Published by Tristan on 01 Mar 2009 at 10:57 am
Eyeletted vs Non-Eyeletted Rims
The Past
Back when bikes were steal and breasts were real all high-quality aluminum rims used steel eyelets. Eyelets provide the rim with a larger contact surface for the spoke nipple which traditionally helped to reduce cracking around the nipple or the nipple pulling through the rim. As a nice side effect they often allow the nipple to rotate easier while building the wheel.
Eyeletted and non-eyeletted rims
There are two types of eyelets; single eyelets and double eyelet:
Single Eyelets
The eyelet is a small circular steel band which is pressed onto the rim after the spoke hole has been drilled. A single eyelet only covers the inner wall of the rim.
Eyeletted and non eyeletted rims from inside - impossible to differentiate
Double Eyelets
Double eyelets are also known as “sockets.” In this case the eyelet extends from the inner wall of the rim to the outer wall of the rim. Double eyelets are heavier however they generally do a better job of preventing the nipple from pulling through as they spread the load of the spoke tension to both walls of the rim. Visually the only way to tell if eyelets are single or double is to remove the tyre, inner tube and rim tape and examine the outer wall of the rim.
Single and double eyeletted rims
Pros and Cons of Eyelets
As with any rule there are exceptions, however generally speaking eyelets:
- Decrease the chance of the rim cracking around the spoke nipple
- Allow the spoke nipple a greater range of rotation
- Increase the ease of building the wheel
- Increase the weight of the rim
The Present
The quality of aluminum alloys and the ability to extrude them has improved dramatically in recent years and as a result there are modern high-quality rims which do not have (and do not need) eyelets. There are good rims with eyelets and poor rims with eyelets, and conversely there are good rims without eyelets as well as with them and in my eyes it doesn’t matter. The rim should be chosen on it’s overall quality and reputation, not by whether it has eyelets or not.
A Few Examples of Good and Bad Rims
DT RR1.1 single eyeletted rim
DT Swiss RR1.1 single eyeletted road rim. After being released 4 years ago these 420 gram rims quickly received a reputation for cracking, especially when used on the rear wheel. As a result DT Swiss produced a 480 gram double-eyeletted version which is recommended for rear wheel use. These rims build up really well and are beautifully true however I don’t see the value in an expensive, heavy rim which has poor aerodynamics and comparatively poor lateral stiffness.
Outland 390 gram eyeletted rim
An Outland Eyeletted rim. Does a 390 gram rim eyeletted road rim sound too good to be true? It is.
Kinlin XR-270 non-eyeletted rim
The Kinlin XR-270 is a non-eyeletted road rim which weighs around 455 grams, is amazingly stiff and durable, and has a semi-aero profile. The supplier for these rims has not had a single report of cracking around the spoke holes even on low-spokecount wheels with high spoke tension. This is a perfect example of a good non-eyeletted rim.
Alex R400 non-eyeletted rim
The R400 is another example of a great non-eyeletted road rim: 410 grams with similar lateral stiffness and aerodynamics to the DT RR1.1.
Alex Adventurer eyeletted rim
The Alex Adventurer is a 505g mountain bike rim with great stiffness and durability. It’s inexpensive and a great example of an eyeletted rim for low cost freeride / heavy use wheelsets.
Related posts:
Rae Merrill on 25 Nov 2010 at 1:15 am #
Interesting stuff. Always wondered he difference between eyelits and non-eyelits. I wonder if there is greater risk of corrosion with non-eyelitted rims?
Tristan on 25 Nov 2010 at 7:20 am #
Hi Rae. If the spoke nipple is coated in grease where it contacts the rim when built then it shouldn’t be an issue with either type of rim. In my experience I don’t think one is more prone than the other.