Are the 700 series wheels lug or hub centric? Without tightening the lugs there doesn't seem to be much, if any, play around the hub, but I've always thought they were lugcentric. Thanks!!

According to your definition, every car I've ever owned (Volvo or otherwise) would be LUGcentric. I'd be surprised that a wheel balancer would need a special adapter for THAT type. I'd sooner believe the opposite.

The information I received from The Hunter Engineering rep is that "most" newer cars are hubcentric, with the implication that the hubcentric wheels are correctly centered on a balancing machine using cones through the center bore. He stated that for lugcentric wheels there are "fingers" that attach to the balancer that correctly center the wheel. My guess is that it frequently doesn't matter since the lug circle is usually very close to being concentric with the center bore, but there's no guarantee that they will always match up. The following is the address for a Hunter web page that locates a rep in your area: http://www.hunter.com/pub/company/findrep.htm. You might want to give him a call to verify the information. Thanks!!

I found the following text at http://www.tomorrowstechnician.com/tt/tt40224.htm:

The way in which a wheel is mounted on a balancer will not only affect the accuracy of the balance job itself but also the repeatability of the balancing results. Worn mounting cones or shaft bearings may be the problem. Using the wrong type of cone can also give inaccurate results. So too can dirt on the wheel or nicks in the wheel center hole. But another often-overlooked cause is using the wrong mounting technique for the type of wheel.

The basic idea is to mount the wheel on the balancer the same way it is mounted on the vehicle. A pilot hole centric wheel (one where the center hole positions the wheel on the hub and prevents it from wobbling sideways when the lug nuts are removed) can be mounted on a balancer with a cone from the backside.

But a lug centric wheel (one that does have some sideways movement when the lug nuts are removed) requires a different balancer-mounting procedure. A lug centric wheel must be mounted with a cone from the backside and an adapter flange plate against the front side. The fingers on the flange plate must be properly positioned so they line up with the lug holes in the wheel. This is necessary to center the wheel on the balancer shaft. If this is not done, you may just be going through the motions of balancing the wheel because the results won’t be accurate or repeatable.

i have no idea what this means, but thought i'd ask for an explanation just in case someone else is also not familiar with the terminology. :)
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'

As I understand it, the terminology refers to the way in which the wheel is centered on the hub. If the center bore through the wheel mates with the hub to provide the centering, then the system is hubcentric. If, on the other hand, the bores for the hub studs are used to center the wheel, then the system is lugcentric. In a lugcentric system, the lug nuts, tightened against the lug nut recesses in the wheel, center the wheel on the hub. Not a meaningless distinction (I hope): some wheel balancers (the Hunter GSP9700, for one) need an accessory to properly center lugcentric wheels. The different systems may also come into play when considering aftermarket wheels, in that, the systems should be compatible. I'm right at the outer edge of my competence envelope, so I'd welcome any replies. Thanks!!

so can you tell by just removing your wheel?
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'

Not sure. The bore through the wheel is "just about" the same size as the protruding section of the hub, and I'm not certain of what I'm looking for. If the 700 series system is hubcentric, it doesn't seem to be very robust. If it were hubcentric, I guess I'd be looking for more secure fit when the wheel was mounted, even without the lugs nuts installed, but that's just a guess.

hrm, i'm still confused about this whole thing. all i know is that the lug nuts on my volvo are beveled on one side, and that side should be facing in. when i tighten them up, the bevel portioned pushes into the slightly large holes of the wheels to properly seat the wheel onto the hub.
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Kenric Tam
1990 Volvo 740 base sedan (B230F)
My Volvo 'Project'