Hub centered rims and NON-hub centered rims

[seafish]

it involves putting a nut snug at the top, rotating the wheel 180 degrees and repeat. Once all the nuts are snug they are to be tightened down in three steps.

That's the way I mount all of my wheels, lugcentric or hubcentric.

 

[seafish]

Motorhead, did you ever get those hub adapters???

What size did you end up getting??

How did they work out for you??

 

[Motorhead]

seafish, I DID get the rings but I haven't got them on yet. I am going to exchange the chrome rims for the same pattern but polished. I went with the INSIDE diameter that Motorsport Tech had on their site for the AAM which is the same for the fronts too. I measured the ID of the wheels and sent them that measurement. I also have my Dads old Logan lathe if I need to do any small removal off of the OD of the rings. The guy did a beautiful job!

 

[seafish]

Those look nice...I'm going to order me some...how long did they take to get em done?

Motorsport Tech listed 121.30 mm for the Dodge AAM hubs, now I just need to measure my Ricksons...

 

[Motorhead]

seafish, I happened to get my order right when they were making a "Run" of rings. I think it took a few weeks. I would find someone with an INSIDE micrometer to accurately measure the Ricksons. I would measure each wheel. I can say for SURE that when I had the tire store first mount the tires and wheels, I had a light bumpy ride. When I got home, I jacked one wheel at a time, loosened all of the lugs and very carefully retightened ther torqued the wheels back on. This was done BEFORE I had the rings made. Smooth ride thereafter. I guess what I am saying is that even though the wheel manufacturers say that being hub centered isn't necessary, I think that they are wrong. I believe that the Ricksons are 5.15" ID but don't hold me to that. You want the rings to press fit the wheels and have a SNUG-SLIDE fit on the ID of the wheel to the hub.

 

[AH64ID]

Let me ask this... (could be fun with the current thread status).

Are the OEM rims in fact hub centric on a SRW?

Reason being is they use, as we all know, tapered lug nuts which will do the centering. If the hub did the centering the lug nuts should be the flat washer type, as used on a DRW.

What is the wheel bore diameter on the DRW wheels? I found a couple sources at 121.4mm, but nothing official.

Not trying to stir the pot more, but a 1.7mm gap with coned lug nuts tells me (not a wheelologist) that the OEM wheels are lug centric. I am not sure you could get .85mm of flex out of the studs with 8 properly torqued cone lug nuts to 135 ft/lbs. IF you where to get a road hazard to smack the wheel hard enough to get that flex I am not sure the tire would recenter on the lugs, there is a LOT of clamping force in play.

If the OEM wheels where hub centric why don't the Vision Type 81's come in the OEM diameter of 123mm? They are only for GM and Dodge applications and GM uses a 116.7mm hub, so 123mm would still fit both applications. 124.5mm, Type 81 bore diameter, seems pretty damn exact and I would think they used that size for a reason.

OK, back to the DRW talk. They ARE most certainly hub centric, with flat washers and all. Looking at the Vision wheels for DRW trucks they are setup as 121.4mm, that's a 0.1mm clearance on the OEM hub. A 0.05mm, 0.002", gap will most certainly transfer weight to the hub with flat/washer lug nuts.

I think it's pretty clear that SRW is lug centric and DRW is hub centric, and the numbers and lug design are what tells the story. The SRW wheel just has a tighter clearance for installation ease, not because it is hub centric.

Just thinking out loud.. so flame on, but short of something new I don't see the SRW being hub centric as many claim.

 

[Prairie Dog]

I can tell you that the wheels on my SRW fit snugly around the hub and I've had both metal and aluminum wheels. We don't have the salt issues that some of our eastern brethren have either so rust doesn't seem to be the cause of the fit.
Frankly, and all I know is what I've seen on my own trucks, I think both the lugs and hubs carry the load.

 

[AH64ID]

I can tell you that the wheels on my SRW fit snugly around the hub and I've had both metal and aluminum wheels. We don't have the salt issues that some of our eastern brethren have either so rust doesn't seem to be the cause of the fit.
Frankly, and all I know is what I've seen on my own trucks, I think both the lugs and hubs carry the load.

Mine fit "snugly" as well, but at 1.7mm of clearance I don't think they fit nearly as tight as 0.1mm clearance on DRW wheels.

