Monday, December 18, 2023

Musings of an ebike customer


When riding the hills recently, upon which I was unceremoniously dropped, I decided that given my advancing years and the apparent immortality of my riding companions, an ebike might be on my radar screen. Of the bikes I considered, all had some common characteristics. All were Class 3 (offering pedal-assist only, which ceases when the e-bike reaches 28 mph in the USA) with carbon fiber frames, mid-drive (bottom bracket) motors, semi-wireless or fully wireless electronic gear shifting, disc brakes and wide tire clearance. All were way on the wrong side of $10,000. There is a myriad of choices throughout the industry; most major manufacturers now offer ebikes and the numbers increase by the month.  However, they are extremely sophisticated (that is, complicated) devices and I believe that maintenance and servicing are issues for the foreseeable future. For this reason, I focused on Trek and Specialized because both are excellent brands which have (hopefully) adequate service outlets in Austin.

 Marketing hype requires the regular introduction of something new and therefore, by implication, better.  Both mountain bikes (1970s) and gravel bikes (2000s) were introduced long after off-road events such as Yorkshire’s legendary Three Peaks cyclo-cross race which dates from 1961 and which used bikes which had many characteristics of their two-wheeled descendants. And now the term “endurance bike” has now been introduced. All this pigeonholing is questionable. Bicycle designers have been experimenting for over 150 years with different frame geometries and components to meet the needs of different riders. “The Birth of Dirt: Origins of Mountain Biking” by Frank Berto is a persuasive account of this phenomenon and should be mandatory reading for anybody interested in the history of cycling, whether a mountain-biker or not. 

 Confusing terminology results in a challenge for any prospective customer and it is necessary to delve into the specifications of a particular bicycle to ensure that you end up with something appropriate to your needs. Using today’s vernacular, I was looking for a “road” bike with limited “gravel” capabilities. This idea is proving popular and some manufacturers are pushing their machines’ dual-purpose versatility, even at the high end.

 Both brands push their own components, Bontrager (Trek) and Specialized with the main exception being the drivetrain which is either Shimano or SRAM, Campagnolo having disappeared from the US market.  I assumed that the e-technology and the hydraulic disc brakes of both brands are equally effective and, in any case, I am ill-equipped to evaluate any subtle mechanical differences between them. Frame geometry is ostensibly more relaxed on a gravel bike but here too, I assumed that the models that I looked at would probably work for me.

 Manufacturers have experimented with various suspension systems initially designed for mountain bikers such as Trek’s IsoSpeed rear pseudo-suspension system (located at the junction of the top tube and seat tube) or Specialized’s Future Shock (front suspension located below the handlebar stem). These innovations are now appearing on road bikes.  Other components such as dropper seat posts have appeared. These allow for quick adjustment of saddle height without requiring getting off the bike but would seem to have little value on a road bike.

 So, what is left to think about? 

 Component dimensions. Both Trek and Specialized pre-determine these for a given frame size. For the perfect fit with a custom frame, one would usually evaluate steer-tube length/bar height, stem length & [WH1] rise, crank length, handlebar width etc. etc. To these, add tire width, depending on the bike’s intended use and saddle width, depending on your anatomy.  The irony is that, except for Trek’s Project One, these multi-thousand-dollar bicycles offer little or no true customization. The only way to make this happen is to take off the stock parts, purchase the components you want separately and then have them installed by the retailer.  The steer tubes come pre-cut from the factory so they can only by shortened ….. goodbye handlebar height.

 Gearing.  There are several methodologies for expressing gear ratios. The one I usually use is calculated thus: divide the chainring size by the sprocket size (both determined by the number of teeth), then multiply by the bike's wheel diameter in inches. The latter is a function of both rim diameter and tire size. Some formulae also factor in crank length but that only changes the results by very minor amounts. One of my custom 10-speed road bikes has a 53/42/30 triple crankset and the other has a 50/34 compact double. My cassettes have varied from 11-23 to a 12-28 resulting of high gears of approximately 120 gear inches and low gears of about 28 gear inches.  However, the introduction of ebikes changes this dynamic as with the pedal assist, the need for very low gears is somewhat mitigated. The most radical innovation in the mountain-bike gearing arena is the widespread introduction of single cranksets with chain rings of 40 teeth or lower and mammoth rear cassettes with up to 50 teeth. These set-ups, colloquially known as a “one-by,” are now migrating to road and gravel bikes.

