BMC TMR01, Part II

BMC TMR01, Part II

What’s in a name?
BMC loves it’s jargon. Me, less so. I tend not to be a fan of fancy names, crazy acronyms or technology monickers that do nothing to explain the tech in objective terms. But I run very little in the world and no one asked me so if you’re looking at the TMR01, you’re going to have to put up with p2p X subA. The first part, p2p, stands for “position to perform” and it’s a reference to the TMR01’s seatpost that allows the seat clamp to be placed in one of three positions—0mm, 15mm or 30mm setback. It can fit anyone from an old-school roadie to a triathlete hoping to achieve a more forward position on the bike. The change can be made with a single 13mm wrench.

SubA refers to the frame’s aero profile. It’s the use of the tripwire shapes and truncated tubes to give the bike its aero profile. To show you just how all-business this frame is, BMC went with a recessed seat binder accessed through a small window in the top tube and into which a small rubbery cover is pushed. So, p2p X subA stands for the combination of the rider’s fit with the bike’s aerodynamics. It’s the suggestion that there’s a synergy at work, and in that regard they aren’t wrong.

BMC says relatively little about just what varieties of carbon fiber they use in the frame. There’s one mention of high modulus carbon fiber, which is as surprising as the rising sun. While I’ll get to the ride of the TMR01 soon enough, I can say that the ride of this bike is too good to have been accomplished with only intermediate modulus carbon. Another detail that points to the use of some high modulus carbon is that BMC claims the weight for a 54cm frame is 1100g. I reviewed a 58 and didn’t have the opportunity to tear it down for a weigh-in, but I’m willing to believe that 1100g for a 54 is pretty accurate.

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Sugar Substitute
Everything that scientists have come up with to replace sugar—corn sweetener, saccharine, aspartame and all the others—have failed to duplicate the full effect of sugar, both in terms of satisfaction and biological function. We remain, rightfully, suspicious of the alternatives. Aerodynamics is less fraught with trouble.

While having the aerodynamic profile of a falcon would be fun, it can’t make up for actually pedaling the bike. You still need to be able to go. The thing about a bike like the TMR01 is that for those of us who used to be faster than we currently are, a bike with an aero profile like this can make it seem like you’re training more hours per week. I know this for fact because my fitness hasn’t been stellar and this bike gave me a gear any time I was north of 20 mph. It was like fitness flattery.

Of course, the effect of an aero advantage is really only apparent if you’re switching back and forth between an aero and a non-aero rig. If you have but one bike, it’s just going to become your bike and even though the relative advantage will disappear under thousands of miles, it’s like a good diet and will deliver dividends even when you’re not aware.

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There is one point I need to clarify with regard to this bike’s aero advantage. Part of my experience with this bike’s ability to escape the wind had nothing to do with the frame. The TMR01 was equipped with Zipp 60s, the company’s more affordable deep-section wheel set. In broad strokes, it’s fair to say that a pair of deep-section carbon wheels will offer an aero benefit comparable to an aero frame. Combine the two and you’ve got an advantage that’s noticeable even at relatively low speeds. So while this review isn’t about the Ultegra Di2 group or the Zipp 60s that were included with this bike, those wheels definitely had an impact on how quick this bike went.

Those brakes hidden beneath the cover in the fork and below the chainstays are linear-pull brakes—V brakes. This was the bike’s one feature that was not completely sterling. Yes, they were easy enough to adjust and clean, but they didn’t offer great modulation. It’s possible that playing around with different pad compounds would make a difference, but braking power was rather progressive, not as linear a response as most of us have come to enjoy.

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A Grip on Fit
BMC offers the TMR01 in six sizes. I’m pleased to note they haven’t gone with the silly convention of calling bike sizes small, medium, large—seriously, what could be less meaningful? The sizes are 48, 51, 54, 56, 58 and 61. Those sizes work out with fit numbers like so:

  • Size, Top Tube, Stack, Reach
  • 48cm, 51.5cm, 50.5cm, 37cm
  • 51cm, 52.5cm, 52.5cm, 37.8cm
  • 54cm, 54.2cm, 54.5cm, 38.6cm
  • 56cm, 55.3cm, 56cm, 39.2cm
  • 58cm, 56.6cm, 58cm, 40cm
  • 61cm, 58.3cm, 60.5cm, 41cm

The upshot here is that these bikes run slightly small. I often fall between a stock 56 and 58, but almost no one produces a 57, so I end up studying geo charts to figure out which bike is the better fit. And while I tried the 56 in the TMR01, it felt like I was on a 55, or something even smaller. At 56.6cm, the 58 has the shortest top tube for that size that I’ve encountered in a while. That’s not a knock. The stack, 40cm, allowed me to achieve a good fit with a minimum of spacers. The short-ish top tube is a natural response to the desire to allow riders fit flexibility with that seatpost. With the seat clamp in the rearmost position, that top tube would be too long for most riders were it 58cm or more.

Normally, when I review geo charts I find some gap in the sizing, some span of two centimeters or more that produces a blind spot in the size run. The practice of presenting stack and reach numbers gives better picture of the real fit because it does a better job of considering changes in seat tube angle. The sizing on the TMR01 is remarkably well planned, especially given its ability to accommodate both pro-style long-and-low fits as well as more forward triathlon-style fits.

