 19/64") bit. It does not take much to drill through – only a couple of rotations of the bit. Because the material is so thin it will want to ride up the drill bit so it helps to hold the material down as close to the hole as possible. As this will entail you drilling very close to your fingers, a glove might be a good idea. Don’t worry if the edges are a little rough or if the “grip” coating peels off.

The next step is to connect the two holes using your chisel. A 3/4” chisel is perfect, but a little wider won’t hurt. Just be sure to keep your chisel cuts inside the circles created by the drill. We are using the same principle as drilling a hole at the end of a crack to stop it from spreading, so if your chisel cut goes outside the drilled hole you will defeat the purpose of drilling the hole in the first place. For example, I cut it pretty close in the top right corner of this hole. Going a little inside the circle like I did in the bottom right is better.

Repeat for all the holes. It’s probably easier to do all the drilling and then all the chiseling, but whatever works for you. By the end you may be cursing me for putting so many holes in the pattern. Once you're done you can clean the holes up by scraping the chisel over them.

Step 6: Mounting Straps

NOTE: I apologize for using red and green straps as I realize this may make it difficult for color-blind readers. They are what I had. The red straps are the long ones. The green straps are the short ones.

What you will need:

2 long straps for going around your bag. Here I’m using 25” Voile straps (the red ones). 32” would be better as they would allow me to use a slightly larger bag and just make mounting the bag easier (obviously the length of your strap determines the maximum circumference of the bag you can carry), but this is what I had. However, if you don’t want to use Voile straps you could also use 3/4” webbing and buckles. Or even just some cord. The key is it needs to be long enough to go all the way around the bag (don’t just attach short pieces to the ends of the harness as they will eventually fail).

2 short straps for mounting the harness to the handlebar. Here I’m using 6” Voile Nano straps (the green ones). This is honestly too short and makes mounting an exercise in pinch strength; 9” Voile Nano would be perfect. Voile straps are really perfect for this application as you can get them really tight and they are rubber so they grip the handlebar. However similar harnesses from manufacturers sometimes use webbing and buckles. A shoelace wound through each hole multiple times would also work in a pinch.

Foam spacers (4 in the picture) to go between the harness and the handlebar. These help provide some grip so that the slick plastic does not directly contact the handlebar. They also space the harness out from the bar a little bit so it doesn’t rub on your stem or cables (as much, it’s still going to rub!). I had some leftovers from a commercial handlebar harness so used them, but you can make your own out of any high-density foam (i.e. thick exercise mat). A slot for the mounting strap will help them stay in place while you are putting the harness on.

A strap to connect the bottom of the harness to your fork crown. This will prevent the bag from bouncing up when you hit a bump. I just used a spare piece of webbing and buckle I had lying around (and which, as you will see, was too short). A chunk of cord/shoelace would work fine.

A reinforcement strip. I’m using a strip of 1/4” baltic birch plywood. This strip will provide some rigidity to the harness and provide reinforcement for the mounting straps. It should be as long as the width of the harness, and about ¾” wide (needs to fit between the mounting holes). Other things you could use are a dowel, a chunk of ski pole, a piece of copper pipe, a broken arrow shaft, or even just a stick. Just make sure there are no sharp edges that would rub on your bag.

Step 7: Put It All Together

This is really the case where a picture is worth 1000 words. Here is an image of what the harness will look like from the front when it is mounted to your bike.

And an image of what it looks like from the back (i.e. what you’ll see when you look at it while riding).

The key is to lace the main (red) straps so that they never actually pull on the harness, they just tighten up around it. And to make sure that both the main (red) and mounting (green) straps go around the reinforcement strip. If you are like me you will put at least one strap in backwards and have to redo it. Slide your foam spacers onto the mounting straps. The strap to connect to the fork crown can go in whatever hole works best for your bike on the bottom of the harness.


Step 8: Put It on Your Bike

All that’s left now is to mount it to your bike. Wrap the two mounting straps around your handlebar and tighten. You can see here that because I used 6” voile straps I can only use the first hole (and even getting them to that point was a struggle).

View from the front. You can see that this fork crown strap is way too short for my fat bike. On this bike the harness sits nicely on top of the brake levers, but sometimes you will have to adjust it – I even occasionally run the cables “inside” the harness (i.e. behind the bag). Give yourself time to experiment for the best set-up that doesn’t kink your cables.

Strap in your bag and you’re done!

Step 9: Next Steps

Congratulations on making your handlebar harness, now get out there and use it!

If you are looking for a next project for your leftover Krazy Karpet, here's a few ideas:

  1. Make another one for a friend. Bikepacking is more fun with someone else.
  2. Make a roll-top dry bag to go in the harness. Krazy Karpet works great as a stiffener, and it's even easier to make a double ended bag (no need to sew that circle on the end).
  3. Make a matching mud guard for your fork. You probably have enough material to make some for your friends too.
  4. Make a seat bag harness. Here is an example of a commercial one for your inspiration. In the comments the designer even explains using a drill and chisel to cut the plastic sheet (which is where I got the idea to make a matching handlebar bag).