Hi

I seem to remember from a different thread that Chris Burke in Australia has all the HRC jets available individually. He has a bike shop and advertises on NSR World and on ebay.

For information on JHA vs HRC kits, both types are advertised for sale at the moment on Yahoo Japan. It's a hassle searching only by pictures and the odd word recognised by the Japanese search feature, but you can find it if you try. Infact here it is done for you. Try these links (first 2 HRC, 3rd is JHA):

http://page16.auctions.yahoo.co.jp/jp/auction/u26506617
http://page.auctions.yahoo.co.jp/jp/auction/113832761
http://page8.auctions.yahoo.co.jp/jp/auction/h66066201

Hope that helps.

NB. Read Andy's helpful jetting info on the tuning section as well, it will answer most of your questions.

Thanks

Dan