Friday, 9 November 2018

Munga Musings - Guest Post 3

Munga musings from a novice - Carlo Gonzaga 

Part 3 of [probably 3]

All the gear and no idea


A decade ago I broke down on a dirt road in Kenya's northern frontier.  This road exits north out of a place called Marsabit in Kenya and winds its way through 250km of sandy corrugated hell before depositing its journeymen in the Ethiopian border town of Moyale.  The cause of my unexpected and soon-to-be-very-expensive mishap was a blown rear shock absorber on my BMW GS1200.  It was hot enough to cook a goat on; leaking like the Titanic and smoking like a recently lit PRASA train.  Earlier in the trip we passed a weighbridge where my steed and I topped out the scale at 422kg.   I tell this story because it may put my Munga equipment choices into some perspective.  On the one hand I have a predisposition to catering for every eventuality while, on the other, I hope I now know better.


I don't think any subject matter in endurance cycling attracts more diverse opinions than the one of what should fill your bags.  Hell – there isn't even agreement on whether you should take bags with you at all.   I have looked at so many pictures of blokes on bikes and bike set-ups that my wife has started checking my browser history.


At the one extreme you have folks like Jeannie Dryer.  If you don't recognise her name, google her before you make a fool of yourself in cycling company.  In 2016 she came second – overall - in one of those epic cycle races that reminded me of that Froome/Sagan breakaway in 2016, or Armstrong vs Ulrich after the knapsack caught his handlebars in 2003.  The Stuff of Legend.  She travels so light that when I saw a picture of her bike I felt sorry for her as she had clearly been the victim of a mugging on route and all her belongings stolen.   Heck, her bike was even missing half its fork.    


When I asked some chaps what Alex Harris would take they jokingly replied, "an earbud".  With true attention to detail, it must be the hollow plastic type – doubling as a straw for shallow puddles of water in the Karoo.    


Look at photos of finishers of the Tour Divide and the Munga.  It's immediately evident that the quickest folks also have the least gear.  Pondering this over your first glass of Pinotage you may conclude that the reason they can carry so little gear is becausethey're the first into the showers at the finish.  Slower riders simply cater for more time on the road, you conclude, packing you third pair of shorts into your seat bag.  However, what if, after your third glass you wonder if the reason they're first into the showers is because they carry so little.   In excel, this would qualify as a circular formula.


Betting and pain

My first attempt at packing my bike saw the scales reach 28kg (the bare-bones bike with tri-bars is 13,9kg).  When taking it for a ride it had the handling characteristics of a six pack of yogurt on a roller-skate.   One way to approach this "what to take" dilemma is to get lists from people that have done similar events and simply see what fits in the bags you've bought.   In fact, Alex provides a handy list that will probably get you through the Munga not wanting for much.    However, if you're like me and are looking in every nook and cranny for small gains to make up for large inexperience and moderate watts, then what to pack is, first, a question of principle.  How much risk am I willing to take and how much discomfort am I willing to endure.


For example, I asked my bike shop what spares I should take.  Among others, they suggested I take a spare tyre.  It's probable that if I pitched up at the start with a tyre slung around my shoulder like an ammo belt in Rambo 182 I would get laughed off the start line.   I am happy to live with the risk of not taking a spare tyre, but can I live with the risk of not taking a spare tube?  One tube or two?  A tube with slime or no slime?   Old school rubber tube or those new lightweight orange tube thingies?   

I need a nap already, but it could be the wine. 


Unless you're a politician there are no free lunches and decisions involve a trade-off of some sort.  This packing dilemma is no different: carry too many answers to 'what if?' questions and I increase my weight, going slower, especially up the hills.  On the plus side, the chances of a terminal breakdown are reduced as I have enough spares to rebuild my bike from the hubs up.  Taking the second feedbag increases wind resistance, slowing me down.  But at least I won't starve to death and have a higher chance of finishing.   Despite all the 'keep it simple' talk I imagine that those that travel light today, traveledheavy once before.  To realise the benefit of getting rid of baggage you must have carried it once before. 


Colin Anderson (that guy that took an 87km wrong turn last year) has had to sew his tyre together with fishing line and a needle to prevent the tube from popping out.  I really thought that only happened in movies with ex-bodybuilders as the lead actors.   The real question to ask Colin is why the hell he thought that carrying fishing line and a needle was necessary in the first place.   Was he perhaps hoping to 'throw a line' at some point?


Then there's the question of how much discomfort I am willing to endure.  Two bibs or one?  A second shirt?  What will I sleep in?  Arm and leg warmers as well as a base layer, making night riding a pleasure?   Will you, like me, ride a full suspension bike on 3" rubber that eats corrugations for starters and doesn't even cleanse the palate before eating sand roads for mains?  My car seats are harder than the ride on my bike.  At the risk of stating the obvious, this decision is highly personal - not in the Malusi Gigaba type of way, but I think you know what I mean. 


