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MetalMan · 01:44 AM

This is a very intriguing idea... I've already got an old mountain bike with 24" wheels and a rear derailleur and without pedals, an OEM RC Sentilon 12s Lipo 100amp ESC, an Astroflight servo tester, 4 x 12v 7Ah lead acid batteries, and 2 x 5s2p A123 packs + an extra 1s2p. If I could get that gigantic outrunner from United Hobbies that sike linked to, a suitable chain-drive "pinion gear" from http://www.spd-si.com , and mount everything, then I'd have a fully functional electric bike... Now onto Brian's calculator to figure out what size "pinion gear" I would need to achieve 30mph.

EDIT: The motor sike linked to is 180kv. Based on calculating gear ratios, it would require a reduction of 22:1 to run at 30mph tops with 26" tall tires and 48v. I did find that they have a 130 kv version of the same motor:
http://www.unitedhobbies.com/UNITEDH...idProduct=5142
With the same tires it requires only a 16:1 reduction.

	(#5)
MetalMan RC-Monster Mod Offline Posts: 5,297 Join Date: Mar 2005 Location: SoCal	01.20.2008, 01:16 AM This is a very intriguing idea... I've already got an old mountain bike with 24" wheels and a rear derailleur and without pedals, an OEM RC Sentilon 12s Lipo 100amp ESC, an Astroflight servo tester, 4 x 12v 7Ah lead acid batteries, and 2 x 5s2p A123 packs + an extra 1s2p. If I could get that gigantic outrunner from United Hobbies that sike linked to, a suitable chain-drive "pinion gear" from http://www.spd-si.com , and mount everything, then I'd have a fully functional electric bike... Now onto Brian's calculator to figure out what size "pinion gear" I would need to achieve 30mph. EDIT: The motor sike linked to is 180kv. Based on calculating gear ratios, it would require a reduction of 22:1 to run at 30mph tops with 26" tall tires and 48v. I did find that they have a 130 kv version of the same motor: http://www.unitedhobbies.com/UNITEDH...idProduct=5142 With the same tires it requires only a 16:1 reduction. SH Z-Car, Custom Crawler, 8s Savage, 12s XTM XLB 1/7 buggy, 4wd 4-link rear/IFS Pro4 truck, Custom Hyper 10 Short Course, Belt-Drive Mammoth ST 1/8 truggy, 4s 17.5 MM Pro HPI Blitz Last edited by MetalMan; 01.20.2008 at 01:44 AM.