The Editor purchased this wheelset second hand. He spent a couple summers riding (not racing) on them in the mountains. At the end of that time a number or cracks in the rear rim were discovered. The full story follows.
This wheelset was chosen for two reasons. First, it seemed like the best value in the weight to dollars sense. Secondly, it utilized non proprietary components including traditional hub flanges and J-bend spokes. The second reason turned out to be important as the wheelset is salvageable despite a cracked rear rim. Here is what the Torelli website has to say about the Torelli Bormio Ceramic Ultra-Light wheelset:
Bormio Ceramic Ultra-Light Wheels
- 1380 grams per pair
- 380 gram rims, for low moment of inertia
- Rim depth 22 mm
- 0.9 x 2.2 bladed aero Pillar Sandvik stainless steel spokes
- Front 20 radial, 24 rear radial non-drive/2 cross drive side
- Traditional "J" spoke for easy maintenance
Along with the 6 ceramic sealed bearings, the free hub utilizes a ring of needle bearings in the freehub body/axle contact. This reduces friction between the rotating surfaces during freewheel decents. Hubs use compatible freehub bodies available in Campagnolo or Shimano/Sram. Wheelset weights are quoted with Shimano freehub bodies and rim strips—no corner cutting here.
Torelli recommends a 180 lb rider weight limit on these light weight road wheels.
Suggested retail price $650/pair.
The rims appear to be Kinlin XR-200. The Torelli website recommends a maximum weight of 180 lbs which more or less matches weight recommendations for the Kinlin XR-200. With a weight of just 380 grams these aluminum clincher rims appear to be on the light end of the spectrum. Specs for the Kinlin XR-200 rim:
XR-200 Niobium 22mm 700c Clincher Rim
- Weight: 380-387g
- Width: 19mm
- Depth: 22mm
- Drillings: 20, 24, 28, 32
- Colors: Black, SIlver
- ERD: 594mm
The cracks in the XR-200 rear rim eminate from the spoke holes. About one half of the spoke holes had cracks and the cracks affected both drive side and non drive side spokes. The small size of the cracks made them difficult to detect. It is possible that the wheel was ridden for many rides with these cracks before they were finally discovered. The image shoes, by size comparison with the spoke nipple hole, just how narrow these cracks were.
Instead of replacing the rim with the same extrusion a set of H Plus Son Archetype rims were ordered. These rims have an ERD similar to the existing Kinlin XR-200 ERD and the original bladed spokes could be retained. The Archetype is H Plus Son's version of the 'wider is better' or 'clinchular' 23mm wide rim. These rims are not light at about 480 grams each. Some of that weight comes in the form of a relatively thick spoke bed which is reassuring considering that is where the original rear rim failed. Here are the specs from the H Plus Son website:
Weight: 470 grams
Material: G609 Alloy
Height: 25 mm
Width: 23 mm
Machined Braking Surface
ERD: 595 mm
The perfect all around road rim. At 470 grams, this rim has proven to be light yet not sacrificing strength, stiffness, and stability. The well accepted 23mm wide profile mimics a tubular tire, where the advantage can be felt immediately while taking corners as the tire is no longer shaped as a light bulb, flopping over with high load. Our impeccable H Plus Son workmanship and our invisible welded rim joint comes standard with each rim.
The beginning of the process started by measuring spoke tensions as guidelines for the rebuild. Using the Park TM-1 spoke tension guage we found:
- Front: 15 +1/-0
- Rear drive side: 15 +1/-0
- Rear non drive side: 10 +1/-1
These are the actual TM-1 readings. If the Park lookup chart is accurate then the tension guage reading of '15' corresponds to about 130 kgf.
The included image shows a unique spoke nipple design. The spokes are aluminum and use a standard spoke form factor with the benefit of an 'inverted' design in the same nipple. The hidden, sometimes called 'inverted', portion of the nipple is in compression instead of tension which should make for a stronger nipple. Being aluminum they weighed in at .36 grams each. This is a fraction of a gram heavier than traditional aluminum spokes and seems like a good investment in nipple durability.
Specs measured while the wheels were disassembled:
- Used front rim 20 holes (Kinlin XR-200): 382 grams
- Used rear rim 24 holes (Kinlin XR-200): 373 grams
- Bladed spoke (front): 5.155 grams
- Special aluminum nipple: .36 grams
- Torelli front hub: 75.7 grams
- Torelli red rim strips: 19 grams
- H Plus Son Archetype rim 20 holes: 484 grams
- H Plus Son Archetype rim 24 holes: 483 grams
- Used Torelli Ultra-Light front wheel w/out rim strip: 586 grams
- Same front wheel re-rimmed with Archetype rim w/out rim strip: 670 grams
The Archetype rims build into attractive wheels. They were also easy to work with and trued up without any trouble. Of note is the affect of the wider rim on the effective width of the installed Michelin Lithion 2 tires in size 25mm. Installed on the original 19mm wide 'Ultra-Light' rims the tires measured 25mm wide. Installed on the Archetype 23mm wide rims they measured about 27mm wide. The resulting wheels are obviously no longer 'Ultra-Light' in name or mass.
At the time of this writing these wheels have not yet been fitted to a bicycle.