 Tire width.   Back in the day, I used to run 19 mm tires at 120 pounds pressure. Ouch !!!  Now the trend is towards wider tires at much lower pressures. Road tires are typically 28 or 32 mm whereas gravel tires are in the 35 – 45 mm range. As a roadie, one important issue for me is not how wide a tire I can get on the supplied rims but what the safe minimum width is.

 Handlebars.  Road bike bars are usually quite aggressive in geometry. Gravel and endurance bikes have a lower drop and sometimes use a flared design, not dissimilar to the Rene Herse “randonneur” style. Without trying them, I do not know if I would have a strong preference.


 Historically, the company has used the following nomenclature: S-Works = Premium line (carbon frame manufacture and high-end components), Turbo = ebike, SL = Super Light and EVO = short for Evolution which represents a design or technology upgrade, usually, but not always, applied to their mountain bikes.

 On their current website, Specialized listed three ebikes of possible interest to me: (1) the S-Works Turbo Creo SL, identified by the manufacturer as a road bike, (2) the S-Works Turbo Creo SL EVO, identified as a gravel bike and (3) the most recent addition, the S-Works Turbo Creo 2 which claims to be a road/gravel “combo”.  All three are 1x12: Specialized no longer offer any high-end ebikes with a double chainring.

 The Creo SL and the Creo SL EVO are being discontinued, replaced by the new Creo 2 which, as mentioned, is being sold as a road and gravel multipurpose bike. However, I think that the Creo 2 strongly leans towards the gravel community: it comes with a single 44-tooth chainring, a 12-Speed 10-50 cassette, flared handlebars, and a dropper seat post. It is supplied with massive 47 mm tires although the rims will accept any in the 28-47 mm range. The drivetrain is SRAM’s fully-wireless Red eTap AXS.  Thus Specialized no longer offer a high-end, road ebike although some dealers still have a limited number of the now discontinued Creo SL and Creo SL EVO models.


 There were two bikes on the current Trek website that were of interest: (1) the road-specified Domane+ SLR 9 and (2) the gravel Domane+ SLR 9 AXS.  In the company’s nomenclature, the Domane is the series name, the + indicates an ebike, SLR = "Super Lite Race", the 9 indicates a carbon frame (c.f. the 7 which is aluminum) and lastly, AXS (= “access”) which is SRAM's component integration system that connects the electronic components and software.

 The two frames are identical in terms of frame construction and geometry. Both use the same motor, the TQ-HPR50 which is rated at 50 Nm, 250 watts maximum continuous rated power and 300 watts peak power. The wheels/rims are the same though the SLR 9 comes with 32 mm road tires whereas the SLR 9 AXS comes with gravel-suitable tires of 40 mm width. Both models come tubeless but the rims can take tubes.

 The primary difference between the two is that the Domane+ SLR 9 uses the semi-wireless Shimano 2x12, Dura-Ace Di2 drivetrain with 52/36 teeth chain rings and an 11-34 cassette. The Domane+ SLR 9 AXS uses the fully-wireless SRAM 1 x 12, RED XPLR eTap AXS single drivetrain with a 42-tooth chain ring and a 10-44 cassette.

 Trek’s Project One boutique program offers full components customization: chainring size (within a 36 – 46 range on the SLR 9 AXS), steer tube length/bar height (limited), stem length, crank length, handlebar width, tire width, saddle width etc. can be individually specified. And there is a huge range of color options, for a price.


 Given that my “need” for an ebike is not urgent, I will wait to see what the manufacturers introduce for the 2024/2025 model years.  If either Specialized introduce a true road version of the S-Works Turbo Creo 2 and/or Trek introduce a “one-by” 1x12 version of their Domane+ SLR 9, then the market will become even more competitive.



