Technical FAQ: Heart arrhythmias, flying with discs

Follow-up on heart arrhythmias

Dear Lennard,
I think you should share medical advice with caution. Routine echocardiography for a large asymptomatic population is not indicated for screening for “safety.”

Even cardiac stress tests will not predict with any confidence when a patient might have a plaque rupture and die of a huge heart attack (think of former NBC News anchor Tim Russert, who had a nuclear test one month before dying suddenly).

More sage advice would be that anyone who has been sedentary and who wants to go into more serious training should see a health professional for advice, especially those entering middle age. A medical professional can gauge appropriate tests based on the patient’s risks for certain health issues.

For example, the single most common risk factor of sudden death in marathoners is a prior history of smoking and sedentary living.
— Prospero Gogo, MD
Associate Professor of Medicine
University of Vermont Medical Center
Director, Cardiac Catheterization Lab

Dear Prospero,
Thank you so much for your letter. As you said, the best advice is always to see a doctor and follow his or her recommendations. I should not have given a blanket answer for something as individual as human health.

Dear Lennard,
In regards to your reply to Steve about cardiac testing, I have a follow-up question.

I took up cycling nearly 20 years ago and have been an avid cyclist during that time. A couple of years ago I found myself having difficulty keeping up with my long-time group, despite the same or more training. My doc recommended a cardiac stress test and echo-cardiogram. The stress test went fine (and I felt highly complimented by the doc who referred to me as a “high level athlete” in the test results). The echo-cardiogram, however, revealed that I had left ventricular hypertrophy (LVH). Unfortunately, the doc did not know how this could affect my cycling, or if I was in any mortal danger. Apparently, there had not been any comprehensive studies analyzing the risks of athletic activity for somebody with LVH, or at least none up to that time. He put me on meds to lower my blood pressure and that was that.

Since that time, a couple of injuries forced me off the bike for the last couple of years, but I’ve recently taken back up a regular schedule of cycling.

I’ve ordered your book “The Haywire Heart” but was wondering if you were aware of any other research that has been done specific to LVH and its associated risks. Do I need to be worried? Or can I go out and train with the same high intensity that I used to?
— Mark

Dear Mark,
By now maybe you’ve read “The Haywire Heart” and already know what I’m going to tell you. First of all, you ought to seek the advice of a cardiologist who deals with lots of athletes.

You will also have seen in the book that in a masters athlete, hypertrophy of the heart can lead to scarring in the heart, and myocardial scarring is a substrate for arrhythmia. A key finding of a Scottish study of masters athletes that we detail in the book is that fibrosis markers were higher in masters athletes, with more hypertrophy leading to higher levels of collagen chemicals, which are related to fibrosis (scarring).

I don’t think anybody can predict whether you would end up with heart arrhythmia or other problems if you were to go back to training with the same intensity that you used to. What I think can be said from related medical studies is that, assuming you are a “veteran” or “masters” (over 40-year-old) athlete, your left ventricular hypertrophy (LVH) increases the likelihood of developing an arrhythmia than if you did not have LVH, and that this risk goes up with increased demand on the heart through hard training. And whether it is high intensity, high volume, or both that most increases that risk from endurance training, I know of no study that separates those.

Two Scandinavian studies of cross-country skiers that we discuss in the book do not make that distinction. In one study, 509 non-elite 65- to 90-year-old male competitors in the mountainous, 54-kilometer Norwegian Birkebeiner cross-country ski race had 1.9 times the incidence of AF (“atrial fibrillation,” the most common cardiac arrhythmia) than did 1,768 men in the same age group from the general population. And in a bigger study less skewed toward elderly athletes, 52,000 finishers of the Swedish Vasaloppet 90km cross-country ski race followed over a 10-year period showed that both volume and speed increase the risk. Competitors who had completed the Vasaloppet five times were 29 percent more likely to have AF than those who had completed the race only once. And skiers in the fastest group were 30 percent more likely to have developed AF than skiers in the slowest group.

Training for marathon ski races certainly involves lots of volume, and training to be one of the fastest skiers, in my experience over 22 years of cross-country ski racing that includes participating in both of those Scandinavian races, always requires quite a bit of high-intensity work as well. So these studies don’t separate out risks of training intensity from training volume. That is as thorough an answer as I can give you to your questions of whether you “need to be worried” if you “go out and train with the same high intensity” that you used to.
― Lennard

Dear Lennard,
I always enjoy your articles, but the recent one on cyclists preparing going to the doctor with cardiac issue was especially interesting to me, as I’ve had a different but related experience. And, I’m pleased to see articles on this area, as cyclists need to watch out. I’ll try to be brief.

