Fizik Cyrano Carbon 30.60mm seat post

Announcing the Fizik Cyrano Carbon 30.60mm seat post!


Frame builders now have a high quality carbon 30.60mm seat post to fit directly into 31.70mm seat tubes with 0.8/0.5mm walls, such as Columbus Life part # SLFM13635 and XCr # XCRM13635.

The 31.7 seat tube with 0.8/0.5mm walls is typically used with the Crescendo (Formerly Slant6) and Cadenzia lug sets for XL (double over size) tube dimensions. While there is a USA made alloy seat post, the clamp has no set back thus placing the saddle 15 to 20mm further forward to the seat tube axis presenting serious frame design implications in the majority of circumstances.

Since 2004, I have sourced, used, and supplied a specially made in the USA 30.60mm seat post that fitted directly into a 31.7 diameter .5mm wall seat tube with no need for shims or sleeves. Unfortunately, the US manufacturer ceased making seat posts so a rethink of supply was required.

After consultation with fellow members of the “The Frame Builders’ Collective “ we agreed upon a list of Design and form requirements for a new 30.60mm seat post:

After discussion with fellow member of The Frame Builders’ Collective Dave Kirk, we agreed to look for a new supplier and agreed upon a list of Design and form requirements for a new 30.60mm seat post:

  •  A carbon tube post (a performance product Is required, so keeping the post under 250 grams was desired)
  • The post must have an accurate 30.60 – 30.55mm diameter shaft and be appropriately round. (+ – .05mm) This is very important to us as an accurate round to size post ensures firm clamping in the seat tube and avoids shaft distortion and possible cracking/failure when the seat tube binder boss is tightened. Moulded posts have problems with accuracy, but they are cheaper to make in large quantities. A precision ground carbon tube is the correct solution.
  • Length 330mm. Long enough for sloping and level top tubes. (easy to trim if the full length is not required when assembling the bike)
  • The post must have a suitable amount of rigidity so it does NOT behave like a fishing pole under the rider when pedalling.
  • Two bolt clamp system for easy micro adjustment of the seat angle and the saddle angle can never move even in very harsh conditions.
  • Designed to work with standard 7mm round rails, as well as rails with an oval cross section up to 10.3 mm which is often used on modern saddles.
  • A wide lower clamp thus increased contact surface between clamp and rails. This reduces the cantilever forces on the saddle rails and avoids failures.
  • Low profile upper clamp for low slung saddles.

Dave Kirk and I contacted several bicycle parts makers about the project, then the Fi’zi:k Cyrano seat post caught Dave’s attention at a bike show. This post looked very promising, ticking off on all the desired features. Dave made contact with Fi’zi:k. Fi’zi:k is an Italian company (Selle Royal), so to ensure communications went smoothly, Dave and I contacted TFC member Dario Pegoretti and asked that he also make contact with Fi’zi:k. Dario had considerable input into the new project as he also needed seat posts for his “Day is Done” lugged frame using the Cadenzia lug sets and Columbus tubes.

Prototype seat posts arrived from Fi’zi:k. Perfect! We could not ask for any better. All the desired features were met and the post looks nice with its subtle graphics.

The button to commence production was pressed and posts are now available, so frame builders now have a correctly designed high performance and well-made 30.60mm seat post option to use direct into 31.7 diameter 0.8/0.5mm seat tubes

Cheers

Darrell McCulloch
Dave Kirk
Dario Pegoretti

  

 

designed by: todd@consumedesign.com