Monday, August 19, 2019

Trailblazer Lee Wheeler: about 140 medals and still counting

Some years ago, when we lived in San Antonio, I was lucky enough to be introduced to a group of cyclists who called themselves the Trailblazers.  It was an informal group whose great strengths were the diversity of rides and the accompanying social activities.

One of the founders was a gentleman called Lee Wheeler and it soon became apparent that not only was he a cyclist par excellence but he was older than most in the group. More on this later. 

Lee was born in 1928 but did not really started riding as an adult until he moved to San Antonio in 1975 when he was already almost 50. However, he was a runner and bike rider back in his childhood. In his own words: “I spent most of my childhood in Paris, Texas.  During Elementary School I had several jobs.  I delivered 132 newspapers in the early morning, before school, on a bicycle I bought for $18.00 at $3.00/ month.   I delivered telegrams for Western Union on my bike and also worked for Paris Drug Store delivering prescriptions to senior citizens on my bike. My Mother and Father died when I was very young and then I lived with my Grandfather.   I was a wild teenager in high school and to prevent my incarceration, I was sent to live with an uncle in Dallas, who was an ordained minister. He tried, I tried...... then I joined the Navy and my life changed”.

The tattoo on his leg also tells part of Lee’s story.  During his days in the US Navy, he got at least one mildly risqué tattoo on his leg. Inevitably, when he embarked on his 27-year career as a high school science teacher, he always had to wear long pants so as to not expose his young charges to the famous tattoo.  That need for discretion did not apply to the Trailblazers.

But back to Lee’s cycling.  Over the years, he has successfully participated in numerous Senior Games cycling and running events at both the regional, national and international levels.  This has taken Lee to many competition locations not only throughout Texas but also to Louisiana, Florida, Virginia, Arkansas and Utah. Along the way (as of 8/1209), he has picked up an impressive collection of cycling medals; no less than 46 gold, 46 silver and 46 bronze. In 2018, Lee won two more golds in San Antonio (still averaging about 14 mph) which qualified him to compete in this year's nationals in Albuquerque.  Now 91 years old, he placed first in everything he entered: the 10 and 5 kilometer time trials and the 20 kilometer road race. 

In 2017, Lee was inducted into the Texas Senior Games Hall of Fame, a fitting tribute to this quite remarkable man, one who I am so proud to call a friend. 

Thursday, July 20, 2017

Non-circular Chainrings: Paradise or Placebo?


Several of my riding companions have recently experimented with non-circular chainrings. As an anecdotal observation, most of them report a performance improvement and none have reverted to their original circular rings.  There have been several well-publicized results on non-circular chainrings in the last few years, most notably the Tour de France wins by both Bradley Wiggins and Chris Froome. Interestingly, however, Tim Kerrison, head coach at Team Sky, claims that credible research that has been undertaken is inconclusive. The question then arises: are these scientifically proven benefits or a placebo effect?  This article attempts to summarize current thinking with the disclaimer that I have not yet tried non-circular rings myself.


The idea is very simple: design and orient chainrings that allow the rider to spend less time in the least powerful parts of the pedal stroke, when the cranks are vertical, and more time in the most powerful parts of the pedal stroke, when the cranks are horizontal to the ground. That is, minimize the negative effect of the so-called “dead spot” which is the point at which the cranks are vertical and neither leg is generating any significant power. 

The single parameter that captures this idea is known as “crank angular velocity” which remains relatively constant throughout the pedal cycle with circular chainrings.  A non-circular chainring varies the crank angular velocity within the pedal cycle which, in turn, alters the time spent in each segment of the pedal cycle. To translate this into practical terms, the chainring should have a larger radius at the stronger segment of the pedal stroke and a lower radius at the weaker segment.

Bicycle engineers have been aware of the dead spot for over a century; non-circular chainrings were first tried back in the 1890s. The most notorious experiment in recent years was with Shimano’s Biopace rings (1983 to 1993). Recent studies claim that the downfall of Biopace was caused not by the shape of the rings but by their orientation.

