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Hi All,

I need some help ID'ing these wheels. I believe they are genuine Watanabe's - unsure of the material, but they are very very light. They are 14x6.5.





Thanks all,

Earlysport

You'll find Japanese stamps on them if they are Japanese. Pretty sure I see a RBF stamp on it which is a good sign pointing towards Watanabes.

They sure are.

See that circle with 3 symbols in it? That's the RS Watanabe stamp with the 3 falcons in it. It's on the face of every watanabe wheel and centre cap.



Also those are Watanabe F8 wheels in 14x6.5 +36 from memory. They will be cast alloy but watanabe did make magnesium wheels too (though not in F8/F8F style from memory, only A-B faces)

I think the stamp on the rear suggests that they are 14x6 Watanabes and from the yellow staining my guess is they are the magnesium 8 spoke street mag wheel.

Think the magnesium Wats had 'mg' on them. Check them carefully as the magnesium Wats can be fragile.

The Aluminium f8 Wats weigh 5.1kg for the 14x6 and 5.5kg for the 14x6.5, the Magnesium are 3.6kg for the 14x6 and 3.8kg for the 14x6.5 if you want to try to weigh them to check the material.

throw them onto a fire until nice and hot, then spray them with water.
if they're magnesium it will be quite obvious.

hks_kansei wrote:throw them onto a fire until nice and hot, then spray them with water.
if they're magnesium it will be quite obvious.

OP, please don't do this. I assume you wouldn't, but just in case, don't.

I weighed one of the wheels, complete with the 185/60 14 tyre fitted.

Looking up tyre weights it seems a typical 185/60 1`45 is around 18lbs, or 8.18kgs.

The wheel and tyre I weighed at 12.15kgs, so that would put wheel weight at 3.97kgs.Of course I'd have to weigh it alone to determine the exact tyre weight. They're synergy m3 brand tyres.

So maybe they are the mag versions? I'd like to have a definitive way of knowing and will look closer for any other markings.

I'm going to clean them up and will probably sell them, as I'll run 15's on the circuit build I'm preparing for.

Cheers all for the information so far.

Earlysport

I weighed one of the wheels, complete with the 185/60 14 tyre fitted.

Looking up tyre weights it seems a typical 185/60 1`45 is around 18lbs, or 8.18kgs.

The wheel and tyre I weighed at 12.15kgs, so that would put wheel weight at 3.97kgs.Of course I'd have to weigh it alone to determine the exact tyre weight. They're synergy m3 brand tyres.

So maybe they are the mag versions? I'd like to have a definitive way of knowing and will look closer for any other markings.

I'm going to clean them up and will probably sell them, as I'll run 15's on the circuit build I'm preparing for.

Cheers all for the information so far.

Earlysport

I was given to believe the Magnesium ones had a Mg cast into them.


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I thought magnesium wheels had a limited life before failure?

As do aluminium wheels.


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bruce wrote:I thought magnesium wheels had a limited life before failure?

sailaholic wrote:As do aluminium wheels. Sent from my iPhone using Tapatalk

Arguably, the only material with an unlimited life is steel, and then only when the stress within the steel is kept below the 'endurance limit' (which is the maximum stress at which the life, measured in cycles, is infinite).

Having said that, some aluminium alloys have lives above 10 million cycles if the maximum stress is kept reasonable, and in fact the 's-n curves' can appear to stretch to infinity (similar to steel) as data doesn't exist for very high cycle counts. So, this may equate, say, to cornering at maximum lateral force for over 10 million revolutions of the wheel, which is approximately 20 million meters; or 20 000km of constant flat out cornering to produce maximum stress on the wheel. Some Magnesium alloys may be similar.

For the record, my final year thesis to obtain my Mechanical Engineering degree involved analysing, designing and building some wheels for a competition car (which were made from machined aluminium). If I'd had the ability to cast Magnesium at the time, I would have used that for the centres.

I always thought the issue was more that steel and to a lesser extent aluminium bend and stretch to a degree as they fatigue and reach failure.
Where magnesium more just cracks.

Of course, neither are really what you want, but a spoke cracking and snapping from the wheel is likely to be a lot more dramatic than one simply buckling.