Are Zippy Lipos safe with a Castle MMM Speedy?

[Finnster]

Yeah, the only time I would consider going up in the gear is by also going to much smaller tires and using for speed runs on street only. With the lighter tires and lower rollout, the motor load may actually drop. No way to know w/o testing, but I'd start with the lighter tires and smaller gearing and work my way up from there.