black rod bearings back side

made 3 hits on new combo
brad 5 with grp rods
010/010 crank
brad 100 tall forged block
4.467x 4.250
on a 2 step and it was rich
timing was 18 degrees (bad track???)
rod bearings on the back side look like
black film that if rubbed off on my finger
it looks like its polishing the aluminum rod
bearing looks good on crank surface
2 aborted passes and 1 4.26 @169
ive never seen this on my fuel head motor
thanks
duane

 

Are you sure you have .010 under bearings in the rods? How about the bearing tangs, are they going flat? Sounds like the bearings are fretting against the rods leaving the black residue.