How much does money weigh?

I seem to have distilled all the good advice I have received down to a few main objectives when it comes to how to think about gear choices:  reduce weight, manage risk, reduce air resistance, and reduce complexity.


I week or so ago I was out riding with two Munga veterans:  Colin Anderson and Gavin Robinson.  Both have completed a brace of Mungas and Freedom Challenges, among others.  At some point Gavin was having some anger management issues with his pedals and I was struggling to keep up. To slow him down I started rambling, incoherently at first, about how he thought about equipment choices.  Apparently (Colin had to eventually tell the story), Gavin talks to his equipment, asking one simple question: "what do you do for me?".  If the said piece of equipment has only one answer it goes in the bin.  Gavin has even done this during races, shedding equipment as he goes.  In Gavin's world if you're going to make the cut you need to have more than one use.  By way of example:  my space blanket is meant be useful to me in an emergency.  It's mandatory per the Munga rules.  Gavin reckons itsalso good to use in the same way you would use newspaper down your shirt to keep the icy wind out when you descend Ouberg or Baineskloof.   It's also good to sit on:  getting dirt and gravel in your chamois is not recommended unless you plan on standing most of the Munga.  But best of all Gavin reckons that if you hold it above your head it will reflect sunlight and can be used in advanced search and rescue operations when you've had enough and are calling for your mom. 


So, for me at least, having never done an endurance event these seem to be the parameters around which I've made my choices: How much discomfort I am willing to endure; how much risk am I willing to take, and does it have multiple uses.  Then, for each item, my journey went down weight loss boulevard and air resistance alley.   At some point, which I am still busy with, I will make all of this less complicated.   Jeez - this Munga stuff is exhausting.  And this isn't even the riding bit.


Let me humour you, and you me, as I share some of my more recent discoveries about how gear choices impact cycling speed.    


What's a fart worth?

Somewhere in the dead of night I came across some research that indicated that the things that slow you down the most are air, gravity and your tyres.   (Wine and whisky are still under review).  Amazingly, for me at least, they are in that order of importance.  Even on mountainous routes gravity still back ranks air resistance.  This appears intuitive to most.  For me this was new news that required some understanding.


After all, if I was going to cycle the Munga in a cat-suit and a condom over my helmet I should know why. 


So here is what seems to be at play:  when we cycle up a hill the effect of gravity is linear.  That means that, considering no other factors, to go twice as fast up said hill, you will need twice the number of watts through those bastard pedals.  This requirement stays the same regardless of the gradient.  However, if you're cruising nicely on a flat at 15km/h and want to go twice as fast, you will need eight times the power on those same bastard pedals to overcome the wind resistance.   The power needed to overcome wind resistance and wind drag, increases more and more the faster you go.  The same problem the guys at Bugatti had when they built the Veyron:  it requires something like 500hp to get to 200mph and another 500hp to get to 250mph. 


"Not a problem" you say – "I never cycle at 30km/h".  What if, in what appears to be a quite likely scenario in the Munga, you're trundling along at a 15km/h, turn the corner and find the wind is blowing into your front teeth at 15km/h?  Well, mathematically, you would need twice the power just to stay at 15km/h.  From trundle to trouble, with a capital F.     


Part of the reason why the power required is not double, like gravity, is that it's not just the force of pushing through the air that you're overcoming.  As the air flows over your irregular (I'm not judging) shaped body and seat bag, it swirls about, causing a small pocket of air directly behind you that acts like a vacuum, sucking you backwards into it.  This is called drag. You must overcome this drag in addition to pushing the air in front of you out the way.  It's like trying to push to the front at a rock concert – you've got to shove the people in front of you out the way, but as you pass themthey try and grab you. 

In one of Alex's adventures a group cycled from the top of Kilimanjaro (the mountain, not the song).  Speaking to some of them, they all commented how fast they went.  You see, at 6000m altitude there's just not a lot of air to push through. 


Given the flattish profile of the Munga it looks like spending time on being less like a brick and more like an arrow seems to be effort well directed.  Better directed than, for example, only taking half a fork.  According to the chaps that run the wind tunnel at Specialized the difference between having pannier style bags and bike packing bags is a crazy 1.5km/h or 6 hours over the course of the Munga.  Hydration?  you're better off carrying a six-pack in your backpack than on a rack right behind you. 

