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MetalMan · 11.28.2006, 05:50 PM

The motors have a limit to how fast they can spin, and there's a point where the excessive rotation of the motor causes the efficiency to drop a lot. Castle says the RPM limit for the Mamba Max motors is 65,000 RPM. The 4600 on 4s Lipo is pushing that limit, as is the 5700 on 3s Lipo. Using the 7700 on 4s Lipo would result in a RPM of over 100,000 RPM, which would most likely kill the motor as soon as it got over 80,000. Even the 5700 on 4s Lipo would be spinning at about 80,000 RPM, which is way too much.
Exceeding the RPM limits would be likely to cause the rotor to slip off the shaft, cause the rotor to break apart ("grenade"), or get the rotor so hot that it is demagnetized.

The 4600 on 3s Lipo will get you to 40-45mph, if not to 50.

	(#18)
MetalMan RC-Monster Mod Offline Posts: 5,297 Join Date: Mar 2005 Location: SoCal	11.28.2006, 05:50 PM The motors have a limit to how fast they can spin, and there's a point where the excessive rotation of the motor causes the efficiency to drop a lot. Castle says the RPM limit for the Mamba Max motors is 65,000 RPM. The 4600 on 4s Lipo is pushing that limit, as is the 5700 on 3s Lipo. Using the 7700 on 4s Lipo would result in a RPM of over 100,000 RPM, which would most likely kill the motor as soon as it got over 80,000. Even the 5700 on 4s Lipo would be spinning at about 80,000 RPM, which is way too much. Exceeding the RPM limits would be likely to cause the rotor to slip off the shaft, cause the rotor to break apart ("grenade"), or get the rotor so hot that it is demagnetized. The 4600 on 3s Lipo will get you to 40-45mph, if not to 50. 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