Aluminum bicycle frames are usually made of lengths of tubing, joined together at the ends by welds. The CNC eFanes electric enduro mountain bike is different, though, in that its frame is milled from solid 6061 aluminum … and it costs €15,999.90, or about US$18,630.
Manufactured by German bike company Alutech, the CNC eFanes' frame is appropriately enough created via a CNC (computer numerical control) milling process. In a nutshell, this technique involves utilizing a computer-guided milling machine to build items by selectively removing material from a solid block.
In the case of the CNC eFanes, the two sides of the frame's main triangle are milled as two separate pieces. These are then welded together clam-shell-style, so there's a weld seam running laterally down the center of the frame.
That seam isn't as noticeable as typical aluminum welds, though, due to the use of a special shielding gas that allows the welding to be performed at a lower-than-usual temperature – this means the metal doesn't become as distorted as it would otherwise. Additionally, the weld line is completely polished away on the top of the top tube.
According to Alutech, the CNC milling process – while not cheap – does make it possible to precisely minimize the amount of aluminum included in parts of the frame where it's not needed. As a result, the frame is lighter than one made via conventional methods, while still maintaining sufficient strength.
That said, the complete bike still tips the scales at a claimed 21.15 kg (46.6 lb). Keep in mind, though, that weight includes a Shimano bottom bracket motor and 504-Wh battery (upgradable to a 630-Wh unit). It's actually a pretty good figure for an electric mountain bike that's designed for enduro riding.
Some of the CNC eFanes' other features include a Fox Float suspension fork and rear shock; a 12-speed SRAM XX1 Eagle AXS wireless electronic drivetrain; SRAM Code RSC hydraulic disc brakes; DT Swiss carbon-rim wheels (29-inch in the front, 27.5 in the rear); and Maxxis tires.
If you have deep pockets, you can order a CNC eFanes now via the Alutech link below.
And no, it isn't the world's first bike to have a CNC-milled aluminum frame. The German-made Frace F160, for example, also has one, although it's joined together using titanium bolts instead of welds.
It is pretty.