ENVE the Mandem

With the recent availability of my ENVE 29XCs, the Mandem has received an upgrade.




As expected, they’re snappy, durable, incredibly fast, and awesome looking. These are 32/32 laced to DT240 hubs. I’ll give a durability update in a few months…

As related in my last post, the ENVEs weigh 780/852 grams front and rear, versus 966/1236 grams for the generic aluminum wheels that were previously on the Mandem.




That’s a reduction of 570 grams of rotating mass–1 and 1/4 pounds. A reduction in rotating mass, going to a wheel that is wider, more aerodynamic and stronger. Win, win, win.

I look forward to a lot of miles on the Mandem.  I also look forward to one final upgrade.  Stay tuned.


Zipp Firecrest 202 Tubeless Setup

(Brief intro: those who follow this blog know of the Mandem.  It’s an amazing bike, but was built up with the wheels that we had available at the time.  Of late, I had an opportunity to pick up a set of Zipp Firecrest 202s, set up for disc brakes.  They’re amazing wheels, but do not have a weight rating to support the Mandem with 2 riders.  Accordingly, my plan was to move my set of ENVE 29XC wheels from the Moots to the Mandem, and put the Zipps on the Moots.  But in order to do so happily, I wanted to run the Zipps tubeless.)

Zipp 202s are supposed to be amazing wheels.  Light, aero, durable, disc-compatible…all good things.  But they’re not tubeless compatible–or they’re not supposed to be.  I wanted to run a set, but I wanted to run them tubeless.  They’re going on the Moots (linked above), which is an all-purpose, all-terrain, gravel, mixed-surface, crappy-pavement, whatever you throw at it bike.  I wanted 202s because they’re light, surprisingly aero (according to tests) and because the narrow depth is supposed to be cross-wind resistant.  I’ve had conditions on gravel roads in DeKalb where the cross-wind is so strong that I have a hard time keeping a straight-ish line on loose surfaces…so I need all the help I can get.

Jumping to the lead: Zipp Firecrest 202s can be set up tubeless.  I am not responsible for your warranty claims.

The setup was pretty simple.  I took some Stan’s 25mm tubeless setup tape and used 2 wraps around the wheels.  2 wraps covered the inside of the rim, almost from bead to bead.  I then mounted up some tires with tubes, inflated them, and let the whole setup sit overnight with 80 psi in it.



After 24 hours, I pulled the tires and tubes off, and the tape was nice and firmly adhered, like so:


You can see that it does a really nice job of going up to the bead, without impinging on the bead.



For comparison’s sake, I did a little weigh-off between the ENVEs and the Zipps. The Zipps are stock build–the “77/177D” hub, which is convertible from QR to 2 different thru-axle specs, Sapim brass nipples, and 24/24 Sapim CX Ray spokes. The ENVEs feature DT Swiss 240 hubs (also convertible), ENVE nipples, and 32/32 CX Ray spokes–so a heavier build. Both wheels (front and rear) are weighed with just the built wheel, plus tubeless tape (ENVE tape on the ENVEs, Stan’s tape on the Zipps). No rotors, no cassette, no valve stem.



ENVE front weighed out at 780 grams.



ZIPP front weighed out at 734–a little under 50 grams lighter. Since the spokes each weigh 4.5 grams, plus something for the nipples, I’d guess that all of the weight difference is just in the extra spokes on the ENVEs.


Just for fun, the fully built, taped, stem’d, tire’d and sealant’d Zipp front comes in at 1414 grams (with 2.5 ounces of sealant).



The rear ENVE comes in at 852 grams…


Versus 840 grams for the Zipp.



Accounting for the spoke difference, my guess is that the rear DT240 is lighter than the Zipp hub. Both hubs are set up for 11 speed. (And of note, the Zipps were perfectly clean, and the ENVEs had a couple grams of dried sealant on the inside). I was pretty surprised by how close the weights were.

Those weights include 2 wraps of Stan’s tape on the Zipps, versus one wrap of ENVE tape on the ENVEs.  The ENVE tape is more like Gorilla tape, and I like it better.

Here’s the finished product:


Tubeless setup was a breeze. Slapped the tire on, removed the valve core, and one hit with the compressor–the tire instantly seated. I let the air out, put some Stan’s in, put the valve core back in, and pumped them up to 60 psi. The Stan’s shake and roll ensued, and everything sealed tight as a drum. 48 hours later, almost no pressure loss.