 

[brods]

You might find this thread interesting. http://www.eng-tips.com/viewthread.cfm?qid=351384

Tmoose,

Have just joined this forum and this is hopefully still be a useful response to your earlier post. I've designed a lot of wheels with conical and flat nut seats over the last 35+ years and I was part of the SAE subcommittee that created SAE standards 2315 and 2316. In answer to your question:

* Conical nut seats are typically set in a Belleville washer boss that greatly facilitates stress distribution and torque retention. Steel wheels also have a secondary Belleville washer effect as the entire mounting pad is lifted in the center.
* Conical nut seats also provide a mechanical stop to wheel rotation during severe vehicle handling maneuvers. Required wheel clamp load is typically defined by using a "clutch theory" where clamp load keeps the wheel from rotating. In the real world, applied torques and corresponding clamp loads are often not controlled, any wheel slip is a failure, and this can be a very real concern.
* The actual wheel to hub joint is far less robust than most people think. Actual stud stretch is only approx .05mm (.002") and any amount of dirt, etc that interferes can cause real concerns very quickly if the wheel is loaded aggressively.
* Because of the limited stud stretch, any paint on the nut seats of aluminum wheels is a serious no-no an must be avoided. This is also very true of nut seats on the class 8 and 9 heavy commercial vehicles.
* Steel inserts were mostly seen on early aluminum wheels that generally weren't heat treated and use a hypo eutectic alloy. Most current cast wheels use A356 heat treated to T6 and the only issue is getting sufficient bearing area.
* Hub-centric is dominant to reduce installed assembly runout. You would be correct in noting a potential centering conflict with the conical nut seats. This is a secondary concern that most people just tolerate. Some European designs us a bolt with a spherical nut seat to potentiall minimize this effect.
* For class 9 commercial vehicle, many users ahve adopted the "Pac-nut" which gives a beneficial Belleville washer effect.

I don't know when conical seats appeared in steel wheels, but I'm certain it was pre-1950s, and for the torque retention and stress distribution benefits that the design offers.

Hope this helps

 

[Prairie Dog]

They fit as snugly as the brake rotors. (There's a whole new subject for ahem, discussion)

 

[AH64ID]

They fit as snugly as the brake rotors. (There's a whole new subject for ahem, discussion)

How much corrosion do you think is in there from a life with 0.85mm of gap?

Like I said, it's going to be very hard to convince me a conical lug with 1.7mm difference in hub dia and hub bore is hub centric, when the same hub is used with flat washers and a 0.1mm difference is 100% hub centric design.

 

[seafish]

Just an update to let you guys know that I finally installed the hubcentric rings that I got from Motorsport Tech.

Sorry, no pics, but they fit both the oem rear hubs, the Dynatrac front hubs and the Rickson forged aluminum heels PERFECTLY with a light press fit. They also in no way impinge on the BalanceMaster wheel balancers that I use between the wheel and hub. Overall, I am extremely impressed with the quality and fit of these T6 alloy machined rings. When I reinstalled the Ricksons, it was easy to see that the lugs were perfectly centered in the wheel holes even before I put any of the lug nuts on. While I still carefully tightened the lug nuts using my normal routine-- in a star pattern with no weight on the wheels torqued first to 90#, then torqued to 120# in a star pattern with only enough weight on the wheels to keep them from spinning, then a final around the clock torque to 135# when the truck is on the ground. They definitely add some easiness and piece of mind when installing the Ricksons. While it did take about 3 weeks to get them, due to the fact that they were a custom order size, Motorsport Tech customer service was friendly and informative.

I did use antisieze so that I can remove them later if I want, but I don't really see needing to that...where they sit on the hub in no way prevents any maintenance issues.

 

[Motorhead]

Seafish, Do you think that the "Rings" did anything to smooth out the ride? I haven't put the rings on my fronts yet as I have to change out the EMS hubs to the DynaTrac's. I DID put them on the rear wheels and definitely felt a smoother ride.

 

[seafish]

Seafish, Do you think that the "Rings" did anything to smooth out the ride? I haven't put the rings on my fronts yet as I have to change out the EMS hubs to the DynaTrac's. I DID put them on the rear wheels and definitely felt a smoother ride.

Haven't driven near enough yet to feel a difference and the roads I drive are so dam shoddy that it is likely I won't feel a difference until I get out on the highway if I do at all. I have always been very careful when installing my wheels and lug nuts, so I am not at all sure that there even will be a difference, but like I said, I DID notice that with the hubcentric rings, the wheel lugs readily centered in the wheel holes even without any lug nuts on yet, as opposed to the way I use to snug the lugs in order to center the wheel before finishing the wheel install. So far, I LIKE them ALOT, well worth the minimal investment in time and dollars to install them.

 

[AH64ID]

How easy will they be to remove?

The ID of my Vision's and OEM wheels are different, and I use them both each year.

 

[seafish]

I used antisieze on both the hub, ring and wheel center, so they ought to pop off with not much trouble...the press fit was snug, not tight on both the hub and wheel center.

That being said, I do NOT live or travle much where they "salt" (or whatever cr*p they use nowadays) the roads in Winter, and I guess if you do there could be an issue, as there is not much to grab on the adapters, they would have to be pried off.