Craig Calfee started building carbon frames in 1987, when “plastic bikes” weren’t very popular. Greg LeMond discovered Calfee’s bikes in 1991 and that meeting introduced Craig into the world of fussy professional racers. Being a custom frame specialist, Calfee became familiar with the limitations of sizing programs and adjustable fitting bikes. Framebuilder Bernie Mikkelsen had been working on a better sizer for many years when Calfee proposed to help bring it into production. A deal was struck and now there is a steel fabrication corner in Calfee’s carbon fiber frame shop. That is where the Calfee Sizer is produced. Now it’s easy to obtain the exact geometry needed for a custom frame.

Made here in our shop in California. Designed by Bernie Mikkelsen, this sizing cycle is made for ease of use and ease of understanding by the person being fitted. The technician can quickly and easily adjust all the important dimensions with quick releases and a hand crank top tube extender. The top tube extender is especially handy for the rider to feel the effect of a longer or shorter top tube while the technician turns the crank handle.

You can duplicate the geometry of any manufacturer’s production frame directly from their published geometry charts. This allows the rider to test ride a demo bike that may not fit perfectly just to get an idea of the ride quality. Then they can check the fit of the correct size frame and get the right stem length and saddle position on the first try. This makes special ordering frames easy and risk-free.

You can also use it to simulate different possible stem lengths on a bike in stock and change the actual stem only once on the stock bike.

  • Quick and accurate custom fittings
  • Easy to use by almost anyone in the shop
  • More added value for production bike sales
  • Roll a bike up next to the sizer and compare it directly to proposed changes
  • Add a power measuring device and conduct performance optimization studies
  • Communicate measurements quickly and accurately to the custom framebuilder

Adjustments that can be made directly:

  • Seat tube angle (from 71 to 79 degrees)
  • Seat tube length (from 43 through 72 cm)
  • Top tube length (from 46 through 70 cm)
  • Head tube angle (70 through 75.5 degrees)
  • Head tube length (8 through 30 cm)

Additional measurements that can be taken directly:

  • Wheelbase
  • Front center
  • Stack height of headset and spacers


A la carte Pricing:

Sizer frameset (no bike parts) $2,150
Parts kit: 26″ Wheel and rubber, chain, chainring & bolts, cog & spacers $325
Adjustable cranks (155mm to 185mm) $425
Saris Fluid2 Resistance Unit $60
Salsa Size-O-Matic Stem Sizing Tool $150
X/Y Fitting Reference Tool (optimized for ease of use with Sizer Cycle) $350
RacerMate Computrainer bracket (allows mounting of Computrainer resistance unit) $75

Financing is available, contact us for details.

Sizer Warranty

Calfee Design warrants against all defects in material or workmanship for Calfee Design produced parts for a period of one year from the date of purchase.

  • This warranty does not cover normal wear and tear, normal maintenance items or any damage, failure or loss caused by:
    • Accident, misuse, neglect, abuse or improper maintenance.
    • Structural modifications made by anyone other than Calfee Design.
    • Failure to follow instructions or warnings in the owner’s manual.
  • This Warranty is applicable to the original purchaser only.
  • This Warranty does not cover separately sold products including wheel, tires, chain, seatpost, crank and bottom bracket. Please address any warranty claims to the respective manufacturer.
  • Calfee Design will, at its option, repair or replace a defective product. Dealer labor charges are not covered by this warranty.
  • Calfee Design is not liable for incidental or consequential damages. Repair or replacement of defective products is the sole remedy under this warranty.
  • If you elect to repair a damaged or defective Calfee Design product through a source other than Calfee Design will not be liable for the defect(s) or damage caused by such repairs.



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