R/C Tech Forums

Go Back   R/C Tech Forums > General Forums > Electric On-Road

Reply
 
Thread Tools Search this Thread
Old 11-30-2011, 11:30 PM   #76
Tech Elite
 
DesertRat's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2011
Location: Sniffin the 'Sauce Fumes
Posts: 2,705
Trader Rating: 2 (100%+)
Default

Be warned, taking boost away won't limit money, it will only limit top speed. Here in Arizona we have a few sponsored guys who run spec motor buggy (the only class with enough people to justify this sort of thing) and at our state championship the guys who were Novak motor racers were running huge rotors in their cars for more torque. You could tell it was them because if you pushed the car on a table the motor jerked like an old brushed setup. I am pretty sure they are also starting to hand-wind stators. Not to mention the newly minted 120C batteries. People are going to find ways to bend the rules, I think its eventually going to be locked endbell timing, and testing the motor itself for internal resistance. Or not, and we will just have the equivalent of the brushed days where the factory guys would show up and run stock with motors that blew your doors off but were technically legal.
__________________
I race toy cars for fun. If I need to explain, you'll never understand.
Current rides: Diggity DC4 Chassis #10. Losi JRX-S Type R. Losi 22 4.0, CRC Xi (retired), CRC Altered Ego Aluminum Chassis. Associated B4 based dirt oval late model.
WTB: Carpet racing in Arizona.
DesertRat is offline   Reply With Quote
Old 12-01-2011, 03:46 PM   #77
Tech Champion
 
robk's Avatar
 
Join Date: Aug 2001
Location: Macho Business Donkey Wrestler
Posts: 7,585
Trader Rating: 22 (100%+)
Default

120c batteries are useless if you draw 15A average. 120c on a 5000mAh pack is 600A, which you need about 500,000 MCM cable to handle. 10Ga AWG does not cut it. The stators are already handwound on Novaks...


Also....
"8.8.4.4.2 ROAR Spec Motors: External shaft diameter must be 0.125 inches (3.175mm). Only
one piece, two pole Neodymium sintered, or Ferrite (Ceramic) magnetic rotors are
permitted. The magnet length shall be 25.0 +/- 1.00mm not including any nonmagnetic
balancing material. The magnet outside diameter shall be a maximum of
12.51 mm, no tolerance, for the entire length of the magnet.
The shaft outside
diameter, where the magnet is mounted, shall be 7.25 +/- 0.150mm for the entire
length of the magnet. This dimension must be measurable without destroying the
rotor."
__________________
A mutually re-enforcing cascade of failure

"Failior [sic] crowns enterprise." Robert Goddard

I-Lap Scoring Systems http://www.rclapcounter.com/
robk is online now   Reply With Quote
Old 12-01-2011, 04:11 PM   #78
Tech Elite
 
DesertRat's Avatar
R/C Tech Elite Subscriber
 
Join Date: Mar 2011
Location: Sniffin the 'Sauce Fumes
Posts: 2,705
Trader Rating: 2 (100%+)
Default

Quote:
Originally Posted by robk View Post
120c batteries are useless if you draw 15A average. 120c on a 5000mAh pack is 600A, which you need about 500,000 MCM cable to handle. 10Ga AWG does not cut it. The stators are already handwound on Novaks...


Also....
"8.8.4.4.2 ROAR Spec Motors: External shaft diameter must be 0.125 inches (3.175mm). Only
one piece, two pole Neodymium sintered, or Ferrite (Ceramic) magnetic rotors are
permitted. The magnet length shall be 25.0 +/- 1.00mm not including any nonmagnetic
balancing material. The magnet outside diameter shall be a maximum of
12.51 mm, no tolerance, for the entire length of the magnet.
The shaft outside
diameter, where the magnet is mounted, shall be 7.25 +/- 0.150mm for the entire
length of the magnet. This dimension must be measurable without destroying the
rotor."
As we can only charge LiPo batteries to a certain voltage, the C-rating is roughly proportional to its voltage drop under load. Just hook up a voltmeter to your car in your hand and give the throttle a freewheel stab, the volts drop and not just a little. Power produced by an electric motor is proportional to the square of the voltage input, meaning a little extra can (in theory) go a long way. People are not going to stop trying, that's for sure. Rules will be bent, exploited, or otherwise fully explored.
__________________
I race toy cars for fun. If I need to explain, you'll never understand.
Current rides: Diggity DC4 Chassis #10. Losi JRX-S Type R. Losi 22 4.0, CRC Xi (retired), CRC Altered Ego Aluminum Chassis. Associated B4 based dirt oval late model.
WTB: Carpet racing in Arizona.
DesertRat is offline   Reply With Quote
Reply



Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are Off



All times are GMT -7. It is currently 05:34 PM.


Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net