Wheels Coming Loose on Track

[...]

Have you checked you have the right bolts for your new wheels , because thats what should be centring your wheels and the reason they are tapered and you should always cross tighten ?

i bet the wheel bolt angle is not right for your new wheels

 

[mad in general]

Was wondering whether anybody else had had problems with this, or if I'm being fed a load of BS..

I bought a brand new set of 15x7" Team Dynamics PR1.2 several weeks ago, and fitted them for the first time at Oulton Park on the 4th June. I had an absolutely miserable day, as the wheels came loose on all 4 corners after only a few warm-up laps! I had the wheels off & on in the pits 4 times checking everything, and even tried 3mm spacers just to be sure there was clearance, but nothing seemed to work. Eventually I went with 32mm long wheel bolts (26mm supplied by TD) torqued up to something bloody ridiculous and managed to get a few sessions in the afternoon. Even so, the car was wandering and rumbling despite the bolts still being tight! I had noticed the front spigot rings were a very sloppy fit on the hub spigot and there was 0.5 - 1.0mm of movement, but whether that was down to the wheels coming loose, or whether the wheels coming loose was down to the failure of the rings I couldn't be sure; however, it was my hunch that the rings were at fault.

I had an incredibly frustrating phone call to Demon Tweeks the following day, trying to explain to the girl that I had tried everything and that there was nothing wrong with the car.. I won't go in to detail of that too much! But she did eventually agree to have them shipped to TD for inspection. I called to chase a few days later and was told the plastic spigot rings they had supplied were the wrong ones - too short, apparently - and that the wheels would be shipped back to me with the deeper rings fitted.

I had pleaded with Tweeks to get me a new set of wheels with the bores machined directly to fit, without these pathetic little plastic bits, but they refused and assured me it would be ok. My next track day is coming up at the 'ring in 2 weeks, so understandably I am very reluctant to have plastic anywhere near my wheels!

Has anybody had anything similar? Particularly with TD wheels and plastic spacers? I'm going to machine up some aluminium spigot rings just to be safe, but it would be nice to hear any other accounts of wheels repeatedly coming loose.

Have a read of this thread, pay particular attention to my discussion with chip. He explains it perfectly.
http://www.cliosport.net/forum/show...g-center-bore-of-alloys&p=9443499#post9443499

As a side note, what's happened with chip?

 

[McGherkin]

i bet the wheel bolt angle is not right for your new wheels

I suspect this too. Mismatched taper = fraction of the frictional locking.

 

[aucky]

As a side note, what's happened with chip?

30 day ban.

 

[CamMoreRon]

60Deg taper is basically an industry standard. Try buying a set of Grayston bolts / nuts and you'll see the only options are 60Deg taper or radius seat (obviously the latter are for radiused seat wheels, never for a conical seat).

A tapered seat shouldn't be relied on for centering the wheels, either. There is friction between the bolt taper and the seat, so as the bolt is tightened it will never be able to pull the wheel absolutely concentric to the hole; this is why all modern vehicles have hub-centred wheels - i.e. a spigot with close-running tolerance. The tapered seat helps to align the wheel rotationally so that the bolt is roughly concentric to the wheel pilot hole, while the spigot ensures the wheel is absolutely concentric to the hub - the latter being the most important factor. People may have run without spigot rings by accident, but I really doubt that you'd get away with that with any serious track use.

WRT bolts in shear.. the holes in wheels are over-size and when the bolt is seated properly it will be concentric to the hole through the wheel, so there will be clearance all round the outside (round the outside). That means that under normal conditions there is never any shear force in the bolts, only tensile load from the torque, so it is impossible that the bolts would ever be sheared without the wheel having slipped against the clamp face. I'm sorry to be anal, but from the thread linked above it seems to be a common misunderstanding that the bolts are loaded in shear!

Some good info here: http://www.eng-tips.com/viewthread.cfm?qid=351384

As one of the posters on Eng-Tips said: because the amount of stretch on a wheel bolt is very minimal (0.05mm) any paint on the wheel's bolt seat will wear off and remove this stretch entirely, causing very rapid torque drop-off. Once the bolt torque has dropped you have zero clamp load and are effectively relying on just the hub spigot (because of the bolt hole clearance I mentioned earlier) to take all vertical & longitudinal loads in the wheel. Obviously if you have a plastic spacer ring in there, that is not going to have a hope of taking those kind of loads, especially at high temperature, so I think this may be the root cause of the problem!

