Does anyone know if the quiet Yosh Zyclone or Jardine street pipes are still available? Or where they ever?

Yes, they both are. I have a Parts Unlimited catalog which shows them both in it. It is in a .pdf format if you wanted to look at at.

I just picked up a set of Yoshi slip ons off of Ebay, and I have also seen the Jardines sell as well. If you don't want polished, link to sellers store on page, and you can probably find carbons.
A couple of links--

http://cgi.ebay.com/ebaymotors/ws/eBayISAP...0408&rd=1,1

http://cgi.ebay.com/ebaymotors/97-03-Honda...063385932QQrdZ1


Randy

These are pretty quiet from what I understand, right? Almost mistaken for stock in some cases?

um... I've got the Yosh RS3 with the ZYclone baffles, and they're a bit louder than my punched baffle stock cans, especially during low rpm cruise, or putting around, or WFO, but are about the same just cruising on the interstate...

Mike

I'ver got the Yosh RS3's and they are significantly louder than stock. They drone a bit at low speeds-have to wear earplugs. Not that loud to the outside world according to friends I ride with though.

I have Yoshi RS3 Zyclone centred ones, just slip-ons, that sound fairly quiet, they gave more power mid-range to top end. It easily pulls all the way to redline in top gear. I'm yet to put a good fuel/ignition map on to the Powercommander.
The Yoshi's are louder than stock, especially from 4000rpm on, but the benifits are good.