Want to rock some cool baggies and loose-fitting shirt? – that'll cost you 2-odd hours in the Munga.  The greatest clothing gains seem to be made from ditching the baggies, donning the five-xl race-cut gut-hugging shirt and squeezing into that toit-as-a-tiger jacket. 

Tri bars? If you only use the standard MTB position and your mate uses aero bars some of the time -you mate will be 8 hours into the beer by the time you arrive in Doolhof


Low carb for gear

Having been told all my modest cycling career that 'weight is everything', I weighed everything.  I mean everything. The tape under the tribar mounts.  The additional links of a chain.  I know the weight difference between different types of bottles and have debated the weight difference between polyshorts and a speedo, in the event I may like to swim during the Munga. 


I tossed my old rubber spare tube for a new-fangled orange Tubalito.  Boom! Saved 183g.  Bought a lightweight jacket - another 194g 'saved'.  And that's not even considering the lesser volume and air resistance due to smaller packing requirements.  If I take a spare bib it will 'cost' me 194g.   Before you go out and splash 1 billion rand on those carbon seat rails and a Cannondale lefty here's some food for thought, which I was happy to hear: 


Weight has a larger impact on more mountainous routes (not new news).   Even then it is only significant going uphill on gradients above 4% (good news for the Munga).  On the flip side you go slower down the hills! (I can live with that).  But here's the data that really focussed my mind as to whether I should empty my bank account in search of everything carbon;  


For every 1kg saved, I will improve my time over a (not flat) 100km course, by about 1 minute.  Specifically, a 1kg saving over the Munga course will theoretically yield an 11-minute saving.  Only 11 minutes. 


I did double check that.    


I have nonetheless continued to put my gear on a diet.   The problem I have discovered is that my bike weighs 13,9kg and, unless I convert it to a unicycle, that is a difficult number to change.  At the last weigh-in my bike, gear, and H20 was 24,4kg.  That's 10,5kg to play with.  Of that 10,5kg, water is 3,7.  If I include the very necessary containers that stop the water from spilling into the hot Karoo sand, that number increases to 4,7kg.  Given that water seems to be important on the Munga I only have 5,8kg of stuff to work on reducing.  A 2kg reduction, thereby gifting me 22minutes potentially, would require I shed nearly 35% of that weight.  Seems like a tough ask to me. 


So, armed with this new information I have decided to pack my 3kg espresso machine with me – I figure I'll easily make up the 33 minutes extra by staying awake longer. 


This doesn't mean weight is not worth reducing.  It's just not the most important thing.  If this data is even half right, and I have no reason to believe it's not, better gains can be had by losing some of my own weight (which I've done lots of); changing my aerodynamics from that of small country cottage and changing my tyres. 


Why do tyres resist so much – aren't they meant to roll?     

The effects of weight and air were intuitive, but I was not alive to the specifics.  What was less intuitive in this journey of mine has been the effect of tyres.  Specifically, how small decisions can steal watts quicker than a window washer in Sandton.   My Stumpjumper has 27,5" rims and comes off the shelf with 3" wide black stuff.  It's got more grip on the gravel than some of our honourable ministers have on reality. 


Each tyre weights 1000g before the LBS has added Stans to each.  Every person I've met asks me if they're difficult to 'turn'.  Enough people asked me this question that I started to get a little anxious at not having a cogent answer.  They didn't 'feel' difficult to get up the hills.  I started digging a little. 


Looking at rolling resistance data it looks like:  the more air in the tyre, the less watts it takes to keep the tyre rolling.  That sounds right.  What I didn't realise is that its about 4W-6W difference between 1.7bar and 3.8bar of pressure, with more watts required at lower pressure.  That difference equates to needing 32% more power to keep a Continental Speedking turning.  So, if you're pushing 150W that's 3% more watts required, per tyre.   That's an enormous time difference over the distance of the Munga.  According the folks at Schwalbe this only applies on tar.  The Munga isn't on tar.  Oops. 


Their view is that a tyre with a lower pressure can adapt better to bumps in the surface and sinks less when the surface is not sealed (like tar).  The principle at play is that the more a tyre deflects the more energy it absorbs, instead of transferring that energy into forward motion.  A very hard tyre will deflect more than a softer tyre.  But here's the real interesting discovery – wider tyres have less rolling resistance than narrower tyres.  (I've included the explanation on this in a picture below).  But wait… there's more:  you can run wider MTB tyres at much lower pressures than the equivalent 2.3" tyres.  It's a sort of two for the price of one deal:  Wider tyres are better.  Lower pressures are better.  Wider tyres run at lower pressure.  #hellyeah


My last 5600-odd kilometres have been done on 3" or 2,8" rubber at 0,8 to 1,1 bar.  I'd like to say I knew when I chose this tyre size in February that it looks, on paper, to be perfect for the Munga. But I can't – it was luck.  I'll take what I can get.