Compared to many road bikes on the market, the TMR01 features handling that we might call leisurely. The 54, 56, 58 and 61 all have 63mm of trail. The 48 and 51 have 75mm and 66mm of trail, respectively. With a BB drop of 69mm, these bikes aren’t crit machines; they are definitely meant for someone who wants to zone out, put his head down and hammer. And honestly, at threshold, I think it’s usually a good idea to have a bit of understeer rather than oversteer.

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Yeah, but Is It Fun?
When you factor out racing considerations—the desire to be faster than the next guy—and going fast in order to be more fit, there’s still a compelling reason to go fast on a bike. It’s fun. Twelve is more fun than eight and 20 is more fun than 12. A big piece of the enjoyment of riding comes from that sense of the world whooshing by, right? Well that’s one of the keys to a flow state; it’s called a rich environment. As more and more sensory input comes at you, eventually it reaches a pitch that is overwhelming and your brain concludes that it can only focus on that which is absolutely necessary. The higher the stakes, the deeper the flow.

What’s important to remember is that you don’t have to be going the speed of sound to enter flow. Faster than usual is enough to increase the fulfillment from flow.

I’ve ridden bikes that are stiffer at the bottom bracket. I’ve ridden bikes that were more comfortable in the saddle. I’ve ridden bikes that were also fast, perhaps faster than this one. What I haven’t done, ever, is ride a bike that had as compelling a blend of features as this one. Sprinting on the TMR01 was a better, more satisfying experience than my experience with the Cervelo S5. It was also a good deal more comfortable; freeing those seatstays of a rear brake can make an appreciable difference. That the bike was this quick was a shock.

I’ve reviewed one other aero bike that was quick the way this is and still maintained some comfort and road feel; it also weighed in the same neighborhood—a bit less, actually. That bike was the Litespeed C1R. I liked that bike a lot, but on technical descents and under a full sprint there was a bit of lash in the frame; the wheels wouldn’t stay in plane with each other. The practical effect wasn’t that I felt like I couldn’t sprint on the bike, it was that I tended to back off my out-of-the-saddle efforts just a bit in order to focus on keeping the bike pointed exactly where I wanted it to go. The TMR01 didn’t have that issue.

The TMR01 is a remarkable bike, one that offers a lively feel along with terrific stiffness. It’s a combination of features that I honestly didn’t expect from BMC. Why not, I’m at pains to say. Though I’ve had high regard for their work, the constellation of features was something that, perhaps, I thought was beyond their engineering team. Let’s not forget that this is their first aero road frame (even if it is an adaptation of the TM01 time trial frame), which is all the more impressive when you consider how many frame designs Cervelo has been through.

Were I buying a carbon fiber bike right now, it would almost certainly be an aero road frame. Why not capitalize on a feature of the material steel and ti can’t touch? And in making my short list of bikes that I’d consider for purchase, I’d put the TMR01 in my top three choices. It’s that good.

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11 comments

  1. Alex

    Hi Padraig,

    Big fan of your work. You finish with saying that the TMR01 would be part of your top 3. That’s a pretty impressive statement!

    I really enjoyed your review of R3 vs. S3 and as a Cervélo retailer it has helped us justify our similar feelings of aero vs. traditional “like bikes”. They also both respectively outsell any other road bikes we sell.

    What would be your top 3 bikes?

    1. nate

      I can only hope the Felt AR series and the Parlee ESX, only because I think they would be interesting reviews.


  2. Author
    Padraig

    Alex, Bruce: Regarding my other two, I don’t really want to go into print (pixels) just yet. I have suspicions, based on what I’ve seen on paper, but I have yet to put real miles on the other two bikes. I know I’ll be on one fairly soon. I hope to get on the other later this year. And at the rate things are changing, I expect I’ll have to revise that statement in two or three years.

  3. Les.B.

    I’m assuming that descents are a lot faster with an aero frame.
    I hear-say that braking with carbon wheels is compromised.
    So, I’m wondering if descents take a new level of caution with the combination in this bike.
    With my limited knowledge and experience, it seems to me that one would need to descend more slowly to keep in a safety zone.

    1. J Cloyd Britt

      Most brand specific non-first generation carbon wheel failures due to heat/warping are pretty well known now. But yeah, I don’t ride them. I’ll say it’s due to safety issues, but really what I mean is I’m too poor.


  4. Author
    Padraig

    Les.B: Because wind resistance is a squared function, the faster you’re going, the bigger the advantage an aero bike and aero wheels will give you. As a result, descents are definitely faster. The wheels I rode on this bike had aluminum brake tracks, so to the degree that braking wasn’t all that it could be with this bike, it wasn’t because I was riding carbon clinchers, because I wasn’t. On a slightly different note, the improvement in carbon clinchers is such that if you’re using the right brake pads, descents needn’t be tricky. The one thing I didn’t do on this bike was check my descending. I never took it down Tuna or Las Flores, but I did plenty of descent in the Palos Verdes Peninsula and the handling on the TMR01 was solid.

  5. Hoshie99

    Linear pulls take a little modification of pressure at the levers due to their “heavy on” tendency. I suspect you would adapt to those quickly.

    I have found they can be very powerful if setup right but at first you need to be careful with your force at the levers are they can lock up easily.

    Did you find them strong enough with BMC’s design? Did you feel like it was liveable long term if you owned the bike?

    J

  6. Sam

    Having tested a few aero bikes back to back with their lighter counterparts (Venge/Tarmac, TMR01/SLR01), I’m afraid I still do not know what the hype’s about. But then these are just short test rides and I’m no professional bike reviewer, that’s why I keep coming back here, to find out what’s possible, rather than what is apparent.

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