Chlorinated brake cleaner probably would. I use a naptha-based brake & clutch cleaner from TPS which is very mild but which cuts through oil and grease very well indeed, although ironically it doesn't dissolve brake fluid
Its much easier on PF and FL1 though as they are lacquered in the engine bay and so quite robust. The FL2s aren't lacquered so you have to be very careful not to dissolve the paint! On those I use Gtechniq W7 tar remover as that is quite benign and remarkably powerful. I also have a product called 'Dirt Juice' bike cleaner from my neighbours which is also quite a mild solvent but in an aerosol so it has dirt-blasting power if needed.
Once the oil is gone I use Gtechniq W5 APC most of the time, in varying concentration depending on the level of grime. In this case, being the worst I've encountered so far, the W5 was mildly supercharged with 10% Autosmart G101 which is an extremely powerful alkaline APC - basically a trade version of the Elbow Grease product discussed in other threads. I'd be disinclined to put G101 anywhere near an FL2 engine bay though. Beware toluene-based tar remover as well as that also dissolves the unlacquered paint.
Once it's all clean-ish with no more grit or chunks I'll use a waterless wash or quick detailer to tidy up any smudges, and then a sealant to finish off.