Hey pol,
as littlebear said, I ordered the 3.6kg JUN flywheel from <a href="
http://www.perfectrun.com.au">PerfectRun.com.au</a>. They were pretty good with their pricing, postage and service, very quick with replying to emails etc. It seems that they are simply a middle man in that they do not have the items in stock. In this way, prices for the items and the postage vary with the exchange rate.
It worked out that the flywheel cost me around AU$390, postage was around AU$80. It arrived within 6 days, Japan to Adelaide.
It really is a great mod. Some people make the comment that you will have problems with the lack of engine inertia to help keep idle or to prevent stalling when launching when installing somthing so light. But I have not had this trouble, it is great. So much better engine response, the micra just wants to rev and get the car going. I guess the only problem is now that I am wanting to race everything, so for the moment fuel economy is probably not the best until the novelty wears off. I'll need to do a couple of test runs agains my sister in her stock standard LX.
Here are a couple comparison photos. As you can see, if you were going to try and lighten the factory flywheel, you've got a lot of work to do...
Standard (I think 8.6kg) Flywheel:
<img src="
http://w7er8q.bay.livefilestore.com...hTIwGI2SdrPrfc1fifAvT3Zo-T9IbaXI0ObIkqv4JXmeU" width="640" height="480">[/img]
<img src="
http://w7er8q.bay.livefilestore.com...uhItFuZjbe4B3fe7Ke-NIZ3dyXonAJylhHi6ikM0Uh3HI" width="640" height="480">[/img]
JUN 3.6kg Ultra-Lightweight Flywheel:
<img src="
http://wdyetg.bay.livefilestore.com...7NfcNFhEoPH4jDlmAKS2UfBbqwzFKUkPiUq9rQulHkbsk" width="640" height="480">[/img]
<img src="
http://wdyetg.bay.livefilestore.com...Iw6Es68aklDvF5lr29ZohCzkqUD3zUMA-sYO_x7KOo6Mo" width="640" height="480">[/img]
As an example, <a href="
http://www.cypherindustries.com.au/products.php?cat=drivetrain" target="_blank">these guys</a> recon that the difference in acceleration experienced in 1st gear for every 1kg removed from the flywheel is like removing 30kg from the weight of the car.
SO the Ultra-Lightweight JUN item is 5kgs lighter than standard, and is supposedly like taking your stock standard 850kg micra down to 700kgs. I really do not know how much truth there is to this, but it'd be interesting to be able to test it.