1G Accord Lug-Centric Hubs and Wheel Vibration

Pulling a wheel from my 79 Accord for the first time I was surprised to see that there was no wheel mounting flange on the hub. This means that the 1G Accord uses a lug-centric wheel mounting system. That is, it depends on the wheel studs to carry the full load of the car and the lug nuts to accurately center the wheels on the hubs.

Most (or maybe even all) modern cars have an axle hub design that includes a flange or collar that matches the oem wheel center bore. This insures that the wheel is always mounted precisely centered and the flange also helps support the load of the car through the axle and onto the wheel. Generic aftermarket wheels generally have a large bore so they will fit over the flange on a variety of different makes of cars, since various manufacturers size their hub flanges differently. That's why hub centering rings are recommended with aftermarket rims. They effectively reduce the center bore of the wheel to match the diameter of the hub flange.

But the hubs on a lot of older cars were not made with hub flanges but instead rely on a lug-centric mounting system. These cars rely on the tapered wheel nut to center the wheel accurately. While this can work fine, it may be less precise than a hub-centric system, especially if the lug nut seats on the wheel are damaged. This also means the wheel studs are subject to the full load of the car, unaided by a hub flange.

To insure vibration-free operation, especially at higher speeds, extra care must be taken when mounting lug-centric wheels. Most advice I have found on the Internet suggests snugging down the lug nuts with the wheel off the ground, followed by torquing the nuts to spec once the car is back on the ground. Following the usual standard practices like tightening in a criss-cross pattern is also necessary.

I have also read that a special procedure is required to correctly balance a lug-centric wheel and tire but I don't know if this is common knowledge down at the tire store.

All this came up because I just bought a set of RS Watanabe Eightspoke rims and was looking into hub rings. That's when I pulled a wheel to measure the mounting flange diameter. Well...turns out I won't need hub rings because of the design of the first generation Accord hubs. I would be curious to know when Honda introduced hub-centric wheel hubs on the Accord.

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The lugs don't actually support the weight of the car. If you forget to tighten them, you'll find out very quickly that they aren't up to the task. After a few miles, the lugs will shear off and the wheel will continue bouncing down the road while you grind to a stop. I think the static friction of the wheel surface clamped to the hub surface is what carries the weight.