See also: Going Tubeless
It’s not impossible to get a bit cynical about the flood of gimmicky gadgets, products or optional features which modern technology has enabled, not least when associated with ‘adventure’ + ‘motorcycling’. But I believe that for the
• ease of fitting and
• non-interferring redundancy
a wireless Tyre Pressure Monitoring System is a smart idea for your travel bike.
For as long as I’ve been on the road, tyre makers and road safety tsars have harped on about the importance of maintaining correct tyre pressures. They’re right of course: doing so is a major contribution to road safety for the reasons illustrated vividly in the videos below. But modern bike tyres are so good that I’ve often inadvertently ridden on drastically under-inflated tyres for weeks and not even noticed.
Add the fact that on some bikes the valves can be awkward to access with tyre gauges which themselves are hard to read or flakey. Plus it’s all grubby down there and your knees/back are no longer like Nureyev in his prime. Unless you’re a certain type of ATGATT swot, for day-to-day riding it’s all a bit of a faff to check tyre pressures as regularly as they advise. And yet your bike’s other vital signs: oil pressure, battery charge, temperature, lights and even which gear you’re in – are all conveniently lit up right there on the dash.
Tyre Pressure Monitoring System
The problem has always been how to read the pressure inside a tyre that’s spinning around at 1050rpm. Solution: the advent of inexpensive wireless technology. A TPMS is ingeniously composed of two replacement valve caps fitted with pressure sensors which pair and communicate wirelessly with a small watch-sized display mounted where you can see it (or beamed to your indispensable smartphone; right). The TPMS display is either powered off the bike’s battery or is rechargeable in some way, so it’ll work on anything else with a regular Schrader valve.
Result: real-time tyre pressure and even temperature monitoring (right), either full-time if hardwired, or displayed on demand at the press of a button. And best of all, the rechargeable ones don’t interfere with the bike’s systems in any way. If the caps play up, just refit regular ones. They weigh as little as 8 grams so are unlikely to cause tyre-balancing issues at normal road speeds.
Over the years I’ve found DIY as well as other tubeless conversions like Tubliss and BARTubeless have lost air pressure faster than a regular tyre, tubed or otherwise. And this is even when not run at very low psi where the tyre could conceivably ‘burp’ out some air over a bump. With any sort of DIY tubeless conversion, I highly recommend fitting a TPMS; certainly in the early days until you know how good the seal is.
Riding Off Road
As we all know, lowering tyre pressures greatly improves traction on loose surfaces and can transform a bike from a mindless shopping trolley into a hyper-sapient roller blade. But when you lower tyre pressures, temperatures in the tyre carcass soar as it flexes and unflexes on each rotation, just as you get hot exercising because your muscle tissue is rubbing. And as tyres heat up pressure readings climb. (This is why cold tyre pressures should be your baseline). In this hot, rubber-softened state a tyre is much more prone to punctures and other woes.
Off-road I tend to keep pressures as low as necessary but as high as possible. Usually erring on the high side at the cost of a comfy ride, so weary am I of repairing flats on tubed tyres in the middle of nowhere (left).
A TPMS won’t stop punctures but at least you’re able to observe how pressures climb from a cold start and what they’re actually doing on the dirt, so helping eliminate the guesswork of ‘press the valve for 2-3 seconds’ or the nagging feeling of ‘should stop and inflate a bit?’.
This is one worthwhile gadget I wish I’d had on my Tenere back in 2007, if not all my desert bikes over the years. I’ll be fitting one to the Enfield Himalayan running Tubliss all round.
You can buy obscure-brand TPMS kits for your bike off ebay from £30 for the smartphone-only ones.
In the UK and presumably elsewhere, Michelin are releasing a USB-rechargable kit (left) which I’ll be testing on the Himalayan.