Category Archives: Tyres

TPMS – a good idea

Updated Summer 2020

Tubeless Conversion Index Page
Michelin TPMS review and my special offer

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:
• price
• ease of fitting and
• non-interfering redundancy
a wireless Tyre Pressure Monitoring System is a worthwhile addition to your bike, whatever you do with it.

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: inexpensive wireless technology. A TPMS is ingeniously composed of two replacement valve caps fitted with centrifugally activated pressure sensors.

They pair wirelessly with a 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, even a pushbike.
Result: real-time tyre pressure and even temperature monitoring (right). And best of all, the USB rechargeable ones like the Michelin-branded one I tried, don’t interfere with the bike’s systems in any way. If the caps play up, just refit the old 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 gradually lost air pressure faster than a regular tyre, tubed or OEM tubeless. 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.

Tyre pressures increase with elevation as ambient pressure falls, but they also drop as temperatures fall. For every 2000 feet (600m) you climb, the pressure will increase by 1 psi and will fall by the same amount for every drop of 4°C (10°F). But as temperatures naturally drop with elevation, things kind of balance themselves out.

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 influxes much more 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 valve for 2-3 seconds’ or the nagging feeling of ‘should I stop and inflate a bit?’

You can buy obscure-brand TPMS kits for your bike off ebay from £30 for the smartphone-only ones. About £50 seems a good price for a decent one. Here’s an Advpulse review on a hardwire Cyclops TPMS (above left) which sells in the US for $130. Cyclops aren’t tyre specialists, they just sell gadgets and a near-identical looking kit can be bought on ebay UK for about half that price (above right).

A TPMS is one gadget I wish I’d had on my Tenere back in 2007, if not all my desert bikes over the years. I fitted Michelin’s one to my all-tubeless Himalayan and semi-tubeless Africa Twin in 2020. Read the review.

XSR 700 Scrambler – final mods

XSR 700 Scrambler front page

My XScrambleR sets off in a month for Morocco and, bar some luggage, is ready to go. Don’t think I’ve ever had a bike ready so far in advance.

Using some left-over or unused components, I fitted a Tuturo Chain oiler which I still think is the simplest and most effective way of getting this messy but necessary job done. It is, of course, especially handy on bikes without a centre stand where hand oiling the chain is a particular faff.

For luggage I’m going to use some simple Kriega Duo 36 Throwovers again, as I did last year on the KLX in Baja. The great thing with the XSR’s underpipe is that it’s right out of the way of luggage but bags still need something to stop them swinging into the wheel and chain. In the spirit of the Chouinard RURP, I’ve come up with RURTS (Realised Ultimate Reality Throwover Stay) an ultra-minimal side rack. The weight is taken over the saddle; the slim stays help locate the bags. If their reality ultimately turns out to be too realised, another stay from pillion pegs to the rear flashers will fix that. I’m sure they sell broomsticks in Morocco.

Once the holes were drilled the RURTS were another 10-minute roadside job, but lacking anywhere better than the kerb to work, I weakened and got my LBS to do the rest of the heavy jobs.

Shock
The new wheel on the front has raised the bike 30mm, and the fork preloaders may help it stay that way. I was looking for a way to achieve a bit less than that on the back – partly with a taller tyre and partly with a longer shock.
The OE shock is basic; it’s fine for very normal riding but only has preload rings. They are found used on ebay in their zillions. I preloaded it on the first run, but found it lacked any rebound damping to control it.

The OE shock is 310mm long. I was looking for a shock with rebound damping that started at that length but had extendability. Looking at the usual suspects, only the Wilbers 640 Blueline could be specified with that feature for a reasonable £512. All it is is a chunky thread and nut at the bottom of the shock below the red rebound knob, and which can be unscrewed (lengthened) to a pre-set point then locked out. Rocket science it is not, but you need to remember that 10mm on the near-horizontal shock adds up to more in actual seat height. Pythagoras will know exactly how much, but when my Wilbers arrived I maxed it out and sent it to the shop.