There are several parameters that are relevant in non-circular ring design: the number of teeth, the “eccentricity” of the rings (the ratio of the major axis to the minor axis) and their orientation relative to the crank arms (including adjustability that allows rings to be “dialed-in” to the specific rider and bicycle set-up).  The various manufacturers of non-circular rings, for example Rotor, OSymetric, Bionicon and Absolute Black, all put their own particular spin (is there a joke there?) on the different variables.


There have been a myriad of papers written on the subject, not all of them independent and unbiased.  Researchers have examined the physiological and performance differences between non-circular and round cranks on numerous occasions. Though there are some that report improvements of up to 6% with non-circular chainrings, a majority have concluded that, for efforts longer than one kilometer, there’s not much difference between round and non-circular chainrings. None reported a decreased performance. Additionally, not all authors are even agreed on the appropriate output parameters to be measured:  speed, power output, lactate threshold, heart-rate etc. 

In support of the use of non-circular rings for high-intensity events, an IJSSE study based their conclusions on a 1 km time trial study over a six-week period, using eight competitive male cyclists and triathletes using Rotor Q-Rings. Performance measures during the time trial were based on time to completion, speed and power output. In addition, physiological measures (oxygen consumption, heart rate, blood lactate were also monitored over the time span of the study.  The authors concluded that the Rotor Q-Rings provided a positive effect in the time trial and speculated that they could also prove beneficial in criterium-style racing events or at the end of a road race in which bicycle racers typically pedal at similar intensities and durations as the 1 km test. (“Effects of Chainring Type (Circular vs. Rotor Q-Ring) on 1 km Time Trial Performance”. Christiane R. O’Hara et al. International Journal of Sports Science and Engineering. September, 2011).

However, more recently, The Journal of Sports Science and Medicine published an article which documented extensive testing for blood lactate, power output and oxygen consumption but concluded that non-circular chainrings did not produce statistically significant differences over round ones. (“Physiological Responses during Cycling with Non-circular Chainrings and Circular Chainrings”. Alfredo Cordova et al. Journal of Sports Science & Medicine. May, 2014)

Studies at the University of Utah, while not challenging the fundamental premise behind the use of non-circular chainrings, addressed the issue from the perspective of joint-specific kinematics. The author concluded that use of non-circular chainrings did not either enhance or compromise joint-specific (collectively, the hip, knee and ankle) performance in trained cyclists. (“The Influence of Non-circular Chainrings on Maximal and Submaximal Cycling Performance”. Chee Hoi Leong. Department of Exercise and Sport Science, The University of Utah. December 2014).


The anecdotal evidence in support of non-circular chainrings, though not compelling, is certainly intriguing. Perhaps they are at the same stage of development and general acceptance as clipless pedals, integrated shifters and mountain bike suspension were in their early days …. innovations that are now regarded as de rigueur.

Nevertheless, it would appear that objective scientific experimentation in support of the use of non-circular chainrings is somewhat lacking and there is unquestionably no measure of consensus among the various researchers.  At the end of the day perhaps we need to just accept that even a placebo has the potential to offer a significant performance gain.

Some challenges

If you decide to give non-circular chainrings a try, be aware that:

·       Not all of the various manufacturers’ non-circular rings fit all cranks. Be sure you understand your crankset’s spider pattern, bolt circle diameter etc.
·       All front derailleurs are optimized to work with round chainrings and some degradation of mechanical performance might result with non-circular rings. In this regard, front derailleur fine-tuning might a tad more finicky.
·       The risk of dropping a chain appears higher with non-circular rings so consider installing a chain catcher on the front derailleur.
·       Because non-circular chainrings change the angular velocity of the crankarms and thus the power transmitted to any power-meter strain gauges that yu might use, any historical power data from your prior use of circular rings cannot be compared to the data set from the new rings. 

Tuesday, September 6, 2016

Left Turns – Let’s Do Better

 Of all the cycling maneuvers that I watch in our group rides, one of those that we consistently perform poorly and often dangerously, is making a left-hand turn.  Ideally, in a group, these are best lead from the rear but first let’s look at the basics.  To start with, watch this short video.