I’m 63 years old and have been back to cycling for about a dozen years. I’m an enthusiast, mostly ride solo, and I’m not very competitive. For a few summers I went on a couple of weekend 100km to 180km per day tours, and would ride around 200km per week. 

Things had been steadily improving over the years, and then things got harder one summer, and I had recovery problems while training in the fall and winter. I always ride with a heart rate monitor (sometimes with power too), and detect recovery issues by a lower-than-expected heart rate during a warmup. That winter, there were more times than usual when I was not able to do my normal day-on, day-off schedule because my heart rate indicated I was not adequately recovered. When the spring came, I started back into longer rides and some intervals. One was going up a gentle but steady hill for about 5 minutes near threshold. When I did it, there was a gentle ache on my left side, nothing special. One repeat and I decided to go home and take a few days off. Repeat, and had the same symptom.

I got an appointment at my GP’s clinic quickly and went through the story with the doctor. I was into a great cardiac center the next Wednesday, and had two stents put in in July.

 It turns out I had the same thing my mother had many years ago when she was my age, plaque buildup in two of the arteries feeding the heart. Not too serious for me at that point, and I probably would not have known for years if I had not been cycling. And, if it had been noticed, I still might not have had the stents put in if I had not been so active. However, if I had not listened to my body, who knows what might have happened one day when I’m out alone on the road.

I’ve recovered well and have been back on the road for a couple of years.
— Jim

Feedback on flying with disc brakes

Dear Lennard,
Your advice in this FAQ included the passage, “… In any case (pun intended), I recommend that you remove the rotors from the wheels for travel. That makes the obvious case (pun intended again) for CenterLock rotors and hubs, rather than 6-bolt ones, so you are spending more time riding and less time screwing around with a dozen rotor bolts.”

Shimano CenterLock rotors have a very high torque recommendation (40Nms or so). I would love your advice as to:

— Recommended torque wrench covering this range (for home use).

— How this can be accomplished by the traveling cyclist.
— Peter

Dear Peter,
To tighten a cassette lockring or a CenterLock rotor lockring to torque, you use a 26mm socket on a cassette lockring tool. While 26mm may not be a common size, it is the same size as some suspension-fork top caps. As for what torque wrench to use, you want at least a 3/8”-drive one (1/2”-drive is also fine) that is rated to at least 60N-m and has a long handle. Here is an example.

When traveling, you’re just going to have to tighten it down with a Crescent wrench to your best guess on the torque, unless you want to lug along a big torque wrench.
― Lennard

Dear Lennard,
Regarding the fellow who had a bike that required fork removal for transport (Flying with discs) but had an internal front brake hose — would a hydraulic quick-connect (or perhaps two) work for him? Here is an example.
— Steve

Dear Steve,
I haven’t heard more about that Formula quick hydraulic coupler since its announcement four years ago. I’m not sure it’s still available and whether there are any problems with using it with a mineral-oil system vs. a DOT-fluid system.

There are lots of quick-disconnect couplers for automotive and agricultural applications. I know there will be a demand for them for bicycles, now that disc brakes on road bikes are becoming ubiquitous.

As another reader named Tom pointed out, TRP is developing one, but it’s not up on TRP’s site yet. TRP’s marketing director Lance Larrabee said, “Quick connect hose kits will be available before the end of the year. Price TBD. Currently our hose O.D. is 5.5mm. I believe Shimano is 5.0MM, so it wouldn’t work [on Shimano brakes].”
― Lennard

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Technical FAQ: The intricacies Di2 Synchro-Shift

Dear Lennard,
I am in the process of converting a bike from Shimano Dura-Ace 7900 to Ultegra 6870 DI2. I have the BT-DN110-1 internal battery, a EW-RS910 handlebar end junction, and the SM-BCR2 battery charger. I have used the E-Tube software to update the firmware on all of the various components and everything seems to be operating just fine. I am still waiting on a rear wheel that can carry the 11-speed cassette, so I do not actually have the bike on the road yet.

My question is, how do I make sure the synchro-shift functionality is completely disabled? I just want the bike to shift normally with no auto shifting assistance. I looked around in the E-tube software setup but I was not able to see where/how this would be done. There is quite a bit of information on the internet about how to set up synchro-shift, but there does not seem to be much info around on how to disable it, so maybe this would be something good to cover in your column.
— Steven

Dear Steven,
As I discussed in this post, there are three shift modes: M, S1, and S2 (Manual, Synchro-Shift 1, and Synchro-Shift 2). You want M mode, so all you have to do is put it in M mode. On a road bike, if you have not enabled Synchro mode, you won’t get it. You do have a battery that supports Synchro, so you can get it if you want it; to disable Synchro, you simply need to make sure that you are in M mode.