Doing it this way makes the shock/bike more sellable later, as it can be wound back down to the standard 310mm XSR height. In fact this whole XSR build, including front wheel swap, is fully reversible. No one need every know.
For once in my suspension history, I’m going to endeavour to set the static sag before I leave. It’s a bit tricky alone, but there are instructions on how to do it all over the web. I dare say it will need some tweaking on the road as it beds in, and I’ll sure miss the Hydraulic Preload Adjuster of my previous Hyperpros, but there we are. As it is, C-spanners keep Elastoplast in business and come free with the shock.

Tyres
I could have tried something new from my do-it-all category, like a Mefo Super Explorer, but only Heidenau K60 Scouts came in a range of sizes which sort of included the XSR; a still ridiculously fat 170/60 17 72T was delivered for £97 from Germany, and a 100/90H-19 Catspaw (not Scout) from the UK for £61. Looking at it now, the rear looks a bit lower profile than I’d prefer, but there was no 170/80 in 17.

The nearest K60 was 150/70 17, but as I was dropping from OE 180 width, 150 (over an inch slimmer) looked too much of a change for the rim size. Best of all, these retain the tubelessness (which reminds me, need to get some Slime in).

Actually, I think I need to address that stunted sidestand now the bike sits at least an inch higher. I could drill a hole through the foot and bolt on a block of wood or HPDE. How shit would that look? Good news is used MT-07 stands go on ebay from 20 quid. Weldy-mate Jon might be persuaded to hypnotise it and make it grow an inch, and while it’s out slap on an 5mm sandplate underneath; it will look like it was made that way and ought to have the strength to take a lifted wheel if I have tyre troubles.

Other than that, my LBS fitted some Oxford Hot Grips for me (£50 ebay). This is the first time I’ve actually bought a set; usually they’ve come with the bikes I’ve bought. and for UK commuters are a no-brainer. Along with my screen, my Barks and my Powerlet jacket, I simply cannot wait for the December ride back across Spain.

Tested: Mitas MC23 Rockrider tyre on WR250R

A weekend of WRing in Wales

WR250R 4000-km review
WR Introduction
WR250R Stage 1
WRing about in Wales
WR250R ready for the desert
Morocco 4000-km trip report, 1–9
Fuel log

I haven’t been trail biking in Wales since my 20s. Makes me wonder what I’ve been doing all these years. Part of the reason is I’ve not had a bike worth riding up there, and then there’s the issue of untangling where you can ride legally. Desert biking can spoil you, but Wales gets a lot more inviting with a light and pokey WR250R and knowing the right people.
Dan and Dave were on my 2007 Algeria tour along with their own trips to all corners of the globe. John, an old mate of theirs, works at the Yamaha Off Road Experience near Llanidloes, and generously offered to take us for a ride out.

We vanned up to Llani, lubed up the bikes and rode over to Geraint Jones‘ hill farm where the Yam school is based. Back in the late ’70s when I was dirt-bike mad, I remember Geraint Jones (left, old pic) was ‘Mr Maico’. He was to enduros what Graham Noyce was to motocross, Barry Sheene to GPs and Martin Lampkin to trials.
In amateur hands the big Maicos he rode had a reputation for being hard to handle. I remember the red devil machines flying overhead as I floundered about during the nearby Plynlimon Enduro in 1981 aboard a KLX250 – the original sheep in wolf’s clothing.

As I recall in Street Riding, I was so slow they were literally packing up as I rolled over the finish line. And if you ever wondered what happened to those red devil machines, this is an interesting read from our man, Rick Sieman.

The benefit of riding with John from the school was that he knew the lanes, which ones would suit the day’s weather and the groups’ abilities, plus he had special access to trails in the adjacent Hafren Forest. Hafren becomes ‘Severn’ in English and a few minutes into the ride we passed within a mile of the River Severn’s boggy source on the side of Plynlimon mountain. Dave was on his third and near-new 690, Dan was on a 100-kilo 350 EXC and John was riding a Yam WR250F, as used by the school. This is a full-on, super-light enduro machine and despite similarities is an entirely different bike from my heavier and less powerful 250R, below left.

For me it was a real eye-opener how gorgeous the Cambrian mountain of northern mid-Wales could be. I’d always considered it a No-Mans’s Land between the better know Brecons and Snowdonia to the north which explained why green laning (using off-road vehicles on unsealed but public roads) was permitted to survive here.

