wire wheels and broken spokes

[bluegrass john]

I recently had my wire wheels trued and had new tires mounted on my BJ8; The wheels are Dayton 60 spoke chrome wire wheels which are approximately 10 years old with approximately 3000 miles on the car in the last ten years. After a drive of approximately 65 miles I noticed one of the spokes on the front wheels was broken. After inspecting all the wheels no other broken spokes were found. I was curious as to why the spoke broke and if there is anything in particular I can do to prevent this from occurring again. The tires and wheels provided a very smooth and comfortable ride after the wheels were trued, balanced and new Michelin XAS 180x15 tires were mounted: never had a broken spoke on any healey I have ever owned: maybe I have just been lucky. Any thought or ideas would be appreciated

Thanks,

John

 

[LarryK]

Probably a weak link. I would call Dayton and ask questions. Out of warranty, but I would think they can answer your question. Could be over tightened or hit by a rock ( guess ), but I would think the stainless spoke was weak and finally showed up, since it is not driven much.

 

[Bob_Spidell]

IMO, 60-spoke wheels are marginal on a 6-cyl Healey. My BJ8 had 60-spoke painted wheels when I bought it and I broke several spokes almost immediately (though the painted wheels do not have SS spokes there is some argument SS is more brittle than mild steel). Modern radials have much more grip than the bias-ply tires that came with the car; if you drive spirited at all you will probably continue to break spokes. 72-spoke chrome/SS Daytons solved my problem.

Again, just MHO.

 

[British_Recovery]

I would return to the guy who trued the wheels.

 

[Michael Oritt]

Bob Spidell said: IMO, 60-spoke wheels are marginal on a 6-cyl Healey

It's certainly a matter of taste--perhaps 72's are okay on a later convertible car but to my eye they look too busy on a roadster, either 4 or 6 cylinder.

FWIW I have never broken a spoke on my Dayton 60's in about 60K miles of spirited driving.

 

[Bob_Spidell]

Bob Spidell said: IMO, 60-spoke wheels are marginal on a 6-cyl Healey

It's certainly a matter of taste--perhaps 72's are okay on a later convertible car but to my eye they look too busy on a roadster, either 4 or 6 cylinder.

FWIW I have never broken a spoke on my Dayton 60's in about 60K miles of spirited driving.

I believe the 100s are considerably lighter than the 3000s; at least my BN2 feels much lighter--and more agile--than my BJ8. That may have something to do with the potential side loads that I think cause spoke breakage. Also, I don't think it's a matter of taste that 12 additional spokes produce a stronger wheel, but I don't have calculations to prove it.

 

[bluegrass john]

Not to confuse the issue but I have been asking all the local healey people and others who have had healeys for years about the broken spoke I experienced and so far I find the majority of the broken spokes have been on cars with Chrome wheels ( stainless steel spokes ); in fact one orginal owner of his BJ8 since it was new in 1965 has never experienced a broken spoke on the two sets of painted wheels that he has had on his car that has traveled over 100.000 miles. I spoke to another individual who is an engineer who worked with many different grades of stainless steel for a large American appliance manufacturer who tried to find out from Dayton what grade of stainless they were using for spokes but they declined to furnish that information. I am sure there are owners who have had a broken spoke on painted wire wheels but most of the car owners I talked to experienced spoke failure with the stainless steel spokes. Not sure if this means anything but I thought I would throw it in the mix to see what others thought!!

John

 

[Barefoot]

I bought my BJ8 in '85. It has chrome wire wheels (60's) that came with chrome plated spokes.

When I bought it, it had about 6 broken spokes. I broke several more in the first few years I owned it. Every spoke that has broken has been a short one. I could sometimes hear them break when I got on the gas. Most, but not all of the ones that have broken are on the left rear wheel (close to my ear). Every one has broken where the spoke shaft flares at the hub. Usually it leaves the broken part inside the hub, and you can't see that the spoke is broken on a casual look. Of course, plinking it with a finger or something is a dead give away for the broken spoke because it sounds very different.

I've always replaced the broken ones with stainless steel spokes. I think I've done maybe 18-20 spokes over 30+ years of ownership. I got pretty good at replacing them...

I've never broken a stainless spoke.