I don’t have enough time on the Zipps to comment on their durability. I have a lot of confidence in the ENVEs, based on the abuse I’ve given them on gravel and on the Fuel.  I’m hopeful that the Zipps serve just as well.  One feature I really do like about the Zipps is the external nipples.  While the ENVEs have not needed attention in terms of truing, if they ever do, it will require stripping the tire off, pulling off the tubeless tape, and getting at the internal nipples.  The Zipps are a far simpler enterprise.

In early riding, the Zipps are…well, Zippy.  They roll just as fast, if not faster, than the ENVEs.  They seem a bit snappier under acceleration, but I don’t think they’re quite as rigid.  From what I’ve read, they’re intended to have some more vertical compliance for better riding on hard surfaces.  That may be what I’m feeling.  Nothing weird (they go where they’re pointed), but noticeably different from the ENVEs.

As far as aero goes, I’m trying to decide if it’s in my head or not…but they seem more aerodynamic.  Crosswinds are less noticeable, headwinds are more bearable.  That’s all subjective, but subjective is important when you’re the rider.

In terms of tubeless setup, I didn’t encounter any roadblock that made me second-guess proceeding forward.  The Zipps have a nice bead that made setup easy, and the tape worked like a charm.  I hope to get a lot of life out of them.

Can I Run Hydraulic Brakes on my fatbike in Winter?

(Editorial note: In addition to writing this blog, I’m the SuperMod of the Fat Bikes page on Facebook, which currently has over 10,000 members.  From time to time, the page gets repeated questions from members, and accordingly, we are developing a Fatbike FAQ page to answer those questions.  I’ll be hosting that here.  Helpful Fatbike related topics will be posted on here, and linked to a master link of the FAQs.  This is the first of those posts).

Many entry-level fat bikes come with mechanical disc brakes.  One of the very first questions that gets commonly asked by those new to winter biking is whether they can use hydraulic brakes on their fatbike, in winter.

The answer: Yes.

Have a nice day.


Ok, just kidding.  We’ll give some more content.

Why run mechanical disc brakes in winter?  When perfectly adjusted, they have good braking power, and you don’t have to worry about hydraulic fluid–so say the proponents.  Why not to run them?  There’s a myriad of reasons:

  1.  If not perfectly adjusted, they don’t have good braking power.  In winter, when the pads will likely have water/crud/ice on them, that can majorly detract from braking power.
  2. If they get wet and then freeze, the mechanical components do not work well, and they can either freeze up (no brakes) or freeze tight (no movement).  Both are bad.
  3. Over time, when exposed to salt, snow, slush, etc., the mechanical components rust/seize/wear badly.  In my experience, unless you’re really on top of it, you can ruin a set of mechanical calipers in a single season.
  4. With a really good set of cables/housing, the cables should be fine.  But with a cheap set, you’re in trouble, as the cables will bind when it is cold out, and then you’ll be back to #2 (no brakes or seized brakes).  Also, even with a good set of housings, mishaps can take your brakes out.  For example, last winter I was riding a frozen river and broke through.  The right side of my handlebar was dunked in the water.  Water got into the housing, froze during the ride, expanded, and split the housing.  I lost shifting, because it took out my rear derailleur housing.  Because I used hydro brakes, my brakes were fine.  With mechanical brakes, I would have lost brakes and shifting.
  5. Generally speaking, mechanical brakes require more attention in inclement conditions than do hydro brakes.  (IMO, mechanical brakes are always more work…but that’s because I like my brakes to function perfectly, and with mechanicals, you’re always chasing the right tuning).

So what about hydro brakes?  Can they be run in the cold?  Absolutely.  In my experience, over several years of fat biking in the winter, hydro brakes are far more reliable, resilient and durable.  They’re better suited to winter than mechanicals.  They are sealed, and can withstand being dunked, frozen, and ridden further.  From time to time, if you get them really wet, they may ice up.  The solution is to pedal a bit and hold the brakes down lightly…they’ll self-clean and clear off the ice.  Set them up once, and go.

Whenever this topic comes up, the inevitable question is: Shimano or SRAM?  The answer: whichever you prefer.  I’ve run AVID and Shimano brakes.  I prefer Shimano, because they function more reliably, are easier to bleed, and frankly, require less attention.  After initial setup, I’ve never had to bleed my Shimanos…across a number of bikes (both drop bar and flat bar hydros).  With Avids, a lot more attention was required.  For example, my Beargrease originally came with Avid XX brakes.