The seats on my wheels were painted, and when I inspected them before sending back to Team Dynamics the paint had been rubbed off the majority of them. I think the paint being rubbed off caused torque drop on the bolts, which then lead to the failure of the spigot rings. This fits with what happened at the end of the day when I torqued the bolts up to 130Nm and experienced no torque drop but still had vibration at speed - the extra torque stretched the bolts enough to counter the paint wear (on what little paint was left at this point) but the wheels were not concentric to the hubs any more as the spigot rings were a sloppy fit.

So my solution will be to fit the machined spigot rings I get from Team Dynamics and to carefully sand down whatever paint is left on the wheels' bolt seats.

 

[mad in general]

fitted them for the first time at Oulton Park on the 4th June. I had an absolutely miserable day, as the wheels came loose on all 4 corners after only a few warm-up laps! I had the wheels off & on in the pits 4 times checking everything

Can I just pick up on this. I was always under the impression that once wheel bolts are torqued up you should re check them after say 50 miles or so. Less when on a track I would guess.

So, first time round I would expect them to work loose. Torque them again and no issues.

I think your problem is that when you have taken the wheels off again and refitted you'd then need to go through that same process again. If you have taken them off multiple times then I would expect to have to complete that same process multiple times.

In effect is it possible that you have engineered this situation by removing the wheels/bolts instead of just re-torqueing?

I am no engineer but the above is my understanding.

Hope this makes sense.

 

[CamMoreRon]

The wheels were torque checked when I left for Oulton Park in the evening and again in the pits the following morning before going out on circuit.

 

[Coops Mk1]

i'll repeat, I have run, on track with no spigots for entire trackdays on full slicks with no issues whatso ever.

and by the looks of things you have come to the same conclusion as to what was at fault and that's the paint on the bolt seats on the new wheels.

 

[aucky]

When you say bolt seats, do you mean the female taper on the wheel bolt holes?

I encountered this last year. The paint was 'melting' and just wasn't providing enough friction. I sanded the paint off with a dremel wire brush attachment and have had no issues since!

 

[mad in general]

When you say bolt seats, do you mean the female taper on the wheel bolt holes?

I encountered this last year. The paint was 'melting' and just wasn't providing enough friction. I sanded the paint off with a dremel wire brush attachment and have had no issues since!

Yes I believe that is correct.

 

[mad in general]

The wheels were torque checked when I left for Oulton Park in the evening and again in the pits the following morning before going out on circuit.

Ok mate, was just a shot in the dark.

Hope you reach a resolution.

 

[mad in general]

while the spigot ensures the wheel is absolutely concentric to the hub

Sorry, one last thing. AFAIK, unless it was an interference fit then surely when you place a wheel on the spigot it would be suspended from that and there would be a gap at the bottom. Therefore the wheel would not be centralised to the hub.

 

[CamMoreRon]

i'll repeat, I have run, on track with no spigots for entire trackdays on full slicks with no issues whatso ever.

Why did you run without spigots?

One man's blind luck is another man's catastrophic failure, so I wouldn't go recommending people to run with spigots that don't fit or none at all! You might have got away with it, but you were very lucky IMO.

Yeah the paint is looking more and more like what started the problem off. My mate has just bought a new skateboard, so I reckon I'll wrap some of his excess grip tape (basically sticky-back sand paper) round the seat of an old bolt, weld that to a bit of bar, stick it in my power drill and use that to clean the remaining paint off the seats.. that way the seat stays a nice uniform shape.

 

[CamMoreRon]

Sorry, one last thing. AFAIK, unless it was an interference fit then surely when you place a wheel on the spigot it would be suspended from that and there would be a gap at the bottom. Therefore the wheel would not be centralised to the hub.

True, but the clearance is about 1 tenth of f**k all, so isn't going to matter.

 

[mad in general]

True, but the clearance is about 1 tenth of f**k all, so isn't going to matter.

I may come across like I am trying to catch you out, I assure you this is not the case. I am trying to learn from you as I believe I have seen your build thread on pistonheads and I am in awe!

Have you checked what clearance you currently have? surely if its about "1/10th of f**k all" then it'd be fine?

Dave.

 

[Coops Mk1]

Why did you run without spigots?

One man's blind luck is another man's catastrophic failure, so I wouldn't go recommending people to run with spigots that don't fit or none at all! You might have got away with it, but you were very lucky IMO.

they break, I lose them, couple of sets of wheels I have I never even got any for for the exact reasons mentioned of them breaking or going walkies, I run stud conversion on one of my cars so no need to centralise the wheel to put bolts in.

to say its luck I would call misguidance, they are not the reason for your wheels coming loose and they do not make a car in anyway dangerous or likely to fail. ime they are purely to centre the wheel to make putting the bolts in easier. the bolts themselves and the frictional clamping force provided at the mating face of wheel to hub by the bolts is what holds your wheel in place and load bears. the spigots do naff all.

