Hey guys! I started reading this forum a week ago and you've already answered about a hundred of my questions, helped me choose which scooter to go with and everything. I'm buying a new Razor Ecosmart Metro, and I plan on upgrading it in stages. If you could answer these few questions, I'll be well on my way to finishing the first! So, I have a long uphill on my commute home from work, and I want to increase the range so I don't blast up the hill and then have to crawl home for the last 2 miles. There are medium ups and downs all over my area, so I want to be able to get as much range as I can in general. I want to wire a second battery pack, as discussed here: https://support.electricscooterparts.com/support/discussions/topics/1000079185 but with some changes: First, I want to mount the batteries behind the seat instead of on top of the existing pack. Should I wire them with an on/off switch, as backups, or wire them all together? (I want to avoid getting a new controller and throttle etc, for the time being) If you could help me understand the pros and cons there, that would be huge! (My gut says go with the switch.) Second, to limit costs I'm sticking with 8ah batteries (Item # BAT-12V8AX3) instead of going up to 9ah, but I'd like to hear your thoughts. I figure I'll be essentially doubling my range if I add a backup pack with a switch anyway, and it makes sense to buy 3 new batteries instead of 6, since I plan on going with li-ion eventually. My only other question is about torque. I plan on upgrading to a 750 or 1000w motor in the future, but for now I wonder if you can guide me through choosing a different sprocket to gear the 500w motor for better hill climbing? Top speed isn't the priority here, as long as I'm not crawling along I'll be happy. This is my first scooter project, and it's been a blast scrolling through this forum and your parts website doing my research. You guys are great! Thanks for the help
Since most electric scooters have a 30 minute or longer range the 30 Minute Maximum Discharge Current row of the chart should be used to determine what size batteries to use.
For better hill climbing changing the rear wheel sprocket provides the most options. The Razor EcoSmart scooters original wheel sprocket has 65 teeth. 80 and 89 teeth sprockets that bolt directly onto the EcoSmart's freewheel sprocket are available. The large the wheel sprocket is the better the scooter will be at hill climbing.
The EcoSmart scooters top speed with its stock 65 tooth wheel sprocket is around 18 MPH. With an 80 tooth wheel sprocket the top speed would be around 15 MPH, and with an 89 tooth wheel sprocket the top speed would be around 13 MPH.