Keep my '82 GPZ750, or replace it with a YZF-600r?

[Juan1]

Here is a pic of an '82 GPZ750 in good condition:http://www.motorcycleclassics.com/classic-japanese-motorcycles/1982-kawasaki-gpz-750.aspx

Mine is in good condition except for the paint and a few bits of rust.  80 HP at the motor, plenty of torque, 1/4 mile times in the 12 second range, an upright seating position, a classic look, and it is easy to work on.  The downside is the 520+ pound wet weight, and it lacks the top end hit of modern 4 cylinder engines.

Here's the YZF-600: http://www.topspeed.com/motorcycles/motorcycle-reviews/yamaha/2006-yamaha-yzf-600r-ar3195.html

It would have a better engine, a 6th gear, better frame, better suspension, and better tire options.  It also looks relatively lame and has worse ergos...until the helibars and lower pegs are installed. 

So what would you choose?

[SAFE-T]

Well, the YZF600R2 (Thundercat) kicked butt in World Supersport racing in its day, so it's definitely got more potential than your '82 GpZ. On the upside the R2 had decent suspension, a fairly vibration-free motor and the monoblock calipers that Yamaha first used as OEM stoppers on the R1. And Yamaha continued to make it for a few years so there's decent aftermarket support for it except for high-end performance parts ~ if you are looking for an Ohlins rear shock you may be out of luck.

I think you would get used to the bars after about a month. If you still needed more legroom go ahead and get the lower footpegs. Overall, I'd say it was a relatively underappreciated bike that would make a great middleweight supersport-tourer