Health, Fitness and Training

The number one question I get asked when riding my fixed gear bike is “Is that a fixed gear?” The number two question I get asked is “What gear are you riding?” With todays modern bicycles carrying 20+ gearing options that are selectable at any point in the ride without getting off the bike or, in the hands of a proficient cyclist, even slowing in speed, this is a great question. It’s also the first question I ask myself while setting up my fixed gear bike for a ride. And if I pick the correct gearing, that number one question gets asked later in the ride with a surprised expression because I’ve so smoothly integrated into the pack that it was only after a particularly fast stretch of road where anyone with the option to shift to a higher gear (lower cadence) would have – only I didn’t! Just like it took me some time to become proficient riding a fixed gear bike, it has also taken me some time to get better at selecting “the perfect” gear for my fixed gear rides. I’ve written this article hoping to shorten your learning curve in finding that “perfect gear.”

But first, let’s agree on the language we’ll use. I’ll be talking “gear inches” – a language older than the bicycles of today. “Gear Inches” originally was simply the diameter of a Boneshaker’s or Penny Farthing’s front wheel - relevant because these bicycles were driven by pedals directly connected to the front wheel – just like the “Big Wheel” of childhood days. Racing penny farthings were made to order and “the best bike” was one with the largest diameter wheel that would “fit” one’s inseam – short people were at a decided disadvantage! So ride a penny farthing with a 54” diameter front wheel, and you were riding 54 gear inches. Then beginning in 1885 on the road, and in the 1920’s on the track, the Penny Farthing was replaced with the “Safety Bicycle” (today’s design) with its roller chain connected front and rear gears and pneumatic tires. And ever since then, most people have been confused by the term “gear inches” – but not you, not now! Because now you understand that “gear inches” relates today’s bike to a penny farthing by taking into account the benefit of using gearing on smaller wheels. By selecting different front and rear gears on a chain drive bike, one impacts the number of rotations the rear wheel makes with each revolution of the pedals. For example: using a 27” wheel with a 42 tooth front chainring and a 21 tooth rear cog results in having each revolution of the front chain ring turn the rear cog (and its attached wheel) twice resulting in 2 X 27” = a 54” effective wheel diameter (gear inches). Same as riding a 54” wheeled penny farthing – only safer!

So to recap: For a safety bicycle, Gear Inches (GI) = (Wheel Diameter) X (Chainring / Cog). And now we get into the final level of confusion about Gear Inches… Different Wheel Diameters are used in calculating GI! Traditionally and in most scientific data published on track training programs a 27” wheel diameter is used. This is the language I’ll use when discussing gear selection. A Gear Chart provided by our friends at Bike Central illustrates typical fixie road gearing choices  (To download a copy click here):

To ensure improved accuracy in your cadence training calculations (and very conveniently available in the excellent iPhone “Bike Gears” app) we will also translate the traditional GI (Std GI) into the modern language which uses one’s actual wheel diameter to calculate GI (My GI). Why bother to calculate a second GI you ask? Because selecting the “perfect gear” is a function of matching your ride’s speed to your targeted cadence window and /or capabilities. Just like when we were kids tearing it up on our Big Wheels, once we select our GI, we’ve established the size of our “Big Wheel” and our speed becomes a direct function of how fast we turn the pedals - our cadence. And the true size of your wheel is a function of the wheel size, tire size, inflation pressure, your weight, and weight distribution (bike position) – all very individual properties unique to you and your machine.

Now the math part. Since speed is (distance / time) and the distance covered by each revolution of the wheel = wheel diameter X Pi, we can quickly calculate our cadence knowing the GI (the theoretical wheel diameter for a cadence of 1 rpm). Remembering that there are 12 inches in a foot, 5,280 feet in a mile, and 60 minutes in an hour we get: Cadence,rpm = (Speed, mph X 5,280 X 12) / (GI X 60). Thankfully we have spreadsheets today and access to iPhone and internet applications that take care of this math drudgery allowing us to focus on our objective - selecting the best GI for our specific training purposes. A snapshot of the Excel spreadsheet I use has been provided here to serve as an example. (To download a copy click here.)

