Spotted this rim with the nipple holes way off to one side. Does anyone know who makes these and why? My best bet is it has something to do with getting out of the way of the cassette in the back and the brake disc in front, but is that really worth it for the uneven force on the rim itself?
I can't really tell what brand the bike is.
by BattleFlyNate
5 Comments
Yes, many companies make an offset rim intended to be built into the rear wheel. It helps keep reduce (not eliminate) some of the spoke tension imbalance.
I don’t recognize what you have there, but I’ve built many wheels with these Velocity rims.
[https://www.velocityusa.com/product/rims/a23-oc-622](https://www.velocityusa.com/product/rims/a23-oc-622)
Off centre rim (OCR). The idea is you can build a stronger rear wheel because you don’t need as much difference between spoke lengths on drive side and non drive side (dish) to accommodate the sprockets.
It’s normal. Not uneven force the way you’re thinking about it. Just different spoke length.
Spoke tension (measured with a tool) is slightly different for each side on disc wheels.
That is called an A-symmetric rim. Most rim manufacture make some models like this. usually with a 3 to 6 mm off set but could be more/less depending on rim width.
Reason to to reduce the extreme bracing angle of the short side of the wheel(drive side rear/disc side front) to give a more uniform bracing and tension between the left and right sides of the wheel.
Dish is not affected and is still dished between hub center(except Cannondale AI frames), Is some extreme cases with super boost hubs I have even built wheels that had higher spoke tension on the non-drive than drive side. though such wheels are rare.
Its actually a design to make the spkie tension forces more even. The spoke flanges on a rear or disc hub are not equidistant from the center so spoke tension is inherently uneven. The spokes offset at the wheel helps even out that difference. The real question is, why aren’t all wheels made that way?