Wheel weighs

A question that’s come up a few times, so whilst swapping them over today, I weighed my wheels.

17.2kgs = Front Rimstock (orig wheel) with Yoko A039
14.8kgs = Front Speedline with Yoko A048

2.4kgs = Difference/saving


19.8kgs = Rear Rimstock with Yoko A039
18.2kgs = Rear Speedline with Yoko A048

1.6kgs = Difference/saving


Lugging them about, the Speedline felt much blooming lighter though!

I didn’t have a spare tyre(s) to hand, otherwise I’d have weighed that too.

Ian

Hmmmm, Ian, but the A039’s are lighter than the 48’s.

Also, were they more or less worn the same?

I know, we could have weighed them alone when we got them, but somehow it didn’t happen.
We’re a lazy bunch

Same amount of wear. I’ll try weighing the tyres at some point, I have old ones of each.

Ian

I’ve just weighed a 39 and 48 front, same trye wear on each, both came in at 7.8kg, a worn 39 rear was 8.6kg and a new one was 9.8kg

Ian, please weigh the wheels without the tyres to end all the guessing over the years

So 39’s are not lighter than 48’s

And Speedlines are not THAT light?

A question that’s come up a few times, so whilst swapping them over today, I weighed my wheels.

17.2kgs = Front Rimstock (orig wheel) with Yoko A039

@8.5kg = front rimstock without any tyre (but about 100grams of wheel weights & a rubber valve!)


19.8kgs = Rear Rimstock with Yoko A039

@11kg = rear rimstock without any tyre (but about 20grams of wheel weights & a rubber valve!)

both were weighed with a Salter spring balance rather than the bathroom scales!

AO39 tyres only:

6.8kg = front down to wear indicators

8.9kg = rear down to wear indicators

AO48 tyres only:

9kg = rear down to below wear indicators (near slick)

17.2kgs = Front Rimstock (orig wheel) with Yoko A039
19.8kgs = Rear Rimstock with Yoko A039

15.3kg = Front Rimstock (orig wheel) with Yoko A039
19.9kg = Rear Rimstock with Yoko A039

I get the impression we’ll never get anywhere near the truth…

Hmm, I would suggest shopping trolley wheels, I belive they weigh very little, run flat tyres as well come as standard.
I would love another set of wheels, I had a set of speedlines on order for months when they were supposed to have been 3 or 4 weeks.
I couldnt be bothered to buy them in the end as they couldnt be bothered to contact me and tell me they were going to be late.
Im now probably going to buy some compomotive MO’s to put some road tyres on and take off the standard alloys with my 48’s on for the winter and to save for some trackdays next year.
I belive the compomotive’s weigh more than standard but to be honest i dont care im too busy driving it to bother setting it on some scales.
Just got the new EVO Mag with their supposed write up of the tuner GP, which is rubbish, they will be getting a letter from me.
My car weighed the most out of all the lotuses there yet still managed very well.
Anyway off to get me some trolley wheels, hopefully ones that dont pull to the left all the time.

Christian

But there are so many truths.

Which one do you want?

I get the impression we’ll never get anywhere near the truth…

Uldis - to be fair we are not that far apart with regard to the weights for the rears with AO39s. Certainly within a combined manufacturing tolerance together with inaccuracies in our scales.

There just appears to be a discrepancy in the weight of the front Rimstocks…i have put everything away now so dont really want to remeasure but if Ian confirms his figs as correct then I’ll re-do mine…not that I’m saying he is wrong!

SteveJ, I keep meaning (and forgetting) to tell you. Your wheels are not the original Exige ones. They’re actually Lotus Motorsport ones. I believe the fronts are the same, but the rears have a slightly different offset. In theory, you’re supposed to use thicker brake discs or spacers with them, but I never had any problems. Shouldn’t be an issue but I thought you should know. I had to sign a disclaimer saying they were intended for track use only etc.

In theory, you’re supposed to use thicker brake discs or spacers with them, but I never had any problems.

Are you sure? Can’t quite see why a different offset would have any effect upon the brake disk thickness - isn’t that a factor of the caliper, ie distance between the pistons excluding pad thickness?

Sorry, I was talking about the thickness of the bell, not the actual disc area. The motorsport wheels are designed to be used with the motorsport discs.

The motorsport has ali bells - so they would be thicker to make a spacer redundent …

still lost a little on this…

I can understand the Motorsport wheels having a larger offset, ie, a wider track, if the Motorsport calipers would foul the standard wheels. However, I thought that the Motorsport wheels had less of an offset, ie, a slightly narrower track. I had assumed that this was an additional effort to try and reduce the stresses on the wheel bearings which were failing too regularly early on in the Motorsport programme?

I have a set of Motorsport wheels so could check the offsets if anyone wants the actual figures…

Steve I think the problem is with less offset the tyre can touch the chasis when under max corning force …

Could be wrong though …

I certainly noticed more touching of the wheel liners after using the Motorsport wheels…but they were fitted with slicks so your explanation might be right.