Hi, all- Apologies if you saw my other thread on this in another forum; erased it now that I have more info. Could use some insight from the collective, for sure. Got my G15-CS assembled, started, and run slowly around the block, but found the bike very sluggish and the RH cylinder was running very cool. Pipe was only warm to touch, and the pressure out the exhaust was noticeably less than the LH. Edit: There was also an occasional pop/snap out the RH pipe at idle, which I attributed to unburnt fuel igniting in the pipe, based on the apparent rich condition. LH plug had clean insulator and sooty ring around the outside. RH plug (cool cylinder) was wet, with dark insulator. I swapped the plugs; RH cylinder remained the cool one. I pulled the carbs off. (Monobloc 389, linked by balance tube, RH with the short bowl.) Found nothing unusual in either, or in the balance tube. First time with Amals of any kind, though, so maybe there is something I don't get. Jet blocks are appropriately tight and the gaskets are in place, so I don't think they're the source of any undue richness. All new gaskets, jets, and needles following a re-sleeving. I am currently waiting on the improved brass/viton float needle before reassembling. Float height seemed a bit low so I have put one gasket under the needle seat. Valve lash checked cold, .006 all around. Compression test (cheap Harbor Freight model) dry showed 90 both sides. With a little oil on the rings it was 100 on the LH and 110 on the RH. Kind of a relief to see there wasn't a huge variance between them, even if the tester is somewhat inaccurate overall. Guessing timing could be the only explanation at this point?? If the timing was just off in general, could it cause this left/right discrepancy? Or is it more likely linked to a poorly-made, uneven ring cam on the mag? Any ideas on how to proceed would be much appreciated.