BH gave Road Bike Action an exclusive preview of the stunning G5 just as the first shipment was scheduled to arrive in Europe for the AG2R team’s assault on the Tour de France. The G5 is a replacement for the G4 (Read RBA's Review), and while it shares the integrated seat mast and slightly sloping top tube of its predecessor, the G5 is a completely new, ground-up design with every tube profiled to optimize strength. Like the G4, the new G5 is lightweight—810-grams for the 54-centimeter frame, and 13.4-pounds for the SRAM Red-equipped complete bike. With Shimano Di2 and Dura-Ace clincher wheels, the 56-centimeter test bike weighed 14.1-pounds with pedals. Blue, white and natural carbon is the signature graphic of the G5 (red is the second option).
BH contracted with a yet-to-be-named composite firm that was created to produce limited-production uber-elite carbon frames. BH is one of only two road bikes that will be produced there. The quality of the frame’s construction and painting details are self evident. The cable guides are bonded, faired into the structure and slotted—a carbon first. The underside of the downtube has the B signature channel to hide the cables and tuck the Shimano Di2 battery out of sight. BH uses a tapered head tube and fork steerer to boost rigidity and make a better transition from the one-piece fork blades through to the steerer tube.
 A tapered head tube and steerer make for precise steering. Internal headset bearings keep the BH looking sweet. The BH G5 fork is made by Edge Composites
 Inside the G5 head tube shows that the smooth layup is duplicated on the inside as well as the exterior of the frame. This is as good as carbon gets.
The entire front section: seat tube, head tube, down tube and the bottom bracket housing are molded in one piece and then bonded to the G5’s sleek rear section. Dropouts are all carbon and the rear derailleur hanger is a substantial aluminum piece where most offerings are spindly and flexible. A carbon fiber front derailleur mount is a weight saving feature that makes sense, because it is bonded into the frame—not glued on as an aluminum afterthought.
BH dropouts are carbon fiber, and the hanger is designed to take a beating.
The G5’s aero-profile seat mast uses a sweet-looking internal carbon fiber seat post. The two-bolt clamp never slipped.
In the tradition of BH, the G5’s chainstays are short and stiff. Tall and rectangular, the stay profile, in conjunction with the channelized downtube is said to boost bottom bracket stiffness 100-percent, while curved, D-profile seatstays and careful attention to the G5’s carbon layup procedure maintain a comfortable ride. While we are on the subject of stiffness, BH says that the G5 is 200-percent more rigid in the steering head, which was the only weakness we found with the B4.
A patented bottom-bracket cable guide allows the shift cable housings to be routed kink free to the opposite sides of the frame’s head tube. The cables cross over inside the guide. RC photo
G5 owners can choose between the standard BB30 press-in bottom bracket system, or with a pair of press-in adapting cups, use Shimano or SRAM’s press-in EX bottom bracket bearings. BH bonds in a thin aluminum bearing receiver to insure that the bottom bracket bearing tolerances are absolutely right on every frame.
A view of the press-in Shimano EX bottom bracket adapter that BH offers. Standard G5s use larger-diameter BB30 bearings that mount directly into the frame.
RIDING THE AG2R RACE MACHINE
B4 owners are going to cry if they get a chance to ride the new BH (I do and I did). The G4 is short-coupled and a bit harsh riding on rough pavement. The G5, by comparison, is smooth as silk—and without sacrificing any if the G4’s spectacular climbing. In fact, the G5 seems to lay down power more effectively, perhaps due to the fact that its seat angle is a half, to one full degree steeper than its laid-back sister’s. Where the G5 blazes ahead is while descending at speed. Here, the G5 feels much better balanced and combined with its smoother ride, provides turn and burn confidence. Hit a bump mid corner and the G5’s stiffer front end won’t waver.
 (Photo: Tri-Guy Bill)
Easy on the legs and the eyes, the BH G5 is the kind of racing machine that feels like you’ve owned it all your life on the first outing. Paint and decals are beautifully applied to the new BH. The G5 is a looker.
It’s tough to talk up a bike without finding something to nit pick, but the BH G5 is an exception. It is an outstanding performer with explosive climbing and sprinting performance—yet it is even tempered enough to allow a fatigued racer to don a wind shell or take a hand-up in a stormy cross-wind. AG2R will be well equipped in France.
INFO: www.bhbikes-us.com |