This example shows a bike with an 82.75 inch roll out, 46 tooth chainring, cogs available with 17 – 20 teeth, and my current cadence zones. Note: the spreadsheet allows one to personalize the inputs shown in bold blue font. The five cadence zones listed guide the selection of that “perfect gear”:

1. P, Minimum – is the lowest target cadence when under power. P, Minimum is an important consideration to ensure knee health. This becomes a factor when climbing hills and spending extended times riding into a headwind. Some can handle a cadence of 50 rpm while I, with patella chondromalacia, can get by with 60 rpm for short periods, but must maintain 75 rpm for expended periods, to maintain healthy knees. Your low target cadence is usually the go – no go test as to if you’ll ride a fixie that day. If my cadence + speed (power) objectives puts me in a GI who’s P, minimum speed exceeds my capabilities for hills on the route and/or extended pulls into the headwinds of the day, I either change my speed objectives, or ride the geared bike. To reiterate, I’m using the fixed gear bike to improve my cycling by increasing my cadence and biomechanical efficiencies – not to put my knees at risk nor to spend extended times at low cadences – I’ve been doing that on a geared bike for years! So in this example, I decide if I’ll be able to aerobically maintain 13.5 – 15.9 mph for extended periods and 10.8 – 12.7 mph for shorter stretches (that may be at the lactic threshold) before deciding to ride the fixie and, if so, selecting the GI.
2. P, Cruising – is the target cadence window while under power. This zone is important because it represents a totally anaerobic zone wherein we are working on our form and increasing our average cadence – the “cadence sweet spot” we talked about in December’s article. The speeds in this zone shouldn’t represent any max effort, as the idea is to have the average speed of your total ride fall into the lower part of this zone while the flat road, no wind scenario has you seeing the mid to high end of this zone. Your average target cadence is typically your improvement objective or a known comfort zone which you want to match with your targeted speed (average power output) to meet your ride's objective, be it recovery, fat burning, or endurance. You will establish the base range of this zone on with your first fixie rides by keeping track of your average ride speeds and taking note of your speeds while in your “comfort zone”. With time, this cadence window will increase. For this example, the “cadence sweet spot” falls in the ranges are 95 rpm - 105 rpm which represents speeds of 17.1 – 22.3 mph. Hmmm, sort of covers the majority of the Portland Velo Saturday ride group speed splits doesn’t it? Another reason I love this club!
3. P, 5 minute – is the max cadence maintainable for 5 minutes without going anaerobic. This zone is important in two areas. A) On individual rides, intervals into this zone will help increase your lactic threshold as well as to increase your cadence window. B) On group rides, this is an important consideration as your geared “friends” will, on spirited occasions, exceed the “stated” speed “limit” of the ride for anywhere from 3 – 10 minutes, and if you’re not prepared to match that pace for at least 5 minutes, you’ll find yourself totally blown and soon alone! (Of course if it’s the Signature Saturday Portland Velo Ride, one can always drop back to the following group - if pride allows.) This cadence is also very improvable for a given speed. For example, when I first started riding a fixie, I couldn’t spin the pedals with any level of power above a cadence of 100 rpm. So I’ve vastly improved, but still have far to go. The entry standards for the German National Track Team require one to be capable of 240 rpm while riding rollers. Sort of humbling. So for this example, P, 5 minutes represents speeds of 21.6 – 25.4. This factor is of primary importance when making group riding GI decisions. As you can now see, to a fixed gear rider there's a big difference between groups that hold 19 mph on an extended flat vs. one that averages 19 mph but ranges between 16 and 23 mph over the same route!
4. P, 15 – 30 seconds – is the peak cadence obtainable while applying max power for a short distance. This zone is important for short burst interval training for those working on their sprinting capabilities. This cadence at a given speed (power) is also dramatically improvable. Improvement in this zone will also increase your lower cadence windows. In this example, GI selections will result in speeds of 25.2 – 33.9 mph. Initially this work is done from within your P, Cruising window but can be adapted to begin from a standing start later in the season when working on standing starts. Another humbling factoid: reportedly, Australian track athletes racing at the elite level can apply maximum power at cadences of 180 – 200 rpm.
5. Max – is the maximum cadence one can handle and still maintain control of their body and bicycle. This zone is quickly reached while descending hills. Much faster than this and you have the feeling that at any second your screaming thighs will be torn from your hips and with your feet still clipped to the ever accelerating pedals will commence to beat you viciously about the head in retaliation for the pain you’ve inflicted upon them! Yep – scary times indeed. In this example these speeds represent 32.4 – 38.2 mph. With this as a limiter, the delight of a 40 + mph descent will have to wait for another day when riding with coasting capabilities. The knowledge of this limit is used to ensure I don’t get myself into a situation where additional “runaway” speed will push me above this limit – something most easily tempered sooner in the descent than later! My max – 193 rpm. Didn’t make me feel like an elite Australian Track star at all – but it did about put me “down-under”!

