YZF600R barrels, pistons, use with FZR head, and bottom end

[STN]

Can you use a yzf600r's barrels, and pistons and conrods, and use the fzr head and bottom end?

[cad600]

You want the YZF600 head. You also need some other parts, but it creates a 661cc engine (commonly called the 660).

[STN]

Yeah, but aren't the heads almost the same? They use the same bolt pattern, and the valves are roughly the same size, and the cams are the exact same. Has anyone ever attempted to just use the barrels, conrods, and pistons?

[cad600]

The YZF600 head has slightly better flow characteristics. Will the FZR head bolt on - yes. But the YZF600 head will better optimize the setup.

[STN]

Ah, that it would, but by how much? If I use the YZF head then I'll need the yzf carbs, which shamefacedly are the only bits for the 660 I dont have. How much of a difference would it make if I stuck to stock head and fzr carbs. I'm going for cheap horsepower. Although I could get the carbs for 50 bucks...

[cad600]

32mm Mikuni carbs for the FZR600 vs. 36mm Keihin carbs for the YZF600. To me, the Keihin carbs are easier to work on but that is a personal preference.

[Cursed94FZR600]

does anyone know if the YZF had 32mm carbs at one point and later in production they changed over to 36mm? if they did, do you know when they made the change?

[cad600]

PM'ed you back on this.