I replaced those with Shimano XTRs, because of recurrent air/bleeding issues.


The next thing you will hear is: “Avids use DOT brake oil and Shimanos use mineral oil.  Mineral oil freezes at a warmer temperature than DOT oil, so you should use Avids so that the oil doesn’t freeze up when riding.”  While it is true that mineral oil has a higher freezing point than does DOT brake fluid, this point is irrelevant in all but the worst conceivable conditions.  I’ve run my Shimanos in temperatures below -35F.  (Quick note: that’s actual temperature, not windchill.  Windchill is the perceived temperature on exposed skin, based on wind and temp; it is irrelevant to mechanical things such as brakes, which do not perceive temperature.  So when talking about mechanical items, stick with actual temp, not windchill).  Even at -35, I had no issues with the brakes being sticky, sluggish or frozen.  That was the case, even after several hours of outdoor biking, when everything was fully acclimated to the cold and fully as cold as it was outside.  That was the case after hauling my bike on an exterior bike rack in those conditions, and then riding it.  That was the case even after being set in the snow on a break, and then picked back up and ridden.  From my perspective, the greater resilience of Shimanos (and lessened need for bleeding) means that they are less likely to have contaminants enter the brake system…and I’d be more worried about the contaminants freezing than the fluid freezing.  Of note, I haven’t run the latest generation of Avid brakes, which I understand are greatly improved.  But unless you’re regularly riding in temps much colder than -35, I’d suggest you pick whichever hydro brakes you prefer and run them, without worrying about mineral vs. DOT brake fluid.

So, in short: If you want to run hydro brakes, they’ll work in the cold, and they’ll almost certainly work better than mechanical brakes.  The fluid won’t freeze up–unless you’re riding in really extreme conditions.  My personal experience extends to -35F, and I’ve read of others using them successfully down to -50F.  Buy a set you like, set them up properly once, and go for it!

Derailleur Hanger: The Move to a Circuit Breaker

Have you ever broken  a derailleur hanger?  I mean really, really broken one?  I mean broken one so hard that the derailleur goes into your rear wheel, breaking a bunch of spokes and taking you out of a 200 mile gravel endurance race?  No?

Me neither.  Who would do something like that?

But some people have.  Some very nice people.  And those people started thinking about how dumb derailleur hangers are.

You see, years ago, cars included these things called fusible links.  I had a mid-70s Jeep CJ and it was full of them.  I spent untold hours hacking them out of the wiring harness.

In the world of wiring, you have to accept that from time to time, something will draw too much current.  When it draws too much current, it can result in the wiring harness getting hot and/or burning up–literally melting and/or catching fire.  For a variety of reasons, that’s not a good thing.  And hence, cars include circuit protection.  The basic idea of circuit protection is providing a weak link in each wiring circuit–something that will ‘give’ in the event of an overdraw in the circuit, before the wiring harness (or an electrical component) blows up or catches fire.  That’s a very good thing.

Circuit protection in cars comes in three typical forms.  There are fusible links, which are essentially a failure point built into a length of wire, directly wired into the wiring harness.  The fusible link will burn up before the rest of the harness, but once it goes, replacing it involves hacking and splicing a new fusible link into the harness.  The second type of circuit protection is a fuse.  A fuse is a little circuit protector that goes in a fuse holder or fusebox and serves the same purpose; it blows before the wiring harness burns up.  When a fuse blows, you can pull the fuse out and just stick a new one into the fuse holder (assuming you fixed the underlying issue).  No drama, no hacking, no wiring.  Much more eloquent.

The third general type of circuit protection in cars is a circuit breaker.  A circuit breaker is an automatic device; it will trip when there’s an overload, and once the overload condition goes away, it will reset.  The power windows in your car are likely wired to a circuit breaker (unless they’re on a computer-controlled circuit).  If you hold the ‘window up’ button for too long, the motor will start to heat up and the circuit breaker will interrupt the circuit, allowing the motor to cool down.  Thereafter, it automatically resets.  (Sure, there are manual-reset circuit breakers, but let’s get back to bikes here, some time).

The general thought I have is that in most applications, a circuit breaker is superior to a fusible link.  It doesn’t require tools to fix, and can be reused and reset.  You want the protection that it offers, but when it trips, it’s a lot easier to deal with a circuit breaker (or for that matter, a blown fuse) than it is to deal with a burned out fusible link.  And that brings us back to bikes.

