need help with chain and sprockets

I have a 1979 KZ650. While I was putting it in the truck I noticed that my rear sprocket was very worn. I would like to replace the sprocket but I would also like to drop my gearing a little. I am guessing the bike has stock sprockets the rear is a 42 tooth and I don't know what the front is I am hoping somebody can point me in the right direction for gearing. I also wouldn't mind going to a heavier chain since the bike is destined for a turbo.

Any info will help Thanks
Killian

Jeff at Z1E will be able to get you the right setup, and you dont need a heavier chain, just get a good quality new 530 chain and it will be able to take just about anything you can throw at it, chains have come a long way. If the new big ZX's can use a 530 chain, I'm sure a turbo KZ650 wont hurt one.
Scott

Post edited by: 77KZ650, at: 2006/04/18 22:51

My nephew's 79 KZ650SR had 16 front 42 rear, so it sounds like yours is probably the same.
He now has 18 front 45 rear, but it now has a GPz750 motor in it (and swears that he will be riding it before the month is over).