If you have the possibility of Synchro-shift enabled, you can toggle through the three modes with your mode button on your Junction A (in this case, in the end of your handlebar). You can also do this with a synched bike computer, but since you didn’t mention that you have a D-Fly Bluetooth transceiver, you will only be able to use the mode button on your handlebar-end Junction A to enable or disable Synchro modes.

When you simultaneously push both shift buttons on one lever, the LED indicator lights on Junction A will tell you what is going on. They will first tell you the battery level by only illuminating the battery LED (in the proper color to indicate your battery level). If you have the option for Synchro shift, this will be followed by both lights simultaneously glowing or flashing. If the battery LED glows green and the “+-” LED glows red, with neither of them flashing, the bike is in Manual shift mode. If these green and red LEDs flash twice, then S1 shift mode is operational, and if they flash three times, the bike is in S2 shifting mode. If on the other hand, only the battery light glows and is not followed by both lights coming on, then your bike is not currently set up to even go into Synchro mode at all, and you are simply in Manual mode.

If your bike is set up so that you could go into Synchro mode, you cycle from one of the three options to the next with two quick pushes of the mode button on Junction A. The pair of LEDs glow or flash red and green after every time you give the mode button a double push. Since you want Manual mode, if the two lights flash more than once, give the mode button another two quick pushes; do that until the red and green lights just come on briefly together and don’t flash. That indicates you’re in Manual mode, and you’ll stay there until you do another double push.

Since adjusting the system only requires holding the mode button down and not pushing it twice, there is no reason that you will go out of Manual mode in regular operation of the system; you will have effectively disabled Synchro.
― Lennard

Dear Lennard,
I have this setup and have two technical question for you:

1. In S2 mode, I would prefer that the rear cassette advance before the front chainring does. I think most riders do this naturally when in manual mode. Having the front drop from the big ring to the small ring before advancing the rear cassette is very jarring since you instantly spin out. At a minimum, this should be a configuration option. Is it? I don’t see that.
2. I have sprint shifters installed, which is also very nice when in S1 mode. It would be outstanding if they behaved as they do with the eTap system: hitting both sprint shifters could change the front derailleur. Presently, hitting both sprint shifters in S1 mode does nothing. Could this be programmed somehow? Then, S1 would essentially be eTap when sprint shifters are installed.
— Michael

Dear Michael,
While I have heard from Shimano that being able to change the S2 shift order is under consideration, there is currently no such option to change the order in which the system performs the shifts in Synchro-shift mode. Furthermore, I think you are mistaken when you say most riders shift the rear before the front on a downshift; they’re seeking an easier gear, so they drop to the inner chainring first, and then they drop the chain in back as quickly as possible to a smaller cog to reduce the sudden increase in cadence. Furthermore, if they were to go up in gear first and then drop to the front chainring, they will have bogged down and made the front shift much more difficult to accomplish, thus losing more momentum.

Shimano does not offer the option of doing eTap-type shifting in S1 mode with sprint shifters and has no intention of doing so. Why would you even want to shift in the front from the drops anyway? I suppose you could move the sprint shifters up so you can get to them from atop the lever hoods, but then you will have lost the benefit of them, namely having them right by your thumbs when you’re sprinting in the drops. Currently, as you said, if you hit both sprint buttons simultaneously, nothing happens. Makes sense; it doesn’t know what you want, so it doesn’t give you anything. On the other hand, if you were to have them set up like you want and were to accidentally push both of them while in a sprint, you would suddenly drop into the small chainring. I’ll bet you would not be happy about that.
― Lennard

Dear Lennard,
I have several Campy 10-speed record and chorus wheelsets. Are campy 11-speed cassettes compatible with the 10-speed free hubs?
— Robert

Dear Robert,
Yes they are.
― Lennard

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Technical FAQ: Heart arrhythmias, tubeless problems, and BB creaks

Cardiac tests for cyclists

Dear Lennard,
I write because, at 53 years of age, I am becoming more of a serious cyclist than I’ve ever been. I know about your experience with arrhythmia, and it occurred to me that perhaps I should do what I can to avoid a similar (or worse) fate.

Therefore, I’ve decided to seek some medical advice/testing to see if I am healthy enough to continue riding hard. I currently have no arrhythmia and there is no history of cardiac issues in my family. However, I’d love to continue cycling and challenging myself on the bike for many more years, and this would seem a prudent step.

My question to you: can you recommend specific tests beyond a basic cardiac stress test?

