I need someone to help me determine what color or size rod bearings I need to order. I’m installing aftermarket rods big end bore is 39.5mm on all rods and crankshaft letters are BAAB 2011 cbr1000rr any and all help greatly appreciated o

 

This from the service manual - you need a more exact measurement of your rod size - unless it literally is 39.500mm exactly?

 

I havnt measured myself but that is what the box says. 39.5mm


 

You'll need to measure them then - the bearing caps are a few hundredths of a mm different.

 

Those tiny differences can be tricky. Hope you figure it out soon.

 

The aftermarket rods being labeled “39.5 mm” is only the nominal big-end bore size, and unfortunately that alone is not enough to determine the correct Honda rod bearing color. On these engines the bearing selection depends on both the crank journal code letters (your BAAB markings) and the actual measured rod big-end size, because the TBS bearings are graded in extremely small increments. You really need to measure each assembled rod bore with the caps torqued to spec and compare that against the crank journal sizes from the service manual, then verify final oil clearance with plastigage or bore gauge measurements. With thrust bearings this tight, even a few microns matter, so guessing based only on the box label can easily leave the clearances too tight or too loose.