I can now see it as a great destination its own right – a compact Scottish Highlands but without their near-total ban on green laning, and without the rambling crowds of Snowdonia. And never mind the trails, much of the fun to me was cruising the deserted single-track backroads that snaked across the moors – the yellow C roads on the map you could do on any bike.

After Machynlleth, heading up the gnarly ‘Happy Valley’ green lane reminded me my WR was still without a proper bashplate (the OE one is seized on). In the meantime I was amazed how well the unfashionable Bridgestone TW301/302s tyres were managing. These came with the bike in 2008, were refitted by Hyperpro on selling it, and I can say did not miss a beat.
My snazzy Hyperpro suspension soaked up the easy pace too, just as you’d expect, though I dare say I could have refined it by playing with the knobs. Like the TTR250 I used in Spain in the summer, I never wished for more power on the trails or backroads – but then we did cheat by vanning the 200 miles up from London. The good thing with modest power is the tyre won’t spin out readily, but if caught in the wrong gear that WR still had enough to chug its way out – I never stalled it.

After reading so much about them, Dave let me have a quick spin on his 690 (recently fitted with Evo 2 aux. tanks) but can’t say I’m a convert yet. The KTM’s thumping vibration really struck me, soon followed by realising how quickly the sharp brakes and more than double the WR’s power could turn on me if tired or not concentrating. But the bike had a solid feel that even a new WR might not match, and out in the open desert I bet it would be in its element. A quick spin on Dan’s 350 EXC (right) on soft power setting was much more like it, but that bike needs new oil every 1000 miles so isn’t a contender as a travel bike. What I’d like is a 450 version of the 690, but pitched as a less tyre-shredding travel bike. Press the red button if I’ve said this before.

There sure are a lot of gates on the green lanes of the Cambrian mountains. It was rare to ride more than five minutes without doing the gate dance – and sometimes less than a minute. It breaks the rhythm of the ride but they contain the sheep which can easily jump a cattle grid if spooked. The trail north into Dolgellau between Cader Idris and the Barmouth estuary was a notable exception – a good ten minutes riding or more between gates.
We came across a few ramblers and dog walkers who didn’t look too put out – they’re walking along a ‘road’ after all, even if they don’t realise it. And we nearly ran into a big group of lads bursting out of the forest on unlicensed dirt bikes. Damage wise, their impact was minimal and who knows, the new Geraint Jones could be among them, but I bet they’d all rather be legit. Wouldn’t be it be great to have a huge trail park out here where people could roll up and ride round at their own pace, instead of the scurrying around on wasteland or dodging the rangers.

It poured overnight but day two actually dawned even brighter, apart from a well-timed downpour as we ate lunch in Talybont. Either the riding was easier or I was getting to grips with the WR. On rougher trails I did find it hard to ride smoothly; balancing the jerkiness of the engine with the right gear and the rebounding suspension while looking at what’s coming up and steering away from rocks, but this is just the nature riding a light, small-capacity bike at slow speeds. Turn up the wick if there’s room and things would smooth out. After the rain there were some bigger puddles today too. Initially they were a worry as I’d read the WR was prone to cutting out in a splash, but even with the engine note muted in two feet of water, it never even coughed.
I don’t know if it’s been a dry spell – in Wales, what are the chances? – but the ride John led us on was pleasingly free of mud and to me was all the better for it. My recollection of bombing around Rhayader on XTs 30 years ago was plunging into one peaty morass after another which just makes a mess of you and the landscape.

It would be great to do more riding around here on my own, as it’s as wild and extensive as you’ll get in the UK (there’s virtually no green laning in Scotland). But unless you live nearby or do the research, it would be hard to get a handle on which trails are legal and then put together a satisfying two-day route like the one we followed with John. Now of course we have the TET (see map below). Every year more and more green lanes in England and Wales get downgraded to paths. I haven’t a clue which of the trails we did were open to all, but promisingly I only saw one ‘no vehicles’ sign. Lacking a local pro like John, the answer is to hook up with the TRF or join an escorted tour from £50 a day with four of you. That’s just the way it is living in a small, crowded country and why I set off for the wide open Sahara in the first place – and why I’m off to Utah next week!