I was sorry to hear about your experience with arrhythmia, but I believe that your experience will help many, many others over the years. Thanks for writing about your ordeal and being public about it.
— Steve

Dear Steve,
In addition to getting a cardiac stress test (performed on a treadmill or ergometer while hooked up to an EKG machine), I recommend getting an echocardiogram done. This test can tell you the size and shape of the heart and its internal chamber sizes, its pumping capacity, and the location and extent of any tissue damage. An echocardiogram can also calculate the volume of blood each of your ventricles pumps per unit time, how much of the blood inside each ventricle gets pushed out with each contraction (ejection fraction), and how well the heart relaxes between contractions.
— Lennard

Manufacturer warning label regarding tires

Dear Lennard,
While installing new Maxxis Padrone tires onto my 2008 Fulcrum 2-way Racing 1s last week, I noticed a warning label inside the rim that stated to use only Hutchinson tubeless tires. My first two sets of tires were Hutchinsons, but then I switched to Schwalbes and ran those for a few years without incident. I contacted the folks at Fulcrum and inquired about the warning, and they reiterated that I should only use Hutchinson tires on these wheels. My hunch is that the Hutchinsons were really the only tires on the market back when these wheels were designed and tested and that they haven’t gone back and re-tested any of the new tires on the market. Thoughts?

Interestingly, I think I ran into the same situation with the Maxxis tires: the sidewall states that minimum pressure is 105psi. That seemed a bit high for a tubeless tire (and kind of defeats the purpose), so I emailed them and their response was that minimum is indeed 105, but they’ve heard of riders running them in the mid-80s without incident, but that they, of course, can’t recommend that. Seems to me that these companies have some pretty good lawyers on staff these days.
— Tom

Dear Tom,
Joshua Riddle, press manager for Fulcrum and Campagnolo, says, “Tom is right regarding the tire situation in 2008. There really wasn’t much else available, and we developed and tested with Hutchinson. Not knowing at the time how other tires that were to come to market after the launch would perform, we could only vouch for Hutchinson, as we had experience only with their tires. In 2009, we had tested plenty of other tires and the same in 2010, so the literature, warning labels, and recommendations were all amended to reflect a wider array of tubeless tires for use with Campagnolo and Fulcrum 2 way fit wheels. At the moment, you can use the tires you prefer for both Campagnolo and Fulcrum 2 Way Fit wheels.”
― Lennard

Bottom bracket knocking

Dear Lennard,
I ride a 2013 carbon Masi Evoluzione with Campy Chorus 11. For a few seasons now, the bottom bracket area has developed a knocking sound that further Internet research has helped me diagnose as a discrepancy between the bike’s bottom bracket shell’s width and the tight tolerance of the UT bottom bracket’s Hirth joint. The “Rogue Mechanic” (see below) seems to have found a cure for BBs with threaded cups (adding spacers of various width to the NDS cup until the noise disappears), but in my case, I have press-fit cups. I’ve already changed bottom brackets twice (I’m on a Praxis now) and the knocking is getting worse.

It is the Praxis “threaded press-fit” model, where one cup with the internal sleeve is press-fit into the BB shell and the other cup is threaded into the sleeve (requires two bottom bracket tools). They provide a “wavy washer” like Campy as well as a non-drive side cup, sort of a soft o-ring that’s supposed to allow for bb width discrepancies, but on the road pedaling, it’s like nothing’s changed. There’s a guy out there, “Rogue Mechanic,” who’s done some research and came up with spacers to place between the non-drive side threaded cup and the bottom bracket shell, but that requires removing the whole bottom bracket assembly a good number of times before finding the right amount of spacers and, again, I’m not on a threaded system, but on a press-fit one, so I’m not sure if removing and replacing the press-fit cup several times makes sense.

I’m so sick of this noise I don’t even want to ride. What would you suggest, short of chucking all my Campy stuff (I’ve been a loyal customer for 25 years) and moving to SRAM?
— Franck

Dear Franck,
The “Rogue Mechanic” tip is not a good option, in my opinion. I also think it has nothing to do with your creak or knock, which I believe is entirely caused by your bearings moving around within your unthreaded carbon bottom bracket shell. In fact, I don’t think that there is any need for performing the “Rogue Mechanic” tip, and you could instead damage your nice ceramic bearings by side-loading them if you do what he suggests. I also don’t think that movement in your Hirth joint where the two bottom bracket stubs meet in the center is likely to occur, as long as you have the bolt tight. That joint is very well-engineered so that the tapered teeth just keep tightening up against each other. In fact, Hirth joints have been used in automotive and aircraft crankshafts for a long time, as they can transfer high torques very well.

Yes, if you push laterally on the face of a Campy Ultra Torque crank, you can compress the wave washer and get it to move laterally. However, when actually pedaling, you will not be applying that kind of side load. I think that if you were to interview thousands of Campy UT riders, you would not find them complaining about the chainring moving back and forth and rubbing the chain from side to side on the front derailleur cage plates — at least not any more than riders on other major crank brands do (everyone gets a little side-to-side chainring movement, and that is generally due to frame flex, crank flex, spider flex, and chainring flex, not to lateral movement of the bottom bracket spindle).

