i have heard different stories regarding the rims/wheels of the rx8. the rx8 wheels have rf sensors in/on them for tire pressure radings and suspension (like the corvette). i do not know if all rx8 have them or just special pakages (gt or tr) but if you buy rims without the rf sensor it will screw up your reading. so yuo might want to check with your dealer BEFORE buying new wheels/rims/tires to see if they are compatable. again this is just rumors ive heard i can not confirm any of this until the car gets here and we can look at one for sure. if anybody else knows about this please post.....

to add more fuel to the fire... here is a related post:

http://www.rx8forum.com/showthread.php?s=&threadid=4776&highlight=sensor

Originally posted by ibfubar2000
i have heard different stories regarding the rims/wheels of the rx8. the rx8 wheels have rf sensors in/on them for tire pressure radings and suspension (like the corvette). i do not know if all rx8 have them or just special pakages (gt or tr) but if you buy rims without the rf sensor it will screw up your reading. so yuo might want to check with your dealer BEFORE buying new wheels/rims/tires to see if they are compatable. again this is just rumors ive heard i can not confirm any of this until the car gets here and we can look at one for sure. if anybody else knows about this please post.....

They are mounted inside the rim and can be swapped from rim to rim, or they are the indirect type that reads from the antilock sensor (nothing inside the wheel at all). Some care has to be taken when mounting a tire (get a reputable shop), but otherwise it's no real issue.

More information at:

http://www.tirerack.com/tires/tiretech/general/tirepressuremoni.htm

Eastmoon San, Did you swap the sensors to the new rims?

Since Mazda claims the system is RF it uses sensors mounted to the wheels. I have seen these and they are simply mounted with a strap around the wheel. Like a big hose clamp. I bet there are aftermarket straps available.

It has been said many times before that the RX-8 will be using the indirect type of sensor. This type uses the Antilock braking sensors to sense the rotational speed of each wheel. Changing your rims/wheels will be just fine. (even to different sizes, because it's the speed of rotation compared to the other wheels, not compared to a norm.)

Originally posted by IGOZMZM
It has been said many times before that the RX-8 will be using the indirect type of sensor.It may have been said, but it was speculation, and incorrect. According to Mazda's own Product Comparison Guide:Tire pressure monitoring system
• Uses a radio frequency to monitor wheel-mounted tire pressure sensors, activating a warning light in the instrument panel if the tire pressure is too lowAccording to the Tire Rack page somebody cited earlier, most OEM RF systems use a sensor that's integrated into the valve stem assembly, rather than strapped to the wheel with a band. That being the case, there's a slight possibility that the unit may not fit particular aftermarket rims, depending on the design in the proximity of the valve stem hole.

good thing I am getting mine custom forged!

I think I remember East Moon saying the J-spec and euro cars arnt getting tyre pressure sensors.

This is only a US thing because it'll soon be law in US.

Originally posted by Superfan
Eastmoon San, Did you swap the sensors to the new rims?

thanks RobDickinson Your memory is right.
I already wrote that.
My Japanese spec RX-8 is not have tire pressure sensor, from the first.

EAST MOON

Originally posted by RobDickinson
I think I remember East Moon saying the J-spec and euro cars arnt getting tyre pressure sensors.

This is only a US thing because it'll soon be law in US.

Just out of curiosity, why does the government think that it knows how to build cars? Most of the folks that we vote into congress wouldn't know a spark plug if someone threw one at them . . . not that I would do that. I'm just tired of buying legally required equipment that I have been driving without for most of my life, and have never felt the lack of. Side impact protection, OK I see the reason for that, but I have had catastrophic tire failure, and it was never that big a deal. I want this system like an extra hole in the head, or for instance daytime running lights, which were also legally required for a short time until people forced congress to unrequire them.

Sorry for the rant -

H