Hey just wondering if anyone knows the stock throttle cable thread size  for a 1998 savage. I got the performance mikuni from lancer and I know he gets three different throttle cables from barnett depending on year of bike. I'm wanting to put a custom throttle housing on and the thread size for it is 5/16-18.

Most likely you will need to have a custom cable made if you are going to start changing things around.

The Mikuni needs a different throttle end than the stock CV carb, and the throttle control end is not threaded at all - it is a slip fit with a tab and screw to hold it into place.

If you are going to install a different throttle control...you will need to have a cable made (or make one) to fit whatever you choose to use.

http://www.ebay.com/itm/99-Suzuki-Savage-LS-650-Good-Throttle-Cable-FastFreeS...

You can get all the parts, cables, fittings, sleeves, etc. that you need to build your own cables from these folks.  You just need to know how to solder on steel well...you need a different flux than you use on copper pipe.
http://www.venhillusa.com/