BMC Race Machine RM01
The BMC RM01 reminds us of old-school pro bikes, even with all the modern touches and materials. Back in the day, you could get a bike with pro geometry in different Columbus tube sets. Columbus SLX if you wanted the pro copy, maybe Columbus Max if you wanted a stiffer bike that was for bigger riders. Columbus SL if you wanted something a little cheaper and a little more flex. You could get it in even heavier tubes, like Cromor or Thron, if you just wanted the pro geometry and a pro-esque paintjob.
There were some fictions about the old way. The big one was that the bike under the paint was actually built by the person or company with the name on the down tube. Pro riders were often getting their preferred builder to design and execute the frameset and then sent the completed tubes to the bike sponsor for painting. When the old 7-Eleven team was in existence and riding Huffys that were nominally built by Serotta, Andy Hampsten had Landshark build his frames. This supposedly ended when Eddy Merckx took over the team and made some custom bikes for the riders who wanted them.
Today, thanks to the fact that carbon-fiber is the preferred frame material and molding is the preferred fabrication method, it's nearly impossible to have custom geometry and it's even harder for a rider to substitute his favorite builder's work for his bike sponsor's.
We bring the classic pro bike line-up conceit because the RM01 shares a geometry with the SLR01, BMC's ProTour-level frameset. It's more than just sharing the geometry. They are sharing most tubing profiles as well. It is like the old bikes, a pro bike that has just been stepped down a bit for cost savings and a little extra weight.
Not that the weight penalty is much. Our 55cm test bike weighed in at 15.32lbs without pedals and the "stock" BMC build. The wheels are the relatively heavy Easton EA70. The rest of the build is mostly SRAM Red, including the Red BB30 crankset, but swapping in the cheaper Force brakes. Stem is FSA and bars the carbon-fiber Easton EC-70 Ergo. Swap in carbon-fiber tubulars and you have a bike at the UCI weight limit. On the flip side, we added Speedplay Zero pedals, Arundel Mandible cages, Blackburn mini-pump, powertap wheel, Garmin 500 computer, and seat bag with tube and tools, and the weight moves up to 17.12lbs. This weight might be more relevant to most cyclists, as this is probably close to how most will experience it, not stripped down for the final kilometers of Monte Zoncolan.
When sizing up this bike, we were surprised by the head tube height for a given size. Our regular aluminum race bike has a 56cm top tube and a 15.5cm head tube. If you get a 56cm top tube in the RM01, you're looking at a 17cm head tube. For a pro bike, at this size, the head tube is pretty high, though this isn't quite "century" geometry as the top tube, seat and head angles, and fork rake are identical to the 2010 ProTour-level SLR01, and the only geometry change is the RM01 has a 2mm taller head tube. As we prefer a long-and-low position, we're already using a low-stack top cover (FSA's term for the dust cap that sits on top of the upper headset race), and no spacers and a 120mm 84-degree stem, we needed to make some changes to fit the RM01.
In order to get low enough in front, we swapped in a 120mm 73-degree stem. We briefly considered taking the headset cover off completely, as the lowest stock cover is 10mm and thought we wanted to get lower. We heard there was a 8mm cover available, but couldn't find one. In 2010, Cadel Evans and a number of the BMC team riders rode without a cover to get their stems low enough on their SLR frames. This was solved in 2011 with the Impec having a slightly shorter head tube for the given frame sizes. And some riders, like Rabobank's Oscar Freire, have their mechanics fabricate a custom cover. However this web tool for determining the third leg of isosceles triangles indicated that we probably could use about 8mm between the 10mm cover and stem.
There is an advantage to having more head tube and no stack spacers. It results in a stiffer front end. Wider tubes, as in the head tube here, resist twisting forces better than narrow tubes, as in the steerer reinforced with spacers. And the 1.5cm of extra head tube is probably lighter than corresponding 1.5cm of extra steerer tube and spacers.
The second surprise of sizing the bike was the BMC seat post. The post is strong and light (and proprietary), a classic two-bolt design that is easy to use, but it has 5mm of setback. Even with a 73.5mm seat angle, we got close to the limit of rearward travel of our saddle. If you have super-long femurs and prefer to sit pretty far back in relation to your cranks, you might not be able to get there from here.
We also needed to make one change to really do the test right. We needed to pull the SRAM Red BB30 crankset. We wanted to put in our SRAM Quarq Cinquo so we could better correlate ride feel with power numbers. So we picked up the Wheels Manufacturing SRAM/Truvativ BB30 Adapter, pulled the stock crank and installed ours. We'll have a review of the adapter in the near future.