I am surprised that the Praxis thread-together bottom bracket did not at least improve it somewhat. I suspect it is somehow still not tightened up against the faces of the bottom bracket shell. Perhaps those bottom bracket faces are not parallel; “facing” them might improve things.

To fix your creak, according to Campagnolo North America technical service manager Dan Large, “the only options are to Loctite or epoxy the cups into the frame. Ensure that the rider has the bearings serviced regularly and change the grease in the cups. Alternatively, the grease can be substituted with a light coat of anti-seize on the outer surface of the bearing.”
― Lennard

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Technical FAQ: Di2 Synchro Shift and Garmin connection

Dear Lennard,
I have a cervical fusion, and, in order to keep riding, I have to sit very upright on the bike and can’t tip my head forward. I can’t look back to see what gear I am on and I’m constantly cross-chaining, since I rarely know what gear I’m in. Is there any way to get around this issue? I’d also like to be able to see what gear I’m in. I ride with a Garmin, and I understand there is a way I can see what gear I’m in on it, but I’ve never seen that on any of my data fields.

I have Ultegra Di2 (I’ve ridden two seasons on it) with a compact crank, a GS long-cage rear derailleur, and an 11-36 cassette (I used to have a Lindarets Road Link, but on your suggestion, I took it off, and it still works fine with the 36T cog).
— Neal

Dear Neal,
There sure is! With Shimano Di2 Synchro Shift, you could just shift with one shifter (your right one, unless you were to reconfigure which lever controls which derailleur), and it would perform not only rear shifts, but also front shifts, when appropriate, and it would prevent cross-chaining. And, yes, you can display on your Garmin what gear you’re in, as well as your Di2 battery level and which shift mode you’re in. You would need to get a new battery and a Shimano “D-Fly” Bluetooth transceiver for Di2.

The following are some instructions for using Synchro Shift and connecting a Garmin that I wrote for the chapter on electronic shifting in the sixth edition of “Zinn & the Art of Mountain Bike Maintenance,” which will be out December 16 but can be pre-ordered now.

I am quite certain that this is the most complete set of instructions available anywhere for connecting Di2 with Bluetooth and enabling Synchro Shift. The instructions are for mountain bikes, but the only difference in this case is that road bikes do not have a digital display and instead only have an upper junction box, aka, Junction A. Even though you can hook up a digital display to your road Di2 (and you can eliminate the D-Fly if you get a Bluetooth-enabled digital display) your Garmin will display everything that the digital display would, and more clearly.

Note that S2 shifting mode is the one you want, once you get your Di2 system paired via Bluetooth. S2, or full Synchro, only requires shift inputs from one shift lever, as mountain-bike Di2 systems have offered since their inception. (S1 is Semi Synchro, where every front shift is accompanied by a double shift in the rear, and M, or manual, where the right lever only controls the rear derailleur, and the left lever only controls the front derailleur.)

In S2 mode for road, as Shimano has programmed it (which you can reconfigure in the E-Tube Project app), it will shift down from the big-front-chainring/smallest-rear-cog combination through each successively larger rear cog until it gets to the second-largest rear cog. Then, when you ask for yet another lower gear with the shift button on the right lever, it will shift to the inner chainring and will concurrently do a double-shift in the rear back to the fourth-largest rear cog. Continuing to ask for lower gears will then take through those biggest cogs until you end up on the small-chainring/largest-cog combination, your lowest gear.

When you go back the other direction and ask it for progressively higher gears, it will go to smaller and smaller cogs until it gets to a few from the smallest. Then it will shift the chain up from the inner chainring to the big chainring, and, concurrently, it will shift in the rear back two cogs larger.

Hardware required for wired and wireless connectivity

Until 2016, downloading Di2 firmware, reconfiguring shifting, or performing diagnostic checks of the system all required a wired connection to a Windows PC (and not to a Mac; those remain unsupported). Now, however, Shimano’s wireless E-Tube Project app (free on the App Store or on Google Play) for iPhones, Android phones, and tablet computers affords much of the same functionality. The smartphone app allows customizing shifting and updating firmware; the tablet app offers those functions and can also check for system errors and perform the system pre-set. Furthermore, the Di2 system can interact with many Garmin and other ANT/ANT+ cycling computers, displaying battery level and current gear combination, as well as offering switching between shifting modes.

