Rear wheel not sitting flush with hub

[BrettJ]

Has anyone come across where the inside face of the wheel does not sit completely flush with the hub. My first concern is safety and the second is getting the wheel to sit straight on the hub. Please can you view the two videos, the first (

) is where I use paint on the hub and bolt the wheel on, you'll see the paint doesn't get transferred to wheel which proves it doesn't make contact. The second (

) shows that both the inside face of the wheel and the hub are straight.

[aerobod - near CYYC]

I would suggest the wheel needs a 45 degree chamfer relief of 1mm or so to avoid the slight radius at the base of the hubcentric boss.

I have seen the problem before with wheel spacers that don't have a proper chamfer relief that causes the wheel to not sit absolutely flat. We had a brand new M2 Comp at a track day last year that lost a wheel at 150km/h when the wheel stud kit it had fitted had all the studs shear off due to a wheel spacer with this issue, luckily with only a small amount of body and brake damage and no crash.

[Jonathan Kay]

Is the mating surface of the wheel bare metal or painted or powdercoated?

Are those closed wheel nuts well away from bottoming out?

Jonathan

[Dan R]

Some paint on the raised part of the hub with the same repeat experiment would prove or disprove the theory?..... or even paint over the raised part and the flat part as per the first video, then you would see exactly where the contact points were? 

[Jonathan Kay]

"I would suggest the wheel needs a 45 degree chamfer relief of 1mm or so to avoid the slight radius at the base of the hubcentric boss."

"Some paint on the raised part of the hub with the same repeat experiment would prove or disprove the theory?..... or even paint over the raised part and the flat part as per the first video, then you would see exactly where the contact points were? "

Could that test that?

Thanks

Jonathan

[BrettJ]

@aerobod, this is my thoughts too that either the wheel hasn't been machine correctly or the hub. However the wheel does has a small chamfer, but clearly not enough.

@ Jonathan, the matting surface of the wheel is bear metal. With regards to the nuts, I don't believe this to be the problem and the wheel is rock solid when bolted on and CC supplied the nuts.

@ Dan, I did think about this too, but as the wheel does have a small chamfer already, I can see that there is already a ring around the hubcentric boss that is about halfway (depth wise), which made me think is because of the chamfer that is doesn't go all the way to the face or the hubcentric being too big. If I had to paint the hubcentric boss, I don't think this will give me a true reading due the chamber on the wheel.

 

[SLR No.77]

Brett, early on in your second video, looking at the inside of the wheel there's very clear contact from the hubcentric boss, it's noticeable as a very shiny purchase mark which would suggest that James' comment is correct. Using a flap wheel lightly in the bore of the wheel to relieve the clearance (or lack of) could solve this, however your car looks very new and completely standard components therefore this should be reported to Caterham. It is a safety issue and might affect more cars with the same component combination.

Stu.

[BrettJ]

@ Stuart, Yes I have just sent an email to CC as my car has only 300 mile on the clock. I just wanted the wider audience's opinion before I did.