Monday 13 August 2018

Rollin', Rollin', Rollin' !

Here I go again... There are many things about bicycle touring that I have found to be nothing more than myths. My last blog I talked on luxuries, and how a little extra weight can make your trip more enjoyable, rather than weight weenying because the extra weight slows you down.

Today I want to chat about tyres and another, I don't know the term for it, myth creeping in. I hear a lot of talk about rolling resistance. I don't know where this originated, maybe Audax or Randoneau riders with bike packing set ups. For touring, really? Rolling resistance! Now I get it on a roadie, rolling resistance is a big thing. Although for the average MAMIL I have to question it.
Honestly, you want to load your bike up with thirty something kilograms of weight then want to worry about rolling resistance???

When it comes to tyres for touring there are only two factors you need be concerned about. 1. Comfort, 2. Durability. Anything else is just woolly fluff and poppy cock.

Comfort is a big thing, and it is well known that the larger the tyre, the more comfortable the ride. Now I'm not talking specifics in regards to diameter. It doesn't make that much difference whether you run 26", 27.5" or 29"/700C rims, although I do think a larger rim size has it's benefits. But the width of your tyre plays a major part.

When I had my Trek Domane 5.2, nothing less than 25 mm tyres went on it. My track bike was different, I only had 23's fitted to it. But, just before I sold the Domane I squeezed 28 mm tyres on it. I didn't think you could make an awesomely comfortable bike any more comfortable. I was wrong, the one size extra in the 28's made such a big difference. I think that if I bought another road bike it would have to be fitted with 32 mm tyres and disc brakes, maybe a new Flying Machine (dream, dream, dream).

There's plenty of scientific proof to show that narrower tyres do not offer significantly less rolling resistance over wider ones. We see this as major players in the sport are increasing tyre sizes. Now of course this is to a point. Tread patterns, TPI (Threads per Inch), tyre compounds all play a part in this. Now, I'd have to think that a 2" wide tyre would offer more rolling resistance than a 32 mm tyre.

But when touring you want comfort, more so than less rolling resistance. Now, it's not just width that plays a part in comfort. Again, it's a combination of width, pattern, TPI and compound.

A mountain bike tread, for instance, may be comfortable on the trail, but can be damn annoying and uncomfortable for long periods on the road. Vibration sets in, and it just shits you off, and they can be hard work to pedal on the tar. A road tyre, although great on the road can be unstable and unforgiving on a trail. So a combination all terrain tyre may offer a better scope.

A higher thread count means the fabric is thinner, more flexible, comfortable, and yes, offers less rolling resistance. The rubber compound on the outside of the tyre is mainly added as a protection for the fabric, and grip. A softer tyre with a 120 TPI is far softer and more compliant than a tyre with 60 TPI. Add that with a softer compound on the outside you have on smick tyre. Well, in the perfect conditions, anyway.

But although a tyre with a higher TPI may be more comfortable, they do have a tendency to be less durable. A 120 TPI tyre is more likely to more easily damaged that say, a 60 TPI tyre.
When I first purchased my pride and joy it came with Clements XPlore MSO's which are a fantastic tyre. So much so that I replaced them with the same brand and specs...or so I thought. It seems that the newer tyres are a 60 TPI tyre compared to original 30 TPI tyres. My first trip on the newbies saw a piece of steel run through the tyre. Well it would've happened anyway, the puncture wasn't the issue. Problem is that it not only punctured the tyre, it sliced it so, that I had to repair it with a patch on the inside. Something I don't think would have happened on the older heavier tyres. This is the conundrum we as bicycle tourers face...comfort or durability.

But this is where size can matter. A wider tyre at a lower TPI can be as, if not more, comfortable than a narrower, more compliant tyre. If I could I would rather have the 30 TPI Clements on the Kona than the 60's simply because I have noticed a big difference in wear rate. Actually, if I could, I would love to squeeze some 2" tyres on it, but they won't fit with the guards on. This is the big reason I chose the Kona Sutra over the Trek 520 and the Wayward Cape York, wider tyres with guards.

This is what you have to work out for yourself, the balance. My recommendations are that you don't go above a 60 TPI tyre unless you are doing strictly asphalt roads that are in good condition, and even then with load etc, well... The heavier tyres are more likely to have a better puncture resistance, and a far less likely to suffer damage from dirt roads, or roadside debris.

Now that I have said this, the last thing you want to do is to go to K-Mart or Big W and buy a cheap $20.00 tyre thinking it will last. Yes, it will be hard compound, and likely to be a low thread count...BUT...you get what you pay for. A cheap tyre like this will offer little comfort, little grip and is likely to start cracking in the walls a little down the road. Tyres and bar tape are two things I will pay extra for. But having said that, there are plenty of bargains out there, and there are plenty of other brands rather than Scwalbe that are perfect for touring. I suggest that you get a decent tyre and go for the largest you can safely fit on your bike. Don't skimp, at the same time don't pay through the roof. Work out what sort of riding you intend to do on your trip and buy accordingly to that.

When touring you're on a holiday, rolling resistance, and other roadie minded thingies, should be the furthermost things from your mind.
Buy for comfort and durability.

Cheers guys, and as always, ride safe.

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