Ok - I know the kit you're talking about. Are you buying from
www.classiccycleparts.com or somewhere else? It should cost you no more than $120 for the kit + shipping (a day ago they were selling for $100, but they raised the prices).
I just ordered the 555cc kit for my 550. I'm doing a 0.50mm overbore, which this kit equates to. 59mm pistons.
I think the 605cc kit has 61mm pistons. This obviously equates to a 2.5mm overbore. That's pretty high - about the maximum.
I'm paying $100 shipped for my 555cc kit. They're selling now for $100 + shipping. No sleeves in the 555cc kit, but really, you don't need them in a 550 bike and they'll cost a ton to put into your cylinder block.
Bottom line, if you're rebuilding the top end, the minimum is a new set of rings and honing the cylinders. Honda rings will cost you $100 for the set, and honing will run you $10-$20 per cylinder (guessing US prices - it was CAD$20 per here). Total cost = $180 or so.
For a bore, you can buy this aftermarket kit (Honda Canada says the o/s pistons/rings are discontinued - I didn't have an option or I would have spent the extra $ on Honda parts) for $120 and then boring should be about $40-$50 per cylinder. I'm paying CAD$60 each. Total cost = $320 or so.
What's the condition / size of the cylinders and pistons? If you can get away with rings and honing, I'd stick with that. I'd rather have original pistons in my bike. But, if the cylinders are on the borderline, then go ahead and bore. Everything is brand-new, you get to break your engine in, and you know what you're sitting on.
While you're in there, replace the cam guide, cam slipper and cam chain as well. Another $100 in parts.
Cylinder Diameters
Overbore CB500 CB550
0.00 55.98 58.48
0.25 56.23 58.73
0.50 56.48 58.98
0.75 56.73 59.23
1.00 56.98 59.48
1.25 57.23 59.73
1.50 57.48 59.98
1.75 57.73 60.23
2.00 57.98 60.48
2.25 58.23 60.73
2.50 58.48 60.98
2.75 58.73 61.23
3.00 58.98 61.48