I think on this we're going to just go round in circles so agree to disagree etc etc.

either way I hope you sort the issue as its quite an alarming experience

cheers

Ben

 

[CamMoreRon]

I may come across like I am trying to catch you out, I assure you this is not the case. I am trying to learn from you as I believe I have seen your build thread on pistonheads and I am in awe!

Have you checked what clearance you currently have? surely if its about "1/10th of f**k all" then it'd be fine?

Dave.

It's ok I know you're just asking questions! I haven't checked the new plastic rings yet, but I'm going to shelf them and just use the metal ones I get from Team Dynamics instead. I'll check the clearance before fitting.. with any luck they'll be a push fit in the wheel and a close fit on the spigot, but we'll see.

they break, I lose them, couple of sets of wheels I have I never even got any for for the exact reasons mentioned of them breaking or going walkies, I run stud conversion on one of my cars so no need to centralise the wheel to put bolts in.

to say its luck I would call misguidance, they are not the reason for your wheels coming loose and they do not make a car in anyway dangerous or likely to fail. ime they are purely to centre the wheel to make putting the bolts in easier. the bolts themselves and the frictional clamping force provided at the mating face of wheel to hub by the bolts is what holds your wheel in place and load bears. the spigots do naff all.

I think on this we're going to just go round in circles so agree to disagree etc etc.

either way I hope you sort the issue as its quite an alarming experience

cheers

Ben

Fair enough, I think you're right that the spigots are not *normally* relied on to take the load, and that certainly seems to be the opinion of our hub engineer. They are critical for centering the wheel though, and you can't rely on the bolts to do that by themselves.

In case it got lost in my mega-post I don't think the spigot rings were what caused the failure any more. After talking to various other engineers it looks much more likely that it was torque drop on the bolts because of the painted seats, and the spigot ring becoming enlarged was a secondary failure.

 

[mad in general]

It's ok I know you're just asking questions! I haven't checked the new plastic rings yet, but I'm going to shelf them and just use the metal ones I get from Team Dynamics instead. I'll check the clearance before fitting.. with any luck they'll be a push fit in the wheel and a close fit on the spigot, but we'll see.

Fingers crossed they get them sent sharpish then.

Best of luck mate.

 

[Ph1 Tom]

Yes the spigots are critical for centering the wheel but dependant on the vehicle itself (how sensitive it is due to geometry etc.), centreing capability of the wheels bolts/nuts and the torquing sequence the centreing of the wheel is a variable.

They take no load. Think of it as a bolted joint and being a 3rd bolt in the middle of 2 outer bolts. The two outer bolts take the load, the centre takes no load and is redundant (is most cases). If you want to go into depth on the subject I can recommend some text books

If you go for studs and nuts choose a high temp, high strength compound but be very careful how much you use, just a drop will do otherwise you'll have fun and games taking them out. If you use a lot and find its easy to remove then you're using the wrong compound. Also give them 24 hours to 'cure' before fitting wheels, it gives the strongest bond.

 

[George@RTR_Parts]

When you say bolt seats, do you mean the female taper on the wheel bolt holes?

I encountered this last year. The paint was 'melting' and just wasn't providing enough friction. I sanded the paint off with a dremel wire brush attachment and have had no issues since!

I had this aswel on track using powder coated F1s, did the same as you Jack and it sorted it


Hope OP gets sorted before your upcoming ring trip

 

[CamMoreRon]

Thanks, I'm pretty confident that it'll be sorted now.

 

[CamMoreRon]

An update on this..

I got my machined spigot rings from Rimstock, only to find they were ~1mm too small for the wheel bores, so spent the afternoon before my 'ring trip machining up a set that fitted properly. I also removed what remained of the paint from the tapered bolt seats.

The bolt torque problem is now 100% fixed and they don't have any torque drop, which is nice! I was getting horrendous vibration over 90mph though, so took them to the friendly tyre bloke at the DN track day for balancing.. the fronts were 40g out per side and the rears 15g, which the bloke said was f***ing awful for a new set of wheels and just shows how well Rimstock "inspected" them when they were sent back! So 30EUR later and the car was perfect for the rest of the trip. On recommendation from the tyre guy I increased the bolt torque to 120Nm to give them a little extra stretch for track abuse.

So moral of the story: if your wheels come with painted bolt seats, REMOVE THE PAINT.

Moral #2 is not to believe any salesman BS about how "experts" have "thoroughly inspected" your parts.