And Then I Got High

I’ve just realised I’ve been living in Nice for almost 2 months now doing some amazing roads and climbs...and haven’t blogged about it. I know! Big oversight on my part. Anyway, I’ll avoid all the ‘filler stuff’ and skip straight to the big one. Today I did the Col de la Bonette. The highest paved road in Europe at 2,715m (8,907ft). Oh wait, what’s that? The Stelvio Pass is 2,757m? Balls. Ok well it’s actually a little loop of road at the top of the Col de la Bonette called the Cime de la Bonette (2,802m) that’s the highest paved road in Europe (the French basically decided to build a little loop just to get one over on the Italians. Good on ‘em), however much to my dismay (ignoring all logic with all the snow around) that was still blocked! So unfortunately I can’t say I’ve ridden the highest paved road in Europe today (but I’ll probably see if I can get away with it until I can go back when the Cime is open...)

Either way it’s a cracking climb. 17 miles and about 5,000ft of ascent (sorry for switching back to imperial-I’m programmed!). I was a little apprehensive of the whole altitude thing, as I’d never gone over 2,000m before and that’s apparently where ‘funny stuff’ starts to happen, so I paced it slightly conservatively. Which actually isn’t entirely true. I paced it over conservatively on the lower sections in anticipation of getting my ass kicked once I passed the 2kM mark (I genuinely had this image of there being a line painted on the road with something like ‘start suffocating now’)-I still wanted to do a decent time! As it happens it wasn’t too bad, maybe I’m one of the those people who don’t feel the effects quite so badly. Although having said that, I did try to lift the pace in the last mile or two and was strangely lacking oomph...altitude or just 1hr 15 climbing in my legs? We’ll never know. I did however pick up a couple of KOMs for the last couple of miles, which I’m pretty chuffed about. Although that is always an accidental thing right ;)

The descent was awesome as well, as I’m sure you can imagine, half an hour of sweeping good quality fast roads. Heaven! I also saw some random Beaver-ish mammals that turned out to be Marmot. I must have seemed quite the ignoramus not knowing they were Marmots, but hey-I live in Wales for half the year normally so give me a sheep and 9/10 I'll correctly identify it.  Apparently it’s actually quite rare to see them (Marmots not sheep); not if you ask me though, I saw about 10 on my way up and down!

I’ll leave you with a few pictures, they speak better than words...

Saint-Étienne-de-Tinée. The bottom.

Going up.

Going up but looking backwards just to keep you on your toes.

Going up and looking forwards but in the 'backwards' direction. Switchbacks see.

I've lost track. 

Getting close to the ass-kickin line.

The top! In the distance.

Had to resist the urge to 'melt' my name into that. If you get me.

The view from the top (Col top) back down where we'd come.

The elusive Cime. I'll be back for you Monsieur!

To the rest of the Alps.

Pro photo bomber.

Mountains. Can't beat em!

Although this came close. Officially Best Ever Pizza. Honestly! Recovery food innit.

Getting out of the car in an alpine downpour to test a prototype. Dedication!

So to sum up: rode a big climb, loved it, got a headache and a cough from the altitude, achieved inner nirvana on the descent, had a massive Reco Pizza (TM), came home. Not a bad day way to use a public holiday!

Ciao.

That 25mm Thing

The 25mm Thing. (originally published December, 2013...reworked slightly now ;)

You’re probably aware that the latest ‘big thing’ in cycling that isn’t to do with disc brakes is the shift towards running larger section tyres. This flies in the face of pretty much all previously accepted racing wisdom and tradition and may be hard for some to accept, but it’s based on hard science. For a given tyre pressure, a 25mm tyre will roll better than an identical one in 23mm section.

So. According to various sources, the long and short of it is that 25mm tyres run at the same pressure generate less rolling resistance than 23s. Simple! Well...in that sense it is. However, we’re not talking like 20w savings or anything like that, really just percentage points. There are a few important points that should be considered:

·         There is variation in rolling resistance within models and even batches of tyres due to the manufacturing processes involved- so- it is possible that a ‘good rolling’ 23mm could generate less rolling resistance than a ‘poor rolling’ 25 of the same model.