Thing is, you must have all of the appropriate hardware to get wireless connectivity. Fortunately, other than the first two generations of road Di2, all Shimano Di2 systems are backward-compatible, so you can upgrade some items to get this functionality while still using your existing shifters and derailleurs. Furthermore, all XT Di2 components are interchangeable with XTR Di2 ones.

To enable Bluetooth and ANT+ compatibility, the battery must be either the BT-DN110 (cylindrical, for installation inside of a seatpost, steering tube, or Shimano battery case — or the BT-DN100 original-shape external battery; the older versions of these batteries (SM-BTR2 and SM-BTR1) have insufficient memory for Bluetooth connectivity. You also need a transceiver in the system; this can be either a digital display with a Bluetooth chip, namely the XTR SC-M9051 (not the SC-M9050) or the XT SC-MT800, or a “D-Fly” inline unit — either the EW-WU101 (both ports on the same end) or the EW-WU111 (one port on either end). With a D-Fly inline transceiver, you also need an additional short e-tube wire.

If you want to update, check, or reconfigure your Di2 system and don’t want the expense or trouble of obtaining wireless connectivity, you can download the E-Tube Project software from and plug a Windows computer into your bike’s Di2 system with Shimano’s SM-PCE1 PC interface device and accompanying USB cable. It plugs right into the charging port on Junction A or on the digital display. You can then update firmware, diagnose and correct problems in the system, and customize shifting options on your computer screen. Without the interface device, you can still do firmware updates using the E-Tube Project software by plugging into your Junction A charger port with your USB charger connected to a Windows PC.

ANT+ connection with a cycling computer

What’s possible in communication between cycling computers and Di2 is rapidly changing. As of 2017, there are two levels of compatibility with Di2: either just displaying battery level and current gear combination on the computer, or displaying Synchronized Shift setting (in addition to battery percentage and gearing).

The instructions below apply to connecting popular Garmin computers to Di2; other Di2-enabled ANT+ computers have similar features. Garmin models going back a few years and at many price points, like the Edge 510, 810, 520, 820, and 1000, the Forerunner 735, 920, and 935, and the Fenix 5, can all display Di2 shifting status and battery percentage. Garmins that also support Shimano’s Di2 Synchronized Shift capability are limited as of this writing to the more recent Edge 520, 820, and 1000 models. Note that Di2 connectivity is not supported on older Garmin models without updated Garmin firmware.

Setting up Di2 display on Garmin:
1. Select the icon of a crossed wrench and screwdriver on the home screen. The settings menu will appear. On some (older) models, you can also access settings from any training page by touching the screen; an overlay will come up with the settings icon, as well as the home, left and right scroll, navigation search, and wireless connection icons on it To select a Garmin icon, touch it on the screen.

2. Go to the ANT+ sensor list from the settings menu. Depending on computer model, either select: (a) “Bike Profiles” and select a bike stored in memory, or (b) select “Sensors.” Alternatively, on some (older) models, if you brought up the overlay on a training page instead of initially going to the home screen, get to the “Bike Sensors” list by selecting the wireless-connection icon (it looks like a dot broadcasting to the left and right). On some (newer) models, you can directly access the sensor list from any page by pulling down with your finger from the top of the screen; it pulls down a curtain with backlight and connection options; select “Connecting to Sensors.”

3. Select “Di2” on the sensors list. If “Di2” is not one of the icons displayed, then your Garmin firmware is too old. Download “Garmin Express” online and create a login; from there, update your firmware. With updated Garmin firmware, return to step 1.

4. Select “Enable” on the “Shimano Di2” screen.

5. Select “Search” or “Connect.” Once connected, it will display, “Shimano Di2 found.” In order that the Garmin can find your Di2 system, unplug and re-plug in both wires to the D-Fly transceiver or all three wires to the digital display. If it doesn’t connect, push the mode button for about a second on your digital Di2 handlebar display until a flashing “c” appears, or Junction A until the two LEDs flash red and green. If the “c” doesn’t appear on your SC-M9051 or SC-MT800 digital display (i.e., if it passes on to adjustment mode or post-crash re-coupling mode), you must first update your SC-M9051’s or SC-MT800’s firmware with a wired connection to a PC (many of these units were shipped with the Bluetooth chip but without the firmware to make it work). If it still doesn’t find Di2, restart the Garmin and try pairing it again. Once the Garmin is paired with Di2, continue with step 6 to create a screen on which to view the Di2 functions while riding.

6. Select the settings icon. It’s the wrench/screwdriver icon. Again, find it by: a) returning to the home page, or, b) pulling up the overlay on a training page.

7. Select “Activity Profiles.”

8. Select one of the profiles.

9. Select “Training Pages” or “Data Screens.”

10. Select a page that is currently shown as “Off.”

11. Select “Enable” or “Enabled.” This turns the page on.

12. Increase, decrease, or maintain the number of fields on the page. Select “+” or “-” to change the number of fields, then select the check mark in the lower right corner. To leave the number of fields unchanged, simply touch the check mark.