You don't enjoy the Munga

At this point if you're still reading you're probably an A-type personality or having a kak day at work.  I've heard many people say that this is OTT, OCD and even a "FFS – just ride your damn bike".  I'll admit, none of these conclusions are untrue.   I'm all the above and probably should just ride my damn bike.  But I'm curious. I like to question 'universal truths' and 'conventional wisdom'.  In short, I like to understand why I do stuff.   Perhaps in time I'll be able to "just ride my bike". 

For now, I am in love with the inspiration this crazy-ass Munga race has given me to learn more about a hobby I enjoy.  I haven't read this much in years, nor tried to understand mathematics and nutrition, nor the effects of training stress scores on my fatigue and form.   What I have learnt is that despite appearing OCD this stuff does matter in endurance races.  Tyre choice and pressure; aero bars and riding position; better fitting clothing and some understanding of the where and why I carry stuff on my bike, matter.


When I spoke to Mike Woolnough those few weeks ago I got to talking about "how I plan to enjoy the ride".  He picked up a slice of focaccia, had a bite, and in a sort of hushed tone said something like "you don't enjoy the Munga – its uncomfortable.  It's hard."


When I finish this years' Munga I want to know I could not go one minute faster.  I don't want to regret spending an extra three hours at waterpoints or wondering why I stopped when I didn't need to.   I am sure my arse will hurt in my single bib, with no backup.  I don't want to pitch on the line and not have a view why I have 3" rubber at 1bar.   I accept I will get much of this wrong, but I take responsibility for that.   I plan on racing the Munga.   Where I come relative to the other 149 competitors is inconsequential to me - as long as I leave everything inside of me on the dirt roads between Bloem and Paarl.   


The Munga does not start in Bloemfontein.  It starts in those last waking hours of many nights.  Those thoughts become etched into your eyelids slowly taking shape as you commit, pull out, recommit, ask permission, pull out, swear a little, pull out one last time, and finally, commit.  Alex maps out 1100km of the journey.  The rest of the journey is up to you.   T.E. Lawrence didn't have the Munga in mind, but he may as well have:

"All men dream, but not equally. Those who dream by night in the dusty recesses of their minds, wake in the day to find that it was vanity: but the dreamers of the day are dangerous men, for they may act on their dreams with open eyes, to make them possible"


For those who I'll see on the 28th November, at noon, we will be the dreamers of the day.  Avanti!


That's an Arkel seat bag with frame.  Weighs 661g.  The bag on top of the seat bag is a 2L camelback bladder in an insulated bladder bag with a pipe than runs along the top tube and appears between the tri-bars.  The Bedrock bag on the bottom of the down tube holds a 1l bottle.  Bag and bottle are a bit heavy at 411g.  The only upside is that the bag keeps it colder for about 6 minutes longer and I don't have to wipe the cow dung off it before drinking.  

There are two Revelate feed bags on the bars.  I'm not sure what will end up in there just yet.  At 65g each they're light but probably not great for wind resistance.  Have my Garmin 800 and an iPhone (not in picture) for music and to record myself in general states of hysteria while riding.  A 22000mah battery pack will keep my iPhone and Garmin charged the entire Munga.  Not having to take anything off my bike to charge at charging stations keeps things much simpler.  Also, less chance of forgetting the things behind.  The tri bars are Red Shift, from the great chaps at Gravel and Tour.  If you haven't ridden tri-bars (like I hadn't) prepare for pain until your body gets used to it.  Transact patches for your shoulders should come with the tri-bars.  

The spares I'm taking.  The only thing not there are some extra bolts, a cleat and screws and the rubber O-ring that keeps my light and Garmin on.  These all fit inside my down tube and weigh 745g.

Given the lack of gnarly descents my Specialized Butchers will miss the trip to Cape Town.  These Rocket Rons have a great mix of puncture resistance and very very low rolling resistance due to the tread pattern.  I have tested one set for 2900km to date and had zero sealant leakage and had to plug 5 or so punctures, with no more required than just jamming the plug in.

In my search for weight gains I did weigh a flip flop with a cleat.  Weight is better, but heel support was lacking.  Didn't make the cut. 

After permission to release the mixture formula its:  squeeze the tube of nipple cream and the bactroban (supiroban generic) in the tub.  Mix well.  Apply to body.  I haven't had a need to apply directly to the chamois.   The Anethane is for when you're getting into emergency territory as its a topical anaesthetic.

From the Schwalbe website.  The most cogent explanation I found around wide tyres and their rolling resistance.  This happened to confirm what Alex spent much time trying to explain to me.  Apologies for arguing with you Alex. 

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