larger pistons

Been reading do GPZ750 pistons fit 1300 giving it 1457cc 62mm to 66mm do the liners need changing??

Yes, the cylinder liners would need to be changed. You can bore the stock liners to fit 64 mm pistons and get away with it. The liner at the bottom gets really thin and many who have done the 64mm over have questioned the thickness although there have been no reports of cracked/ broken liners. 
It is a major change if you have the resources. Machining the cylinder block, custom sleeves ,custom head gasket and machining the upper half of the crankcase ( probably).
The pistons from the KZ 750 will fit nicely. They are heavier by 5 grams. Crown height, valve pockets and wrist pins are identical. Only difference as near as I can tell is the diameter. I bought a set off of EBay and have a spare cylinder block so for shits and giggles when I get a chance, I'll  machine up the required parts and have a go . It has been done by one of our members in Africa a while back. Sounded like a fun project for me since I also have a machining background.
Cosmetic for the head gasket. They make all kinds of gaskets for the Automotive racing circuit.
When I get a chance, I want to heat up the cylinder block to 250 - 300 F and knock out the liners and take some measurements, then ask L.A. Sleeve for a quote for custom liners. We'll  see where this goes.

Thank you, I would like to fit the 69mm pistons from the 750 turbo if I can as I have these on the shelf.

Kawboy wrote:

When I get a chance, I want to heat up the cylinder block to 250 - 300 F and knock out the liners and take some measurements, then ask L.A. Sleeve for a quote for custom liners. We'll  see where this goes.

• So I called LA Sleeve, who made a liner for Ray Slocomb after the upside-down ring was found that scored the cylinder wall.l.
• Spoke with ‘Dave’. He remembered and actually found the work order from the sleeve Ray purchased. The breakdown is this:
• $160 per sleeve
• $225 labor per sleeve
• Up to 3 months to make them
• Doing the math, (225+160) * 6 equals a staggering $2,310
  
  From CandyButt.Org