·         A good quality 23mm tyre would almost certainly roll better than a lower quality 25mm tyre.

·         A 25mm tyre designed for touring, or designed to be puncture resistant first and foremost (think Gatorskin and the like) will not roll as well as an out and out race 23mm tyre (think Conti GP Supersonic etc) by design. Think back to my posts on TPI etc, there are a lot of contributory factors to rolling resistance.

·         Tyre pressure is critical. You will note that I always say ‘at a given pressure’, because a 23mm tyre pumped up to 100% of recommended pressure, eg 120 PSI, will roll better than a 25mm tyre only pumped to say 80 PSI (or about 67%) of recommended pressure.

·         A 19mm track tubular tyre pumped up to recommended pressure of ~200 PSI will roll better than a 25mm road clincher pumped up to 120 PSI. Not the most realistic of comparisons, but worth mentioning.

It is quite clearly not correct to just say ‘25mm tyres are faster, end of’ as a blanket statement. There is however more behind the shift towards wider section tyres. If a 25mm tyre rolls better at a given pressure, then logically it is possible to lower the tyre pressure and, overall, experience no respective loss in rolling resistance. Lower tyre pressures equal more comfort (which is always nice), and also mean more grip (due to the carcass being able to deform more to the surface of the road-more tread in contact with the ground=more grip). Lower pressures also, considering Boyle’s Law (I think), could mean safer riding for those deciding to risk using carbon clincher rims on big climbs. Allow me to elaborate/go off on a potentially incorrect tangent: 

·         Every beaded (i.e: clincher) tyre has a pressure at which the outward pressure will exceed the force of the bead keeping it on the rim-and will jump off the rim/blowout. Carbon clincher rims suffer from poor heat dissipation under breaking and you have no doubt read the many horror stories of people descending big cols and blowing out/off whatever they were running on their carbon clinchers in the process. Blaming incidents on these on equipment is unfair. It’s not the equipment’s fault-it’s the choice of equipment! Tyres for example are engineered with as much headroom between the recommended pressure to absolute max ‘this-will-now-blowoff-the-rim’ pressure as feasible bearing in mind the other characteristics required for its application. Going back to Boyle’s Law: ‘for a fixed amount of an ideal gas kept at a fixed temperature, pressure and volume are inversely proportional.’ So, if temperature increases for a given volume, so must pressure; hence the known issues regarding long heavy breaking on carbon clinchers. Or at least that’s how I interpret it/remember GCSE physics (please correct me if I’m wrong). So if you insist on taking your carbon clinchers to the Alps/Pyrenees etc then can I suggest also packing some 25mm tyres? You’ll be able to run them at a lower pressure (without going any slower as explained previously), but more crucially will also therefore give yourself perhaps 5-10PSI extra safety headroom. Which could mean the difference between you getting to the bottom of a long descent upright, or not.

Whether or not 25s would have increased in popularity without the concurrent advances in wheel technology pushing wider more aero rims or not is another point worth considering. Wider rims are more aero (or at least, react better in a wider range of wind yaw angles. A.K.A ‘real world not wind tunnel’ riding and so require less energy input from the rider to continue riding in a straight line) and wider tyres fit this wider profile better, ensuring a smoother transition from tyre to rim for the air-so it’s win/win. Would a 25mm tyre be more aero on a ‘standard’ narrower profile rim? I can’t answer that, but what seems obvious now is that it would roll faster than a 23mm version of the same model at the same pressure.

That’s the key to the whole ‘25mm thing’, they are indeed faster-but only in certain situations. If your bike has the clearances to take 25s (sadly my race bike doesn’t...or at least not with any safety margin), then next time you need to replace your tyres, try the same model in 25mm. Go as fast for more comfort and grip, or go faster for roughly similar comfort/grip? I’d take that for something as simple as swapping tyres.

Thanks for reading. I hope that helped you better understand ‘the 25mm thing’, and if it did maybe consider sharing it with others who might be interested? I think it’s fascinating personally, and would like to think I’ve helped people better understand it!