Here is a diagram that summarizes the points in the video.

 Note these important points:
  • When making a left turn on a two-lane road, you will first need to move safely to the left of your lane. On a four-lane road, you will have to move across more than one lane.
  • Never attempt to make an abrupt left turn directly from either the right-hand side of a two-lane road or from the right-hand lane of a four-lane road.
  • Before you change your lane position, you must first look back for traffic. Turn your head to look even if you have a rear-view mirror. No mirror will show cars at your side and physically looking back alerts traffic approaching from the rear.
  • Extend your left arm to signal that you want to move to the left. Wait a couple of seconds, then look back again to check that the drivers have slowed down or moved aside to make room.
  • Assuming that the drivers behind you have time to react to your signal, they should let you into line, allowing you to proceed with the turn.  Do not change your lane position until you're sure that the driver has made room for you.
  • Your signal alone doesn't make it safe to change lane position. Only a driver’s affirmative response to your signal ensures your safety.
  • In high-speed traffic, drivers coming up from behind may not have time to react to you. In that situation you must wait for a gap in the traffic before you move to the left.
  • Traffic typically comes in waves, if you find yourself in a gap a block or two before your left turn, merge left and use the left lane for a few blocks. This is perfectly legal and much easier than trying to negotiate through a wave of traffic.
  • Maintaining your left-turn hand signal, position yourself in the middle of the intersection as necessary and continue to make the left turn when there is an adequate gap in oncoming traffic or when it has been stopped by a stop-sign or traffic light.
  • Make sure you turn first into the right-hand lane of the new route and then into the shoulder or bike lane if one exists.
  • If you cannot safely maneuver yourself in the left-turn position by the time you reach the intersection, don't force the situation. Continue straight through the intersection and make your left turn at the next intersection.
  • It's also perfectly okay to make a left turn as a pedestrian. Stop at the far right corner of the intersection and, when clear, walk across the road to where you can safely re-enter the traffic flow.

 As mentioned above, in a group setting, changing lanes in preparation for a left turn is best orchestrated from the rear though I acknowledge that this requires training, practice and knowledge of the route.  Watch this video to get an idea of this concept:   

Saturday, June 11, 2016

No-drop bicycle ride descriptors

Note:   Typical speeds below are for a flat ride with little or no wind. Actual averages may vary and will often depend on which riders are in the group.  To maintain average speeds, certain stretches will usually be somewhat faster.

E – Social rides for anybody wanting a very relaxed pace. Suitable for recreational riders, beginners and families. Ideally has more than one ride leader. Typical average speeds less than 11 mph. 

D - Advanced-beginner riders who still feel the need for some mentoring/support or for more experienced riders wanting a leisurely outing.  Typical average speeds in the 11-13 mph range.

C – Intermediate level of intensity for newer riders wanting to complete more challenging rides or for stronger riders wanting a relaxed pace.   Average speeds probably in the 13-15 mph range.

B – Moderately intense. “Upper intermediate” level for fit riders with a few years in the saddle.  Typical average speeds in the 15-17 mph range.

A – Intense. Brisk pace for experienced, self-confident riders.  Might be hilly and/or could involve skilled pace-line riding. Typical average speeds in the 17-19 mph range.

AA – Very intense; fast and/or very hilly rides for fit, experienced riders. Might sometimes involve skilled pace-line riding. Typical average speeds in excess of 19 mph. 

Ride Category
Average Speed (mph)







Thursday, January 14, 2016

Defeat the Thieves !!!!!!

Do you want a near thief-proof security chain for your precious bicycle?  Are you willing to pay a little extra and, perhaps more importantly, are you indifferent as to its weight?

 Then proceed as follows.  Buy 3 or 4 feet of Pewag 3/8" square security chain (about $12 per foot excl. tax/shipping, Westech Rigging is one supplier), one Abus 82/70 keyed padlock (about $20 excl. tax/shipping from Zoro or similar) and some heavy duty canvas.  Wrap the chain with the canvas and secure at each end with vinyl electrical tape or similar. 

