John in CR
100 TW
You can't run 30kw at 20s without running into heat issues. Heat is the enemy and it compounds, since the resistance of copper goes up by 0.4% per degree C of temperature increase.
Heat is difficult and slow to disperse to the environment, so the one best solution in the battle against heat is to create as little as possible. Steveo runs 400A combined from his controllers and surpasses 100°C with a couple of hard pulls of the throttle. Hillsofvalp did the same thing. At 400A you're creating over 5kw of heat with a cool room temperature motor, and almost 7kw of heat with a 110°C HubMonster. When you can shed maybe 1kw of heat continuously with a stock motor, it's easy to see how heat problems are such a problem for every forum member pushing performance. With winding heat going up by the square of current, heat created decreases much faster than performance as you lower current.
While HubMonster has a lower phase-to-phase resistance than other motors, which makes it better able to handle high current, there's still a finite limit. OTOH HubMonster has such a well designed and constructed iron core and slot and pole combination, that going to higher power via higher voltage costs only hundreds of watts of heat, not thousands of watts like pushing current creates.
I may sound like a broken record about this topic, but going up on current without appreciating the true consequences is a widespread mistake that's easily avoided, especially with HubMonster in a mid-drive since it's rpm limit is way way above the reach of even a 150V controller.
Heat is difficult and slow to disperse to the environment, so the one best solution in the battle against heat is to create as little as possible. Steveo runs 400A combined from his controllers and surpasses 100°C with a couple of hard pulls of the throttle. Hillsofvalp did the same thing. At 400A you're creating over 5kw of heat with a cool room temperature motor, and almost 7kw of heat with a 110°C HubMonster. When you can shed maybe 1kw of heat continuously with a stock motor, it's easy to see how heat problems are such a problem for every forum member pushing performance. With winding heat going up by the square of current, heat created decreases much faster than performance as you lower current.
While HubMonster has a lower phase-to-phase resistance than other motors, which makes it better able to handle high current, there's still a finite limit. OTOH HubMonster has such a well designed and constructed iron core and slot and pole combination, that going to higher power via higher voltage costs only hundreds of watts of heat, not thousands of watts like pushing current creates.
I may sound like a broken record about this topic, but going up on current without appreciating the true consequences is a widespread mistake that's easily avoided, especially with HubMonster in a mid-drive since it's rpm limit is way way above the reach of even a 150V controller.