13. Change fields to display Di2 information. Touch any field to open the “Select a (Data Field) Category” page, scroll (using the arrows) to “Gears” and select it; this will bring up options like “Di2 Battery Level,” “Front Gear,” “Gear Ratio,” “Gears,” and “Rear Gear,” and, with newer models, “Di2 Shift Mode,” “Gear Battery,” and “Gear Combo” will also appear. Fill as many fields as you want with Di2 fields. I recommend having at least two fields, namely “Gears,” which shows graphically which front and rear gears the chain is on, and one displaying battery percentage. With newer Garmins, also create a “Di2 Shift Mode” field to show whether you are in M (Manual), S1 or S2 (pre-programmed Synchro Shift modes), or in a custom Synchro Shift mode (which you create with your smartphone or tablet in the E-Tube Project app or on a Windows PC connected via the SM-PCE1 interface device).

14. Select the check mark at the bottom of the Garmin screen. You’re done. You now have a screen you can loop to when riding that shows what’s going on with your Di2 system. If (when) your Garmin doesn’t find your Di2 system when you turn it on to head out for a ride, you will have to go through steps 1-5 to pair them.

Using the E-Tube Project wireless app

As with ANT+ cycling computers, you’ll need either a Bluetooth-enabled digital display, or a D-Fly inline unit (either an EW-WU101 or EW-WU111) wired into your system.

1. Download E-Tube Project and open it. Find it for smartphones and tablets on iTunes or Google Play.

2. Select the Bluetooth LE connection box and push the Di2 mode button on the bike’s digital display or Junction A. Push the mode button for perhaps a second — not long enough to bring up adjustment mode. A flashing “c” should appear on your digital Di2 handlebar display, or the two LEDs on Junction A will alternate flashing green and red. If the “c” doesn’t appear on your SC-M9051 or SC-MT800 digital display (i.e., if it passes on to adjustment mode — see 6-8 — or post-crash re-coupling mode — see 6-9c), you must first update your SC-M9051’s or SC-MT800’s firmware with a wired connection to a PC (many of these units were shipped with the Bluetooth chip but without the firmware to make it work). Once the connection is made, a box with the part number of your Di2 transceiver will pop up on the phone or tablet screen; select it.

3. Update the firmware of your Di2 transceiver. This will start automatically. During the process, it will ask you to change the default “000000” ID code of your Di2 transceiver; go ahead and do this. It requests “half-width alphanumeric characters,” whatever those are; just pick another 6-digit number. At some point, the firmware update will stop before it’s complete and will give you an error message. Don’t worry; it’s not you. It’s also possible that you will be able to connect this time, and you won’t get the error message until you try to connect the next time. In that case, you won’t have to do the following step until you log onto the app next time. BTW, the tutorial on the app is not a video, with the short green bar showing how far it has (not) loaded; rather scroll to the right to view it page by page.

4. Delete your Di2 transceiver on your tablet or smartphone. Yes, really. If you don’t do this, the app will try to connect to your Di2 transceiver with the old, “000000” password and will display a spinning wheel of death without connecting. So, select “Bluetooth” in your phone or tablet settings menu. Your Di2 transceiver’s part number should appear on the list of your devices; click on its information box and select “Forget This Device.”

5. Select the Bluetooth LE connection box in the app. It will display a box with the part number of your Di2 transceiver; select that for the app to connect to. Now you should be connected again, with your new password.

6. Update firmware for all components. Ones that are up to date will be grayed out and will say “latest.”

7. Play as you wish. Now you can customize which shift buttons do what and which Synchro Shift protocols you can toggle between and how and at what points the derailleurs perform double shifts.

8. Disconnect the app. This is THE MOST IMPORTANT STEP, and it’s not obvious in the app. Click on the little three bars in the upper right of the phone screen to bring up the main menu, and select “Bluetooth Disconnected.” Right? It should say, “Disconnect Bluetooth” or words to that effect, but it doesn’t. This will disconnect your phone or tablet and save whatever changes you have made during your session.  But if you don’t do this, your Di2 components will continue to either be connected or to continue trying to connect to your phone or tablet. The symptom will be that the derailleurs will not respond to the shift buttons, and the charger will flash a fault light when plugged in; meanwhile, the Di2 battery will drain rapidly (the Bluetooth LE connection draws a lot of power), while not being able to be charged.