Derailleur hangers are fusible links.  They’re designed to be a weak spot in the system–a spot that will break before the derailleur explodes (hopefully).  But when they break, they break.  You have to have a spare with you, unbolt the old one, bolt a new one in.  Not simple.  Not eloquent.  Necessary, but inconvenient.  And when they do break, the derailleur is fully cut-loose, ready to wreak havoc on unsuspecting rear wheels.  That leads to my underlying suggestion: derailleur hangers need to become more like circuit breakers.

Imagine a derailleur hanger that, instead of being firmly bolted on, was held on by high-powered magnet and perhaps a pinch-bolt.  Under normal conditions, it would be totally rigid.  Under ‘something’s about to break’ conditions, the power of the magnet and friction of the pinch bolt would be overcome, and the derailleur would pop off the frame, serving the purpose of derailleur circuit protection…but after you stopped, you’d be able to loosen the pinch bolt, pop the hanger/derailleur back on, tighten the pinch bolt, and pedal off.  No need for extra parts, no heartache.

The one missing piece of that setup is something to prevent the derailleur from blowing into the rear wheel and taking it out.  I’m still working on that part…but I’m picturing either a limiting cable that would attach the derailleur to the frame and prevent it from moving laterally into the wheel, or a tension device of some form (spring?  elastic?) that would pull the derailleur and hanger away from the wheel and out towards the chainstay, in the event that the hanger released from the frame.

Is this needed on every bike?  Certainly not.  There’s a narrow niche market of bikes that could use this technology.  Fat bikes, gravel bikes, mountain bikes…there are some potential applications.  There are certainly other solutions as well..singlespeed, internal geared hubs, carrying a spare derailleur hanger, etc.  But the current system seems to inelegant.  This–this seems like a more intelligent approach.

I may be an embittered veteran who suffered a broken hanger.  Ok, I am that person.  But regardless, there’s still room for improvement in the design of bikes.

Bontrager XR3 Review

My Fuel EX 9.9 was ordered with Bontrager XR3 tires, and I’ve used them for a year, and a year’s worth of mileage.

Over the weekend, I replaced them with a set of Continental Trail King 2.2s.

This post represents my thoughts on the XR3s, and the reason for the change.

First, I ran my XR3s on ENVE XC rims, taped with ENVE tape, tubeless.  As far as tubeless goes, these tires set up the easiest of any tires I’ve ever used.  For reference, Chad threw a pair of XR3s on a tubeless wheelset and just pumped them up–leaving them in the shop for a few weeks–and they held air perfectly.  The tires are just fantastic at tubeless.  For my purposes, I was running 2.2″ tires, and used 2 ounces of sealant per tire.  Over the course of the year I ran them, I cleaned them out one time and replaced the sealant.  I never had any issues with them–even if I went a month or two without riding the Fuel, they’d hold air amazingly well.

The tread pattern on the XR3s is good for midwestern conditions.  Good, aggressive knobs, but close enough together that they roll pretty smoothly on hard surfaces.

The knobs on the edge of the tread get knobbier, for better grip when yanking and banking.

I tend to use the Stan’s formula for determining starting pressure with mountain tires.  In short, rider weight divided by 7 = x.  X -1 = starting front pressure, x+2 = starting rear pressure.  For me, that suggests around 23 up front and 26 in the rear.  After some time on the bike, I tended to set them around 24-25psi front and rear, with good results.

Over the course of a year, they saw varied terrain in several states, and also some gravel and some pavement.  While they were not fond of wet leaves (what is?), they acquitted themselves admirably in most conditions.  They really did not like sand, but that may be more a reflection of my riding ability than their traction.  They self-cleaned surprisingly well in mud, were great on hardpack, did well on loose over hard, and most other conditions.  In most conditions, they would slide progressively and let you know when you were exceeding available grip.  To a point.

The “to a point” is a critical note.  I’ve tried to up my game with mountain biking–increasing my speed, braking less, having more confidence, riding harder lines.  It’s hit or miss, in all fairness, as my skill still needs a lot of improvement.  My concern about the XR3s is that they have a finite breaking point where your cornering speed exceeds available traction, and at that point, you’re gone.  They go from gradual, controlled drift to low-side, sliding on your leg and wondering what happened, instantly.  Before these, I spent a lot of time on Maxxis Ikons–which had less ultimate grip, but which were more recoverable.  If they cut loose and slid, you could reestablish traction and carry through a corner.  The XR3s have more grip, but once they go, they’re gone–and in a snap.  I don’t know how much of that to attribute to the tires, and how much to my skill or absence thereof, but I’ve low-sided enough times with these–and in a snappy, instant fashion, for it to be observable and disconcerting.

