Nor Cal Bicycle Marketplace

The last two days were spent at the Nor Cal Bicycle Marketplace - basically a very small version of Interbike. Lots of interest was generated around the 29" frame displayed there - here is a photo of the beautiful weather in Berkeley, CA.


New Website Launch

Check out the new look of the Ahrens Bicycles Website


Wavy Gussets

To spread stress over a larger surface area and improve joint strength, wavy gussets are used. On this frame, the custom gussets have been reworked to reduce weight while retaining their nice looks. The finishing touch has to be the nickel plated head badge securely attached with two button head screws.

Paragon Disc Dropouts

Rear dropouts are from Paragon Machine Works and have been re-machined to save weight. Hope Mono Mini brakes are standard with a larger 180mm rotor in the front for improved stopping power.

Steel APEX Trail Bike

Here are some photos of my personal steel APEX trail bike. This custom frame has slack geometry and a nice mixture of steel tubing and machined frame components - see details below:

TT/DT = Reynolds 853
ST/HT = Columbus Zona
Chainstays = Tange Prestige (superb steel MTB chainstays that are very rare these days!)
Seatstays = Nova Wishbone Style
BB Shell/Rear Disc Dropouts = Paragon Machine Works

Head Angle = 70 deg
Seat Angle = 72 deg
BB Height = 12.5" with 2.1" tires Chainstay = 16.77" level to ground Machined Head Tube = 5.25"

The build kit is fairly conservative with a 2007 Fox F100 fork, XT cranks, XT front/rear derailleurs, XT pods, XTR ti rear cassette and Crank Bros Twin Ti egg beaters. Easton EC70 carbon bars and post (Thomson post is temporary), Easton EA70 stem, WTB Pure V SLT saddle and ExiWolf 2.1" tires complete the package.

Special thanks to the Crazy F*ckin' German Tahn Von Rehmer at Willow Glen Bicycles for the light wheel build using Sapim CX-Ray bladed spokes, Hugi 240 rear hub, Paul disc front hub and Velocity Synergy rims. The current weight of this complete bike is 24.5 lbs with plans to upgrade to Hutchinson Air Lyte tubes and EC70 carbon post. Stay tuned for ride report #1 coming soon...


Low Rotating Mass

Total Weight = 25.9lbs...not bad for such a big bike with Hope M4 brakes and 200mm rotors! A chunk of weight savings comes from the custom hand-built wheelset by Tahn Von Rehmer at Willow Glen Bicycles:

Front Wheel
Hope Pro II hub w/Maverick 24mm axle conversion kit
Velocity VXC 29er rim
Sapim CX-Ray spokes
Brass nipples
Three cross lacing pattern

Rear Wheel
Hope Pro II hub
Velocity VXC 29er rim
Sapim CX-Ray spokes
Brass nipples
Three cross lacing pattern

Wheelset weight = 1740g...this is over 100g lighter than many pre-built wheels on the market! Thanks Tahn for such a sweet build.

Modular Frame Components

The machined parts on the rear triangle (upper/lower yokes + rear dropouts) can also be used to produce a 26" hardtail with XC geometry, slalom/dirt jumping geometry and even single speeds! This technique saves valuable time during the build process while providing greater design flexibility.

Machined Head Badge

First the head badge is machined from a thin sheet of 2024 aluminum. After that it is bead blasted to remove any milling marks and then hand-formed to the head tube's contour. Once the forming is done, the badge is nickel plated for a truly durable finish and understated appearance.

Clearance Where It Counts

This 'universal' XT front derailleur has been modified by removing the bottom-pull mechanism since it was not needed. The result is excellent tire/seat tube/front derailleur clearance - enough for almost two fingers to fit!

Revolver 29er in Black Chrome

Here are some photos of a black chrome Revolver 29" frame recently built. This has to be one of the nicest aluminum frames anyone could ask for. Easton Ultralite tubing in the front triangle, machined dropouts/yokes and square stays in the rear triangle, and a high-end build kit that requires deep pockets. This frame experienced a two-stage powdercoat, sticker application, then liquid clear-coat for a smooth finish.