Technological Confluence

So what’s this thing all about?

I’ve been thinking about a new road bike for several months. I *loved* my Tarmac, but there are lots of things going on in the road bike space, and I’d like to have more first-hand experience with some of them. What things?

Di2 has been around nearly a decade, but I’ve never had a Di2 bike. I’ve thought about it, but it just never quite launched. Customers who have Di2 cannot rave enough, and I’ve wondered if I was missing out.

Road disc is happening for good reason. It’s super consistent in all weather. The modulation is superb. The amount of hand strength required is very low. Generally speaking, disc bikes allow for greater tire clearance, and bigger tires are another trend.

Lastly, aluminum road has been making a comeback. A decade ago, it was not at all unheard of to purchase a bike with an aluminum frame, a carbon fork and an Ultegra drivetrain. Then one day — poof! — that bike was largely unavailable. You had to get a carbon (or somewhat boutique) frame to get Ultegra-ish (Ultegra, Rival, Force, etc.) components.

I built this bike from a frame and a bunch of parts, many new, some old. It had been my intention to purchase an off the rack bike, but I stumbled upon a hydraulic Di2 kit and couldn’t say no. Such is the way bike budgets are shattered.

This is a Specialized Allez Sprint Disc frame. Why? Why not. It matched up really closely to my Tarmac when I looked at the geometry charts. The Allez Sprint does not have a reputation for being noodly and over-compliant, but I rarely ride my road bike more than 40 miles. I went into this expecting a pretty stiff bike. More on that soon. Also: the Allez Sprint is not the only aluminum road frame on the market. It’t just the one I picked.

I’m gonna flip into old man mode here for just a minute and wonder why anyone thinks we should run hydraulic hoses inside the frame. And fork. Talk about a lot of work for limited gain. And Di2 is not appreciably, if at all, easier to run through a frame than cables. Suffice it to say that the build was more time-consuming than I expected. In the end, despite my whining, I confess that it does have a sleek look now that it’s all together. Thus is this circular discussion complete.

Here we have a hydraulic brake line run through a fork leg (for no good reason! (smiley face)) to a flat mount brake caliper. I’ve been whining and moaning about this flat mount stuff since it appeared on the market, and my experience trying to get this stuff not to rub did nothing to improve my feelings.

I’m gonna veer off on a heckuva tangent here. This bike has a Shimano hydraulic brake system. Look at that thing: fins on the pads and some kinda crazy rotor that looks like part of a fancy turbine. All of this technology exists to keep the rotor cool. Shimano has three types of rotors. One is pain stainless, and it works great. The second type of rotor employs ICE technology, which means that it has an aluminum heat sink sandwiched between two pieces of stainless. This type of rotor runs quite a bit cooler than plain stainless. The third type of rotor is Freeza, which has ICE technology plus more aluminum hanging in the wind and runs cooler still. This is the type of rotor pictured above.

So what’s the deal with all of this? Why is cooling such a big deal, and why don’t other brands have all of these interesting technological options? Well, we start with the fact that Shimano hydraulic systems use mineral oil as the hydraulic fluid. Mineral oil is lighter than water, so if water gets in the system (think Pacific Northwest), it’ll pool at the lowest point in the system, which is probably the caliper. If the caliper is full of (or has a high content of) water, it’ll boil at a relatively low temperature and cause a loss of braking. Keep the rotor/pads/caliper cool, and it won’t boil. Shimano is a proud and technologically advanced company, so they sweat this stuff.

I’m totally not advocating for DOT fluid over mineral oil, or vice versa. Both have their advantages and disadvantages. It’s just that this bike has Shimano brakes, and I thought I’d ramble about ’em for a bit.

Tangent over.

The wheels are Roval CL38, and they’re pretty darn nifty. They’re Roval-branded DT350 hubs (excellent value!) laced to nice 32mm deep, tubeless-ready carbon rims. FTW! At the time of this writing I have 28mm tubed (!!) tires on the bike. Maybe that’ll change. That’ll probably change. But that’s life right now.

Other stuff on this bike includes the Red/Quarq crank from my Tarmac, a Bontrager carbon handlebar, a Specialized Phenom saddle with carbon rails (woah!), Time pedals and a Garmin 520 with a stock mount. Here we are. Finally. What’s this rig weigh? 19lbs, 1 oz. That’s with the bottle cage, the Garmin, pedals and the strap for a Flare R taillight. 19 lbs, 1 oz? Jeepers! Where is all that weight? Trust me, I’ve been looking for it.

Despite the way this post is going, I’m not a weight weenie. I can’t remember what my Tarmac weighed, but I think it was somewhere in the 16 lb range. Why is this bike 3 lbs. heavier? I attribute it to three things, each of which might take an equal share. One is the frame. Our suppliers, smartly IMO, have gotten away from quoting bike weights. But most of them will say, “We’d estimate that a carbon frame is about a pound less than its aluminum counterpart.” So there’s a pound. But wait! We’re also talking a rim brake carbon frame to a disc brake aluminum frame. It’s probably more than a pound. Especially since my Tarmac was one of those fancy S-Works things.

Di2 is only a bit heavier than a mechanical system, something like three ounces. Hydraulic disc is rumored to be about a pound heavier than an equivalent rim brake system. It might be worth noting that we’re comparing Ultegra hydraulic disc to SRAM Red rim brake. It’s probably more than a pound.

Empirical data (the scale in my garage) shows that the CL38 wheels/tires/tubes/rotors/cassette is exactly 14 oz. heavier than the 303s similarly decked out. With that, I think we’ve found the three pounds.

Are we digging in enough?

Interesting enough, most of this excess weight looks like good weight. What? Yeah. Good weight. Weight that doesn’t rotate. And if that weight does rotate, it’s close to the axis of rotation and thus has a small angular momentum. This is the sort of nerdulation (my word) that’s occupied a lot of mindshare in the shops as we discuss gravel bikes, particularly gravel plus (650b with wide tires) vs. a more traditional setup (typically 700c with <40mm tires). Stay tuned on excess weight.

Can we talk about riding the darn thing? We can.

The Allez Sprint was initially marketed as a crit bike — stiff as hell, faster than greased lightning and aluminum so you can crash all day without demolishing your bank account. Guess how much this appealed to yrs trly. Not at all. And yet, some number of years later… here we are.

My first and most worrisome thought was that the handling would be so quick that I’d put myself on the ground before I got out of the driveway. Such is not the case. The handling is indeed quick, but it’s not spooky. FYI: I am a long, long way from the world’s best bike handler.

Stiffness? Yes. Punishment? No. We do live in Michigan and ride on Michigan roads. I found the ride completely acceptable. Like a magic carpet? Probably not, but just fine. Connected. Quick. A bit rough when the road was rough, but such was my expectation. I probably had a bit too much pressure in the tires, but it still wasn’t bad. It’s fun and peppy and I like it. It doesn’t hurt that it looks like Specialized picked the paint colors for Pedal.

The big question is: what do you want? If you’d like to save a few bucks, the new aluminum bikes (this Allez and the various Trek ALRs) with nice drivetrains look super good. If you want to ride more than me, maybe a more distance-oriented geometry would be good. If light weight is important, maybe carbon is good. Maybe rim brakes are a consideration.

I will say this: as you ride stiffer frames, tire quality becomes ever more important. This bike has pretty good tires. I have great confidence that really good tires, especially really good tubeless tires, will provide a significant improvement. Please stay tuned.