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Spitfire Driven Hubs Breaking?

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Spitfirejoe Avatar
Spitfirejoe Joe Guinan
Fremont, Nebraska, USA   USA
1980 Triumph Spitfire 1500 "The Phoenix"
Has anyone seen this happen before? The driven hub is cracked in a circle around the axle. A friend who is doing autocross events in his late Spitfire has had several similar failures. He is running Kumho autocross tires, sized195x55x14.

We think this might be related to using an air impact wrench in doing the R&R of the hubs. If anyone has other ideas, we'd certainly like to hear what they are.

Thanks in advance.



Joe Guinan
Fremont, Nebraska

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tapkaJohnD Avatar
tapkaJohnD John Davies
Lancaster, Lancashire, UK   GBR
Never seen this before - it's common to break the half shaft at the known stress point, where the diameter narrows.
Most UK racers will have had this happen to them - I got so fed up, I've converted to a Rotoflex style, with CV joints and Volvo half shafts, with MGF uprights and hub

If you don't want to/aren't allowed to do this major mod, then I'd treat it as competition wear and tear, and life your hubs, or else examine them closely (crack test?) every so often.
14" wheels won't help, either. You are having to use 55 profile tyres to fit them in the arches, so MUCH stiffer sidewalls than the radials first fitted to them, with 70 profile.

John

clshore Carter Shore
Beverly Hills, Florida, USA   USA
I've not seen that, but once you have addressed axle breakage as John described, it's just the next weakest link in the chain.
(Although I did see fatigue cracks in the center sections of the stock steel wheels we had racing rain tires mounted on).
Anyone know if this part was ever upgraded in production? (Rimmers show the same part# FAM2004 for Herald and GT6)
Consider the wheels and tires of the day when it was first designed.
Did the live rear axle Triumphs before Herald also use hubs bolted to axles, or were they 1 piece forgings?
(Rimmers show TR2-5 with hubs bolted to axles)



Edited 1 time(s). Last edit at 2015-07-12 09:43 AM by clshore.

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14GPDJENGINEERING Avatar
Silver Spring, MD, USA   USA
Standard 10 thru TR7 4 speed used the same style hub.

Rimmers shows UKC1343 for TR7 but NLA!

Dennis smiling smiley



Dennis smiling smiley

clshore Carter Shore
Beverly Hills, Florida, USA   USA
In reply to # 1302635 by 14GPDJENGINEERING Standard 10 thru TR7 4 speed used the same style hub.

Rimmers shows UKC1343 for TR7 but NLA!

Dennis smiling smiley

Yah, I wonder if the TR7 UKC1343 taper and key are compatible with Spitfire?
The TR7 5 speed shows a one piece axle RKC4632/4633, wonder if it's 4x3.75"

Spitfirejoe Avatar
Spitfirejoe Joe Guinan
Fremont, Nebraska, USA   USA
1980 Triumph Spitfire 1500 "The Phoenix"
[/quote]

Yah, I wonder if the TR7 UKC1343 taper and key are compatible with Spitfire?
The TR7 5 speed shows a one piece axle RKC4632/4633, wonder if it's 4x3.75"
[/quote]

Weren't all the wedge cars 4x3.75"? I have TR8 Wheels for the Spitfire race car. like many others I've seen.

That makes the axle you mentioned a little more interesting...



Joe Guinan
Fremont, Nebraska

clshore Carter Shore
Beverly Hills, Florida, USA   USA
Rimmers still has the TR-7 axles, only $35.18 (plus shipping!)

http://www.rimmerbros.co.uk/Item--i-RKC4632U

These could be the basis for an affordable 1 piece street car replacement for the Spitfire 2 piece axles.
Bearings would need to be identified, and the hub would need to be modified for them.
Replace the inside needle bearing with one having an inner & outer race to eliminate ruining the
axle when the bearing fails.
Axle needs to be shortened and machined for a UJ yoke, might be able to repurpose a stock one.
Any competent machine shop could handle these tasks.

Here's a link discussing the 1 piece racing axles.
I have a set of the racing SAE axles discussed:

http://www.triumphexp.com/phorum/read.php?22,1300896



Edited 2 time(s). Last edit at 2017-03-20 03:56 PM by clshore.

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