The XR3s were not fast-wearing; they still show a lot of good tread on them.  The reason that I’m swapping them out is because of a flat I had on the Chubb trail.  I was climbing an obstacle and heard that disheartening hiss of air leaving the tire.  I stopped, rotated the hole down, and tried to get the Stans to seal…a little blast of CO2 and a second try…no dice.  On the trail, we tubed it quickly and continued on.  Back home, I dug in for the post-mortem.

I don’t know what caused the hole (rocky trail with 12-18″ rock lips that we were climbing up), but it is a neat, round hole.  There is a chunk of rubber about 2-3mm across that is just missing (perfect circle), and around that, an area about the size of a pea that is deformed.  The weird part is that on the inside of the tire, the casing in the area of the hole was delaminating–whatever punched the (relatively small) hole also cut the tire casing at the (relatively small) hole, and the fabric inside the tire started pulling apart around the hole.  I was hoping to boot the tire and continue tubeless, but that’s a non-starter.

I threw on the Trail Kings for a few reasons.  First, in full disclosure, I had them sitting on the shelf from my old El Mariachi.  Second, I loved them on that bike, and have wanted to try them on the Fuel for some time, as the side knobs on them are super-gnarls, and I remember them being very predictable (even on a rigid SS bike).  Third, I remembered that they set up super easy tubeless, and held air well–and never let me down with a flat on the ElMar, even rigid, with my ‘not so delicate’ riding style.

When I ordered the Fuel, you had to pick a Bontrager tire (obvs).  Out of the available options, the XR3 was the clear choice, and I enjoyed my time with it.  Generally speaking, a good tire for many conditions.  I chose not to replace just the (failing) front with another XR3, as I wanted to see if I could cure the snap low-siding I’ve experienced with a different tire, and I’m hoping the Trail Kings will solve that problem.  Again, my complaint isn’t that the XR3s ran out of traction, but rather the fashion in which they did–snapping from a controlled skid into complete loss of traction low-siding.



Reverb Dropper Post Update

The last update I did on the Trek Fuel EX 9.9 indicated that I really didn’t use the dropper post much.  That was then.  This is now.

Now, I can’t imagine riding without it.  It’s truly a game-changer.

Extend it to full height and pedal, climb, cruise with maximum efficiency.  But when the trail turns technical or heads downhill, drop the saddle a few inches and confidence soars.  Your center of gravity lowers, your ability to move in front of or behind the saddle–to move anywhere on the bike–is greatly increased.  It’s a whole different ballgame.

I wasn’t really using the dropper until a friend of mine explained the significant advantages.  I figured what the heck–and gave it a shot.  I’m glad I listened.  It makes a HUGE difference in your ability to control the bike, and in your confidence going quickly through difficult terrain.  I LOVE the ability to go up and down with the handlebar-mounted control. Increasing confidence means increasing speed, which means pedaling less, which means going further, faster, with less effort.  Win, win, win.


Well…a year in, my Reverb has about a 1/4″ at the top of the travel where it feels soft.  It goes all the way up, but when you sit, it settles just a smidge.  I need to spend some quality time with it and try to figure that out.

My other criticism is really more of a wishlist.  I wish it had 2 positions: fully extended, and a ‘down’ position.  In a perfect world, you could hit a button and have it drop to the drop setting (without having to weight it), then hit it again and have it fully extend.  That would be a very complicated system, and isn’t likely to happen anytime soon…but it would be magical.  I think I’d prefer to have  a shorter travel dropper, so you could drop through all the travel and hit your ‘down’ position quickly.  As it is, when I’m dropping, I sometimes overshoot and then end up with the saddle too low…and then you’re either riding super-low, or trying to raise it up a smidge while cruising hard terrain.

In any event…at one time I was talking about just putting a standard post on the bike.  I’m incredibly glad I didn’t.  The dropper post makes a huge difference, and I highly recommend it.  If I was getting one, I’d look at the Thomson one, and I’d look to see what Crank Brothers is coming out with.  Ideally, it would be cable controlled, rather than hydraulic…as I suspect that my soft spot is a hydro issue.  There will probably be an upgrade in my future, at some point.