March 24, 2017

Profile’s Tech Tip #12: What is a Profile No Boss Crank?

When we initially brought the Spline Drive sprocket design into Profile and Madera’s inventory, we had to back track a little to make an aesthetically pleasing counter part: Profile’s No Boss Cranks.

What is the difference?

Profile’s Standard 19mm RHD Cranks have a spider boss on the right arm.
Profile’s Standard 19mm LHD Cranks have a spider boss on both the right and left arms.

Though both of these above arm combinations WILL work with a Profile or Madera spline drive sprocket (The boss butts right up to the sprocket’s edge), we created “No Boss” cranks to offer a cleaner look considering you no longer need to use the spider bolt.
For a visual, here’s a Profile Standard 19mm RHD Crank on a Madera Spline Drive Helm Sprocket.
And here’s a Profile No Boss 19mm Crank on a Profile 19mm Spline Drive Sprocket.

There is, however, something to consider when buying Profile cranks: If there is a chance that you will be switching back to a bolt driven sprocket in the future, we would advise staying on either RHD or LHD cranks as those will be compatible with any sprocket (spline or bolt driven).

March 24, 2017


We are taking precautions to protect our employees and follow CDC and state guidelines. In the meantime, our machine shop is still running, we're here to assist you and we'll be shipping product to help support bike shops during this difficult time.