The LiPo does not have the cutoff, some ESC's (Electronic Speed Control) have an auto cutoff programmed for LiPo batteries. Again, going to a LiPo with the sotck radio equip. is a risk, you could fry everything. Try looking for a 6v NiMh battery that maybe has a little more capacity or mah. The weight difference should be next to nothing if you stic with the same amount of cells as the original battery. Just going to a brand name of the same battery would make a difference. The stock batteries are just about worthless.