Pingel

Measure the center-to-center bolt hole spacing. An easy way is to measure from the left or right edge of each holt hole. not that it's really necessary since most of them are either 34mm or 44mm .... 44mm = 1.73" .... so almost 1-3/4" 

That inexpensive petcock is probably made in china. no thanks.
I don't know if there are any oem shaped manual fuel valves that will fit.  Yamaha raptor/grizzlys have manual fuel valves but I think they're 34mm. these are reasonably priced which is why I mentioned them. maybe you can find one from Yamaha that will fit your KZ650.

martin_csr wrote:

Measure the center-to-center bolt hole spacing. An easy way is to measure from the left or right edge of each holt hole. not that it's really necessary since most of them are either 34mm or 44mm .... 44mm = 1.73" .... so almost 1-3/4" 

That inexpensive petcock is probably made in china. no thanks.
I don't know if there are any oem shaped manual fuel valves that will fit.  Yamaha raptor/grizzlys have manual fuel valves but I think they're 34mm. these are reasonably priced which is why I mentioned them. maybe you can find one from Yamaha that will fit your KZ650.
 

Thanks. Just measured again. From center of bolt to center its about 1-3/4 so its 44. Thanks for this!