Budget Bike Tech is a new column here on BikeRadar, focused not on the latest high-end gear and accessories but on cheap and clever tips, tricks and upgrades that cost virtually no money at all. Improve your riding and improve your ride – just don't go broke in the process.
This week we're looking at Tyvek. This amazing stuff made by DuPont is thin like paper, flexible like fabric, waterproof and windproof. This makes it a perfect material for protecting your feet in moderately cold conditions.
Simply take an old race number or shipping envelope, trim it to fit, and wrap it around your socked foot from about the front of the ankle forward. It doesn't have to be pretty since the Tyvek will be invisible once you're done. Just make sure you've obscured all of the mesh panels in your shoes as well as the sole vents, if there are any.
Once your foot is wrapped (a single layer will typically do), slide it into your shoe and make sure to wiggle your toes around thoroughly before tightening down the straps. Tyvek is highly protective stuff but it doesn't stretch so you want to make sure you push the material out to the edges of the toe box so as not to affect the fit.
We've been successfully using this strategy all winter and combined with thin wool socks, our feet have stayed reasonably warm during road rides just below 10°C (50°F). The Tyvek material has virtually no volume so it doesn't affect shoe fit and is easily packed in a jersey pocket or saddle bag, plus it's durable enough to reuse nearly ad infinitum. Moreover, you still have access to your shoe straps and buckles for on-the-fly adjustments.
Keep in mind that this technique isn't all that effective in wet conditions where conventional booties would be a better choice and that Tyvek isn't very breathable so it's a good idea to leave at least part of your foot uncovered for ventilation, especially on longer rides.
Unless you're particularly generous with the coverage, you won't get any protection for the front of your ankle this way, either. Otherwise, though, this has proven to be not only an effective alternative to lightweight booties, but one that costs almost nothing.
If you've done it right, the Tyvek will block off all of your shoe vents but will otherwise be invisible (you can just see a bit of red from the Tyvek scrap we used peeking through the mesh around the toe)