When locking your bike, if at all possible, run the chain through the rear wheel as well as the frame.  If you are using this for your auto bike rack, get enough chain to go through frame + both wheels.  If you are using it for hanging out at SXSW on your mountain or city bike, you might have to take your chances with the front wheel.

BE WARNED: my 3-ft version with lock weighs about 6½ pounds !!!!   

Thursday, November 5, 2015

Dogs and bicycles usually do not mix too well

Most dogs are normally friendly but seem to go nuts when exposed to a moving bicycle. After all, they are descendants of predators who chased down prey for a living. Some are just being naturally playful but others are, at best, protecting their territory or at worst, out for the kill.   The negative consequences for cyclists can vary.  You may collide with the dog, which could bring you down or you might lose control and fall trying to evade the creature. It’s possible (though less likely in my opinion) that the dog is trying to bite you and, if it successful, the bite could also have serious consequences.

In terms of evasive action, there are many choices but it’s important to realize that there is probably no “one size fits all”. The dog’s intentions and behavior, the road, the traffic conditions and others things make every situation different and will require split-second evaluation and judgment on your part.  So, what are your options?  In all instances, slow down.  By doing so, you increase your control of the situation. In the case of oncoming dogs, it’s even more important that you slow down and be prepared to stop as there is a very real risk the dog may misjudge your speed and turn in front of you into your path.  Ignoring the dog or dogs might be the best thing if you are absolutely sure they are either going to stay where they are or at least remain on the side of the road. 

The average dog can sprint about 19mph and some manage considerably faster speeds.  Out-running them is rarely the right thing to do. Not only is it unlikely that you'll always be able to outrun the dog but panic sprinting means you will probably not be paying close attention to the road, traffic and your fellow riders.  Some people believe that yelling loudly works but many dogs are unlikely to respond to commands and it might aggravate them further.  In fact, one rider I know is a dog whisperer; he uses a very calm voice with any dogs and it seems to be quite effective.  Spraying with water bottles is of limited use; most dogs quickly realize that the water is of no danger to them. They might even find it refreshing.  

Trying to hit them with the pump might be effective but is fraught with risk. It’s probably not a good idea to be gesticulating wildly while at the same time trying to control your bike. Similarly, unclipping and trying to kick the dog is risky and the dog might just see your leg as an easy target.  Stopping and putting your bike between you and the dog or dogs is probably effective. You then feel more in control. In most instances, the dogs will simply continue to bark and then hopefully give up and go home unless you're actually on their land.

There are various devices on the market such as the Ultrasonic Dazer which emits high frequency sounds that supposedly makes dogs very uncomfortable.  They might work under some situations but not always. Let’s hope the dog is not old and deaf.  Similarly, some people recommend air horns that come in small can-sized versions and deliver a very loud burst of sound that hopefully shocks most dogs.

Pepper Sprays have a lot of appeal to many riders. Various versions are available; the most popular one is but is supposedly more powerful. You have to get the dog directly in the face for it to be effective so use the spray variety, rather than the “cloud”. Be sure not to spray yourself.

If you encounter unrestrained dogs and if the worst happens, these are steps you and/or your riding buddies should take: 
  1.          Seek medical attention for any injuries. Keep good records.
  2.          Take photographs of any injuries or bike damage.
  3.          Gather information, including the location of the dog's residence and the names and addresses of any witnesses.
  4.          Familiarize yourself with any local animal ordinances. There are some in many counties and most cities. Recognise that some are directed more to either preventing dog abuse or rabies control rather than protecting other road users.
  5.          Notify local animal control (usually city or county). This is very important even if no accident happens. If they take no action on the first report, they might on the second …... or third.
  6.          Consult a lawyer if you want to take further action.

 I love dogs and would truly not wish to harm them. In all instances, the problem is not with the animals, it’s with the owners. While there is no statewide law in Texas requiring that dogs be on a leash at all times, many counties and most cities do have laws requiring dogs to be on leash, or prohibiting them from being unrestrained when off the owner’s premises. Unrestrained dog are considered a public nuisance and with few exceptions, courts have ruled that violating such laws can be the basis of liability.