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BrianG · 05.31.2006, 12:37 AM

After running it for a while, feel the slipper plate. If it is slipping a bit, it will be quite hot (be careful not to burn yourself like I did once!).

As to the rc speed calculator: the speed calculations were made based on the various gearing (which IS correct BTW), motor kv, battery voltage, and tire diameter. Factors such as weight, rolling resistance, drag, real battery voltage, and actual kv can have a significant impact on the real-world result, especially at higher speeds.

For instance, in the RCM store, the Wanderer motors there are listed with loaded kv values. However, if your model is quite light and you are running at top speed, maybe the actual kv approaches the unloaded value instead? Or the actual kv value of your motor may be slightly higher than specified. The battery voltages listed are based on 1.2v for NiMH/NiCD, and 3.7v for Lithiums. NiMHs can be higher, like 1.3v under a light load, and Lithiums can be higher as well. This can also make a difference.

There are so many factors to take into consideration that it is difficult to come up with something very accurate. Even in my experience, my Revo seems to go faster than I calculated. But, I can't simply add a "fudge factor" to compensate because of the vastly different vehicles and it would be inaccurate at best. Unfortunately, I realized all this after I finished it.

	(#20)
BrianG RC-Monster Admin Offline Posts: 14,609 Join Date: Nov 2005 Location: Des Moines, IA	05.31.2006, 12:37 AM After running it for a while, feel the slipper plate. If it is slipping a bit, it will be quite hot (be careful not to burn yourself like I did once!). As to the rc speed calculator: the speed calculations were made based on the various gearing (which IS correct BTW), motor kv, battery voltage, and tire diameter. Factors such as weight, rolling resistance, drag, real battery voltage, and actual kv can have a significant impact on the real-world result, especially at higher speeds. For instance, in the RCM store, the Wanderer motors there are listed with loaded kv values. However, if your model is quite light and you are running at top speed, maybe the actual kv approaches the unloaded value instead? Or the actual kv value of your motor may be slightly higher than specified. The battery voltages listed are based on 1.2v for NiMH/NiCD, and 3.7v for Lithiums. NiMHs can be higher, like 1.3v under a light load, and Lithiums can be higher as well. This can also make a difference. There are so many factors to take into consideration that it is difficult to come up with something very accurate. Even in my experience, my Revo seems to go faster than I calculated. But, I can't simply add a "fudge factor" to compensate because of the vastly different vehicles and it would be inaccurate at best. Unfortunately, I realized all this after I finished it.