for sp140, you need to replace the stock ratio gearsets... kaya yan ng stock gears pero hirap ang motor in the long run..
also your piston body kakayanin pero parang hindi tatagal... meron naman mga magandang piston body aside from deepfire titanium tooth.. and they come cheap way cheaper than deepfire titanium
yan ang pinakaimportanteng papalitan kung sp140 ikakabit mong spring...
but for sp130, ok naman kahit hindi mo palitan yan.. kakayanin naman ng matagal.. just avoid dry fire hehehehehe
very stiff na kasi ang sp140 for stock ratio gearset, kahit naka super duper torque motor ka eh mahihirapan yan heheheheh... and also napakalakas umubos ng charge ng battery kung sp140 and stock ratio gearset ka lang