 

[Michael Oritt]

I believe the 100s are considerably lighter than the 3000s; at least my BN2 feels much lighter--and more agile--than my BJ8. That may have something to do with the potential side loads that I think cause spoke breakage. Also, I don't think it's a matter of taste that 12 additional spokes produce a stronger wheel, but I don't have calculations to prove it.

Bob is no doubt correct and i was referring only to esthetics.

 

[Keoke]

I am sure there are owners who have had a broken spoke on painted wire wheels but most of the car owners I talked to experienced spoke failure with the stainless steel spokes. Not sure if this means anything but I thought I would throw it in the mix to see what others thought!!

I think they got ah whole lotta bad stainless spokes in Kentucky.:smile-new:

ONTO H: I agree with bluegrass- John & others 100%.--

N Michael- the look of 72 spoke SS wheels just grow on ya after a while N they don't need truing or break spokes-:glee:

 

[blueskies]

May having the wheels trued have caused the broken spoke? There likely is no way to prove that one way or the other, but the shop that did the work may give you a break seeing as they recently worked on the wheels.

Spokes, including the originals, do break. I have a pile of old Healey wheels that prove that point. However, wheels with spokes missing do come in handy as spoke donors for other wheels.

 

[tahoe healey]

I have had about eight spokes break on my painted wheels over the years. Almost all on the right rear wheel. Three years ago I purchased used chromes and one came with a broken spoke. No problems since. I am planning to replace all the tube-less with tubes so I can adjust the spokes as needed. One of my tube-less has a slow leak.

 

[Randy Forbes]

A little clarification is in order here; chromed wheels did not always use stainless steel spokes. At some point, and I don't pretend to know exactly when (late 80s-early-mid 90s?) was the shift from chrome-plated steel to polished stainless spokes.

If we have a resident metallurgist here, he can explain why on a molecular level, but the plating process was widely speculated to cause hydrogen embrittlerment, leading to the spoke's fractures.

I know that when you're comparing fasteners (like bolts__and why you do not use ss in a stressed/loaded application like your suspension) then stainless is softer than steel (which is why it's so easy to gall 316 stainless threads, unless an anti-seize is used). A softer alloy is not as likely to break as a harder alloy, so I don't think it's correct to say that the stainless spokes are harder than painted, or plated steel ones. I'll go on record saying I don't think stainless is more brittle, just the opposite.

I'm also under the impression that there are far fewer broken spokes on the chrome wheels of today, including the last couple of decades, compared to the chromed wheels of say the 60s-70s era.

The wheels on my car were constructed January 2010, and so far, all spokes ring with a ping, and I'm not particularly easy on them.

 

[Bob_Spidell]

When I was trying to solve exhaust leaks at the manifold/downpipe flange I bought SS studs, thinking they MUST be better because, well, just because. After snapping a couple I went back to mild steel studs, which have held up fine.

 

[Randy Forbes]

When I was trying to solve exhaust leaks at the manifold/downpipe flange I bought SS studs, thinking they MUST be better because, well, just because. After snapping a couple I went back to mild steel studs, which have held up fine.

Not to pick nits, but snapping would infer, to me anyway, a clean break; did they actually twist off, or reach their elastic limit (elongated/reduced diameter, etc)?

(I'm asking, not arguing, really )

 

[Bob_Spidell]

Elastic limit, I believe. Trying to stop the leak, I was torquing them down pretty good--by hand, not with a torque wrench--and they broke almost flat with the manifold flange. I had anti-seize grease on them so was probably putting excessive 'stretch' on them.

 

[Randy Forbes]

Elastic limit, I believe. Trying to stop the leak, I was torquing them down pretty good--by hand, not with a torque wrench--and they broke almost flat with the manifold flange. I had anti-seize grease on them so was probably putting excessive 'stretch' on them.

Okay, that still falls in line with what I was saying about stainless being softer than steel.

 

[Keoke]

Elastic limit, I believe. Trying to stop the leak, I was torquing them down pretty good--by hand, not with a torque wrench--and they broke almost flat with the manifold flange. I had anti-seize grease on them so was probably putting excessive 'stretch' on them.

Yeah BOB:

You jest stretched the out of em---------layful:

 

[Bob_Spidell]

I think SS, at least some types of it, are known to be more brittle than mild steel. I bought the studs from Doug Reid, IIRC, and there was no mention of the type of steel.

 

[John Turney]

There are all kinds of stainless steels; some softer, some harder, some magnetic, many not. Without knowing which ss is used, we can't tell.