After running my gilardoni pretty hard the other night, i noticed it was acting a little differently on my way to work tonight. i didnt rip on it hard tonight and when i got home, i pulled it apart and found all this stuff.
these two gouges on the piston line up directly with the intake port and the scuffing around it, that you can see here:
there are also a lot of these little scuff marks that you can see dabbling around in there with the cross hatching:
i already seized it pretty hard on the exhaust side and managed to clean all that up reasonably well but i have no idea what the deal is now. it almost looks like there was some debris in the cylinder or something. maybe i just need to chamfer the ports? i didnt do that when i got it because they didnt feel any worse than the ports on stock cylinders...i guess with the added RPMS i should have just done it anyway. the base gasket also had a leaky spot on it, maybe that contributed to it?
anyway, its running a 21mm PHBG, needle in the 2nd richest position with a 50 idle jet (which is way too rich) an 86 main jet (it 4 strokes pretty seriously with an 88 and an 87 is better if its a little chillier but its been warm lately), and one of those little black malossi air filters. the plug is a B8HS. I've been running at 40:1. the plug is black and kind of sooty.
thats the other thing, do you think i need to run at max 50:1 with synthetic a la the polini seize problem?
i dunno, i'm at a loss. help me out.