it works better to have richer pilot jets for aggressive clutching and so forth, a 2 stroke needs fuel to accelerate the engine. You can enrichen the bottomend some with the fuel screws but i dont like to adjust them further out then 2 turns. Otherwise the chance is for them to fall out as the spring doesnt have alot of tension on them after that, some guys run them out further, i just try to stay around 1.5-1.75 and just use the richer pilot jet.
40's in a srx is "ok" but youll need the screws out a fair amount if you have aggressive clutching, or youll have a bog on take off. I generally use 45 on ported sleds. 42.5 work well in alot of clutched-set up trail sleds.
The other good thing is none of my sleds have idle hang as the mixture is richer and they drop right back instantly.