Tuesday, May 26, 2009

Gearing for the Hills!

I just got back from my TWiley Sports Training Camp weekend in Lake Placid, NY. After observing many of the athletes "climbing the hills", over the holiday weekend, I realized that MANY of the athletes were climbing in gear combinations that were MUCH too hard for them. In other words, the athletes were mashing up the hills at low cadence rather than spinning up the hills at higher cadence. With the exception of probably Jan Ullrich, former Team T-Mobile, Tour de France fame...(and Lance Armstrong adversary)...there are NOT too many people that can mash their pedals up a hill effectively/efficiently. Simply put, many triathletes ride MUCH too hard up the hills and wonder why they either bonk on the bike, or die on the run....or worse...BOTH! But what I found more interesting is that some athletes simply had no choice on which gear combinations to choose...they were by default in the easiest gear combination (albeit too difficult to push/pedal for them) while climbing- the little ring up front (ring=chaing ring), and the big ring in the back.

Before I continue, I'd like to define a few terms like: big ring, little ring, cassette, crank arm, cog, compact crank, etc. so we're all on the same page. Your bike has gears up front (where your pedals are) and gears in the back (on the wheel). The gears up front are composed of two chain rings (simply called rings): the big ring and the small ring. The big ring normally has 53 teeth and the little ring (right next to the big ring) has 39 teeth. (The number of teeth is usually stamped on the ring..if you can't find it, count the teeth). If you have what is called a "Compact Crank", the big ring will have 50 teeth and the small ring will have 34 teeth. In the rear you have ten rings (10 speed bike) that we call "cogs" or nine cogs (9-speed bike). These cogs make-up what is called a "cassette". The smallest cog (in the back) is normally comprised of 11 or 12 teeth. The big cog (in the back), is normally comprised of 23, 25 or 27 teeth. So, if I have a 10 speed cassette in the rear and it has a 12 tooth small cog and a 25 tooth big cog, we call that a 12-25 cassette...pretty simple huh? In-between you have 8 other cogs. For a 12-25 cassette, your cogs may include: 12, 13, 14, 15, 16, 17, 19, 21, 23 and 25. The only other thing I want to mention is the crank arm. The crank arm is the bar that runs from the center of the big ring in the front of the bike to your pedal. Most standard crank arm lengths are 172.5mm. For taller athletes they are 175mm in length and for some shorter women, they are 170mm.

Ok, now the important stuff. We already know when we climb a steep hill we want to be in an easier gear combination. Remember we said, small ring up front, big cog in the back is the easiest gear? Well, what if you're already riding in the 39-25 gear combination and it just isn't easy enough to push. Or, you want something a tad easier. What are your choices? You have three: a) select a smaller chain ring combination up front. Instead of a 53-39, you can go to a 50-34 (Compact Crank) combination. Or, maybe you don't want to change to a Compact Crank (most are expensive in addition to labor). You have choice b) you can change the cassette in the back from a 12-25 to say a 12-27. Or perhaps, you'd like to chose option c) reduce your crank arm length or even add a "granny" gear (which is a third smaller ring up front). Reducing your crank arm length will increase your cadence and put less stress on the knees. Or maybe you want to do all three (little drastic I'd say).

Here's a good example of an athlete who could probably use a gear change for hill climbing. Just keep in mind that this example is an extreme case where the race is a "hill climb" race. We're going to use our fearless leader from Camp Wiley, Todd Wiley, as an example. Todd did a hill climb on Monday, May 25th from the bottom of Rt. 86 in Wilmington to the top of Whiteface Mtn. I'm not quite sure of the elevation gain but I do know it's an 8 mile trek of nothing but 9% grade (which is steep) hill. Todd was riding in his 39-25 gear combination (that is small ring up front with 39T) and big cog in the back with 25 teeth. Todd was turning his pedals over at 70 rpm (cadence) and producing an average of close to 300w (which is BIGTIME watts) which propelled him at 8.5 mph. (Ask Todd if he was hurting) Now, the question is, would a 39-27 gear combination have allowed him to ride a higher cadence (thus saving his legs- for the bike and run- that's IF he had to run afterwards.) and still produce the same speed at a lower (or same) power output? Absolutely! If Todd was able to increase his cadence to 80 rpm, in an (easier) 39-27 gear (same power output), he would have averaged 9.3 mph- almost 1 mph faster. That's over 5 minutes savings to the top of Whiteface Mountain. How about a compact crank? Again, absolutely. If Todd kept his same 12-25 cassette and changed the crankset to a Compact Crank (50-34) his new gear combination would have been a 34-25. If he were to choose that and ride at 80 rpm, he would have gone almost 1/2 mph faster...or a 2.5 minute time savings to the top.

If you're thinking about changing any of the aforementioned on your bike..email me, and I'll compute the time savings for you...based on the cycling gearing charts that I have. Then, I'll tell you what I recommend..and you can go to your favorite local bike store and ask them what it will cost to add a Compact Crank to your bike...or change a cassette...one specifically for the hills like a 12-27. Don't forget to test ride the cassette in the hills BEFORE you buy it. I'd say if you have a 11-23 or 12-23 on your bike now...change it without reservation. Remember, it's MUCH easier and cheaper to swap a cassette out than it is a Crankset/Chain rings. And, nothing wrong with having a few cassettes to choose from based on the race layout.

Last thing, in case you're wondering. Why doesn't everyone just put a Compact Crank on their bikes? Well, (besides the price tag) just as there's an advantage going uphill, there's a disadvantage on slight descents or downhills. By changing to a compact crank you'll lose 2 mph at 100 rpms on the slight descents/downhills. That might not sound like much..but if it's a long gradual descent..it adds up.

So, get out there and hit the hills..experiment with your gearing...save your legs for the hilly courses...ride faster up the hills...have more fun! Coach Rob

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