NOTE: A similar possibility for neglecting the most important step (saving changes and disconnecting) exists with the wired PC connection to E-Tube Project. In the main menu, the last rectangular option box was always “Complete Setup” in years past. But now with the advent of the wireless connectivity, an additional “Bluetooth LE” option box has appeared in the column; this has pushed the “Complete Setup” box to the next page, and you have to know to scroll to it. Now you know.

On a system without a digital display, once the firmware is updated so that the bike’s Di2 system is fully Bluetooth-enabled, it is Synchro-Shift enabled as well. Junction A not only controls which shifting mode the bike is in (with double-clicks of the mode button), but it also now displays it.

When you hold down a shift button (or a pair of them) to display the battery charge status, the battery LED first shows the battery status (see 6-1c), and then both LEDs show the shifting mode. If the battery LED glows green and the “+-” LED glows red, with neither of them flashing, the bike is in Manual shift mode. Two blinks of these green and red LEDs means S1 shift mode is operational, and 3 green/red blinks means the bike is in S2 shifting mode.

A paired ANT+ cycling computer that is recent enough to support Synchro Shift will also display the shift mode. And, in the phone/tablet app or in the wired PC software, you can put custom shifting patterns of your design into those S1 and S2 slots.

I hope you’re able to get this all set up. You would then not only be able to see what gear you’re in while you’re riding, but, as long as you only shift with the one shifter, you would avoid cross chaining, even without the Garmin on your bike to see what gear you’re in. All you do is simply ask it for an easier gear or a harder gear by pushing the downshift or upshift button on your right lever; it will do the rest.
― Lennard

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Technical FAQ: Do bigger shoes make for faster riders?

Dear Lennard,
I can’t help but notice that some of the taller riders, Chris Froome among them, seem to have unusually big/long feet and shoes. This is not limited to Froome or even riders tall in stature, and it appears to be disproportional. My question is, from a biomechanics and physics standpoint, does this offer riders greater leverage and power with the increased length? If so, would this encourage riders to wear larger shoes than they would off of the bike, given the improvements in stiffness and weight of carbon soles. Finally, should the UCI regulate shoe size “fudging?” (I know that last question might raise the ire of some readers.) Again, I am not signaling out Chris Froome; to me the phenomenon across the peloton raised the question in my head.
— Joe

Dear Joe,
I don’t think there is a way in the world that it could be an advantage to ride with a longer shoe than your foot size would demand.

First off, I think that controlling a longer lever (i.e., from the heel to the pedal cleat) with the calf muscles is mostly wasted energy. The power to propel a bicycle primarily comes from the quads, glutes, and hamstrings. Developing those muscles makes sense. However, developing bigger calf muscles in order to flip a longer shoe downward would result in a net loss in speed, in my opinion, by adding more weight to the lower leg (which moves faster, in a bigger circle, than the upper-leg muscles), thus costing energy with minimal propulsion gains.

Also, the longer the shoe, the higher the saddle has to be to get the same knee and hip angles at the bottom of the stroke; the longer shoe makes the effective leg length longer. A higher saddle results in more aerodynamic drag and a higher center of mass, resulting in more power required to maintain the same speed and reduced cornering and bike-handling effectiveness.

Most of the custom bikes I build are for extremely tall riders. As you might imagine, they generally have big feet. I try to create the opposite setup with them from the one you are proposing. Based on my personal experience as a tall rider with big feet, I always recommend that riders with big feet push their cleats back on the shoes as far as they can.

Mountain-bike shoes allow the cleats to go farther back than do most road shoes. On MTB shoes, this means using the further back pair of threaded holes in the shoe plate and sliding the plate back as far as it will go in the two sole slots.

On road shoes, there is only so much you can do, unless your shoes have slots on the three mounting holes. In my case, I use Speedplay Zero pedals with the “Cleat Extender Base Plate Kit” under my cleats. I slide the extender plates back as far as I can on the shoe, and then I mount the cleats using the rearward set of holes. This results in my cleats being 14mm further back than the furthest I could get them back without the plates.

The far-back cleat allows me to run a lower saddle, thus getting lower to reduce wind drag and improving handling. Having the cleat so far back also greatly reduces “hot foot” pain under the metatarsals; this is how I take advantage of the rigidity of modern carbon shoe soles — distributing the pressure of pedaling over the entire foot, rather than concentrating it under the ball of the foot. I also have a painful condition (developed from years of cycling and cross-country skiing?) called “Morton’s neuroma” between my metatarsals, and the far-back cleat is part of the solution that allows me to ride pain-free.

I think it is merely coincidental that Chris Froome happens to have big feet (and hence big shoes) and wins the Tour and Vuelta. Rather than being an advantage he capitalizes on, it may be something he overcomes. I think the UCI should not devote any resources into catching “shoe fudging” and instead direct more resources into its testing for hidden motors.
― Lennard

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