Originally Posted by
zipper
We recently had some guys turn up at our track that were running 540 brushless setups in there Mini's and then was told that the track owner will allow 540 brushless motors to be run in the next season. It is a $200 upgrade that most of the Mini guys at our track can’t justify spending on a Mini.
What are your thoughts on running 540 brushless motors in the Mini class?
We just finished up the 2008 Novak Touring Car Championship race, and we ran 17.5 brushless motors for the mini class. It was fantastic for many reasons. First, no need to buy/collect 6 or more silver cans looking for a "good" one. Second, everyone had the same top speed, and the ability to have the same infield pull power (differential building techniques really showed up here). Third, absolutely no maintenance. Motor temp after a full race - about 80 degrees F.
We were going to run silver cans for this race, with a blind motor draw like we did for Mini Mayhem, which helped to equalize power/speed. Novak wanted to run an "all brushless" race, so we tried the 17.5's beforehand and found that they were almost identical in lap times to a silver can on our 100' x 50 ' carpet layout. Excellent silver cans have more top speed in this gear limited class, but brushless have more infield power, so it basically made them equal overall. At a track like Tamiya USA's Aliso Viejo track, the difference would give an advantage to a silver can (due to the very long straight/sweeper), but on your more typical track with 100 foot or shorter straight, they are pretty equal overall.
Only downside to the brushless: initial cost and ESC size/weight. We were able to use free "loaner" 17.5's and Novak XBR esc's for this class, courtesy of Novak (thanks Bob Novak and Charlie S.) for the weekend, and were able to buy them after the event for only $170. A brushless esc and motor definitely weighs more than a silver can and very small esc (like at GTX), and the footprint of a brushless ESC is so much bigger than a GTX that it is very difficult to put the brushless ESC anywhere other than on top of the chassis just behind the servo. (I mount my GTX low in the rear pod of an M-03 to keep the center of gravity low). Mounting the XBR on top of the chassis raises the center of gravity, which with high grip carpet situations, induces the possibility of traction rolls.
I'm hoping that Tamiya USA adopts 17.5's for the TCS mini class soon.