General rules of thumb for selecting ones “perfect” GI are:

• Fixed on the road is typically split between a standalone training gear of 60 - 65 Gear Inches and a "hang with the pack" gearing of 69 - 74 inches. Give or take an inch.
• Fixed on the track is typically split between a warm-up gear of 69 - 72 inches to a race gear of 86 - 105 inches depending on power capabilities and the event itself.

In this article we are focused on GI selection for road fixed gear cadence training. The key to selecting the perfect gear for the day is in establishing your target cadence ranges. “Target ranges - what targets?" you ask? So do I every time I head out on a fixed gear ride. And sometimes I get it right, and sometimes I get it wrong. But that's part of the fixed gear experience / fun / love! Like lasting love, selecting a gear inch requires obtaining balance in order to make for an enjoyable ride. Unlike the complexity of love, with its many variables, a fixed gear inch balance is simply one of cadence and speed (power). Key elements to consider are one’s capabilities for that day, the ride’s terrain, the impact of the wind conditions, your cadence training objective, and the riding style of the group (if it’ll be a group ride). So let’s put it all together and pick a GI using the above example / information.

• For individual rides this time of year I love the 62. The two main factors impacting this selection is that I’m spending significant time in the gym working on leg strength which tends to tire and slow them down, and we frequently get 10 – 15 mph winds which on my winter routes translates into 50% of the ride being into headwinds. The 62 allows me to work in a comfortable speed (power) zone (17.1 – 18.9 mph) which enhances leg recovery while reestablishing a reasonable P, Cruising cadence window. Additionally, I’m able to take advantage of the tailwind to work on higher cadence drills with reduced stress to my legs. All this without losing the benefits of the fixed gear ride as I’m able to maintain the 12 – 15 mph into the headwind on hills without going lactic or dropping my average cadence excessively. This is also the gear I started riding fixed, so even though I’ve “graduated” to higher GI’s, I’m still using it heavily. Looking back, I would have done well to start with a 59 as doing so would have increased my capability to ride fixed on those windy days of winter with my, then, lower cadence capabilities - thus accelerating my cadence improvement journey.
• For group rides this time of year I usually move up to the 65. I tend to ride fixed with the 19’s and theoretically I could stick to the 62. And theoretically the 19’s should hold 19 on a flat road with no wind. But the reality of the fantastic weekends we’ve been enjoying this year, the generally improved physical condition of the 19’s participants, and the 19’s general “friskiness” has resulted in 65 being a better selection. With the 65 I can manage an 18 – 19 mph ride average and hang on when they occasionally ramp it up to 23 mph for extended periods as the 65 gives me a P, 5 min of 22.8 mph.
• Come summer, the gym workouts drop to maintenance levels so I begin using the fixie for adaptive power work. For individual rides I’ll use the 65 in early summer, switching to the 69 for flatter group rides and individual workouts later in the summer for peaking during the track racing season.
• I save the 73 for evening fast group rides during mid to late summer days when I’m feeling “the rage for speed”. You know, those evenings where you’ve had a bad day, you’re wound so tight you’re a danger to anyone slow or stupid (and they’re everywhere!), and you know the best way to feel better soon is to rip the legs off your cycling buddies!!!! What? You don’t know? Um, neither do I – Oh, yes – I just heard about some sick-o feeling that way. Uh, I never use the 73 on the road… and defiantly not with my friends! J

In conclusion, your final gear inch selection is determined by your current capabilities, the route you're taking, the weather's impact, the group (if any) you're riding with, and your training objective. After that, it's time to dance with what you brung and have a blast doing it! And that's part of the joy of fixed gear riding. The pure simplicity of it all...

I hope this helps you find that one, perfect gear. I’ve enjoyed bringing this set of fixed gear articles to you. If you have any questions related to fixed gear riding and/or additional ideas for future articles you’d like to see, please let me know at the next Portland Velo ride or drop me a note. Thanks for reading and I look forward to seeing you down the road…

- Gary Meinhardt