Rolling out the door for our first ride, the bike felt light. Getting out of the saddle, even for easy stretches, felt powerful. Potholes didn't seem to go through us as they would with our aluminum frame. All of this was good. What the bike didn’t feel was terribly fast. Fast is a vague term, but it's also about that sports car thing. Even if we aren't driving 200kph, we like the idea of sensing we're going fast. It was a puzzle.
We've long been interested in how bikes are designed to be really stiff in one plane but not so stiff in another. BMC makes a big deal of their Tuned Compliance Concept (TCC), the idea that the bikes can resist all the pedaling forces we can give but can give on the inputs from rough roads. BMC calls attention to this in their print ads featuring George Hincapie. The large text reads, "The worst thing about the Spring Classics is the cobblestones. Well, that's what the others say." Flat-footed prose at best, and the ad is outdated, but the idea that a stiff bike can make the ride over the stones softer is worth investigating.
We sought out pavé and rode it. Sometimes this meant a narrow strip on the edge of black top roads where the old stones peek through. Sometimes this meant 500 meters on cobbles. We also found local roads that were brutally scarred by frost heaves and snowplows the past winter and hammered those as well.
While we're still a little skeptical of TCC-type claims in general, the BMC rode great over the rough stuff. What we were feeling at the handlebars and saddle was much less extreme than when we ride our other bikes on the same road surfaces. Occasionally, there was loud snapping noise and we feared some tube had fractured, but never did that happen, nor did anything rattle loose, nor did a water bottle ever get ejected.
That it does well on the stones is another way the RM01 is an old-school racing bike. Geometry was, and still is, partially dictated by road conditions and they used to be rough by modern standards. Back in the day, it was one bike for all conditions, and for most of us, that's still the case. Pro racers have a large quiver and can select for conditions, but in the real world most of us can only go with one bike for everything. Might as well be comfortable on bad roads, especially if it entails minimal cost in terms of lost efficiency anywhere else.
In terms of stiffness for the rider-created inputs, the bike was impressively stiff. Taking it for sprint workouts, we seemed to notice the stiffness both at the handlebars and on the upstroke in all-out sprint efforts. Since we're using our own power meter, it was reassuring that our max power numbers seemed to creep upwards when we were at our max thrashiest.
The stiffness also apparent in those out-of-saddle claws over 15% grades. Low gear, lots of torque, but even with the brakes close on less-than-perfect wheels, there was no rubbing.
Going down the other side of those steep climbs, the bike was easy to handle, easier than we expected. And it was spinning the big gears at 45mph that we started to reconsider our initial impression of the RM01.
A classic pro road bike is often one that is designed to be ridden for hours and hours at a time, for days and days on end. As such, comfort is an important consideration. So, too, handling. A bike that takes too much attention to ride forces you to focus on keeping the bike pointed straight, not putting power to the pedals. If you can find published pro bike geometries from the 80s and before, you'll see that lots of race bikes had pretty slack angles by today's standards. When LeMond first got involved in selling road bikes in the early 90's, his bikes had angles that were closer to a "sport-touring" bike than what many Americans considered race geometry.
This BMC seems to have geometry that comes out of this tradition. The head angle for the 55 frame we tested was 72.5 degrees. The fork rake is 40mm. It's a geometry that does straight lines well; you don't have to think about piloting, the bike goes. It's also one that is typically stable at high speeds. It still turns fine. The cost to this is that the bike doesn't feel particularly lively when going uphill. Even that is ok by us. We once took a cyclocross bike out on a mountainous road ride. Near the end of the ride, we encountered a descent where we accelerated to around 50mph.The 'cross bike took lots of attention to ride in a straight line at that speed. Not great for the particular conditions, but fine overall, as the 'cross bike was designed to turn quickly at speeds of 10-20mph.
If there was evidence that this geometry made us climb slower, we'd be concerned. But both our time and power data indicates no such thing. The light weight of the bike is a boon when the road tilts up, so we can deal with the bike not giving us a super-spritely ride when we're powering up a long 10% grade, as even there, the straight-line tracking is a plus.
Enjoy the different look, the complicated joinery and variety of tube shapes. The BMC RM01 is an attention-getter whether it's moving or standing still. Climb aboard and go for a long ride and the sizzle fades away as you're treated to a classic ride.