R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 03-25-2011, 02:34 PM   #1216
Tech Master
 
Join Date: Jan 2009
Location: Powder Springs, GA
Posts: 1,859
Trader Rating: 2 (100%+)
Default

hooked up my 13.5 up, but not in car, turned my throttle travel from 150 to 50, turned it on, pulled trigger down for 45sec and I could not touch it anymore, super hot. I think its broke
__________________
!!!!!!!!!!!!!!!!!!!!!!!!!!!SHON HARDING!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!SWEEP TEAM DRIVER!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!VIPER R/C SOLUTIONS TEAM DRIVER!!!!!!!!!!!!
!!!!! OFFICIAL TEAM TURTLE TRAX TEAM DRIVER!!!!!!!
!!!!!!!!NEXT LEVEL ADDICTIONS CUSTOM PAINT!!!!!!!
synap2012 is offline   Reply With Quote
Old 03-25-2011, 02:46 PM   #1217
Tech Master
 
Join Date: Mar 2003
Posts: 1,464
Trader Rating: 2 (100%+)
Send a message via AIM to goop
Default

were you doing this with the tires off the ground, if so that is the worst thing you can do for the motor and speedo.
__________________
Hurricane Motorsports
Team Trinity

TOP Racing - Gravity Rc - Contact tires - KO Propo - Competition Electronics
goop is offline   Reply With Quote
Old 03-26-2011, 06:58 AM   #1218
Tech Master
 
Join Date: Jan 2009
Location: Powder Springs, GA
Posts: 1,859
Trader Rating: 2 (100%+)
Default

nope motor was just sitting on the table, but I am curious why would it harm the speedo/motor to gas the throttle while the tires off ground?
__________________
!!!!!!!!!!!!!!!!!!!!!!!!!!!SHON HARDING!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!SWEEP TEAM DRIVER!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!VIPER R/C SOLUTIONS TEAM DRIVER!!!!!!!!!!!!
!!!!! OFFICIAL TEAM TURTLE TRAX TEAM DRIVER!!!!!!!
!!!!!!!!NEXT LEVEL ADDICTIONS CUSTOM PAINT!!!!!!!
synap2012 is offline   Reply With Quote
Old 03-26-2011, 07:07 AM   #1219
Tech Master
 
Join Date: Mar 2003
Posts: 1,464
Trader Rating: 2 (100%+)
Send a message via AIM to goop
Default

i have personally seen someone do this and there rotor exploded and shorted out the motor and burned up the speedo. also free reving anything is bad.
__________________
Hurricane Motorsports
Team Trinity

TOP Racing - Gravity Rc - Contact tires - KO Propo - Competition Electronics
goop is offline   Reply With Quote
Old 03-26-2011, 03:22 PM   #1220
Tech Master
 
Join Date: Jan 2009
Location: Powder Springs, GA
Posts: 1,859
Trader Rating: 2 (100%+)
Default

hmmm.... there must have been something else wrong. Can you explain in detail why a motor would expload and speedo give out, just by testing it on the bench????
__________________
!!!!!!!!!!!!!!!!!!!!!!!!!!!SHON HARDING!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!SWEEP TEAM DRIVER!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!VIPER R/C SOLUTIONS TEAM DRIVER!!!!!!!!!!!!
!!!!! OFFICIAL TEAM TURTLE TRAX TEAM DRIVER!!!!!!!
!!!!!!!!NEXT LEVEL ADDICTIONS CUSTOM PAINT!!!!!!!
synap2012 is offline   Reply With Quote
Old 03-26-2011, 03:30 PM   #1221
Tech Fanatic
 
primusblowsgoat's Avatar
 
Join Date: Jul 2004
Location: Pingree Grove, IL
Posts: 987
Trader Rating: 14 (100%+)
Send a message via AIM to primusblowsgoat Send a message via Yahoo to primusblowsgoat
Default

Quote:
Originally Posted by synap2012 View Post
hmmm.... there must have been something else wrong. Can you explain in detail why a motor would expload and speedo give out, just by testing it on the bench????
The motors are not designed to go to full revs with zero load. I dont have specifics of the physics involved, but they are designed to have wheels on the ground. Even going to full revs with the motor in the car with the wheels in the air for prolonged periods is not a good thing.
__________________
Schumacher Racing
Schumacher Cat SX2
Schumacher Cougar SV
primusblowsgoat is offline   Reply With Quote
Old 03-26-2011, 03:58 PM   #1222
Tech Fanatic
 
macdude's Avatar
 
Join Date: Feb 2010
Posts: 925
Trader Rating: 3 (100%+)
Default

Quote:
Originally Posted by synap2012 View Post
hmmm.... there must have been something else wrong. Can you explain in detail why a motor would expload and speedo give out, just by testing it on the bench????
In a brushless rotor the magnets are glued to the shaft. Most have a failure point in the RPM range. You will most likely never achieve this range if the motor is under load. However on the bench there is nothing preventing it from spinning up past what it is designed to take. When you do you will have failure in rotor, which will most likely short out the stator windings and cause failure. It doesn't explode like in a hollywood movie. But the rotor does delaminate. I have had one rotor fail while running. It was not catastrophic as only a small portion of nickel plating came off. But is was enough to seize the front bearing and grind the whole thing to a halt.

Running the motor up and down for a couple of seconds though should not cause the ESC to get too hot to touch. I have been testing mine right now and it just gets a little warm. Unless I put the timing on 12 then it gets hot but I can still touch it.
__________________
---------------
KO Eurus / Orca / MMP / XB2 / 22-4 /
macdude is offline   Reply With Quote
Old 03-26-2011, 04:05 PM   #1223
Tech Elite
 
theisgroup's Avatar
 
Join Date: Apr 2002
Posts: 3,191
Trader Rating: 10 (100%+)
Default

Quote:
Originally Posted by synap2012 View Post
hmmm.... there must have been something else wrong. Can you explain in detail why a motor would expload and speedo give out, just by testing it on the bench????
It's just like reving a real car's engine to redline while in neutral. All the power that the motor produces has no where to go, so it is applied to internal components of the engine. So on a brushless motor that is rev'd to it limit, it applies all the power to the rotor.

When the rotor explodes, I am sure the sensors don't read correctly. So the Speedo may fire poles in the wrong order. When that happens you could fire a single pole in both directions meaning +/- and -/+. Or the back end generated from a frozen rotor could be enough feedback to really damage the Speedo.
__________________
yang lai

Team Tamale | Team Tekin | RCAmerica | Speedmerchant | Speedzone RC | EA Motorsports | Ko Propo USA | eXpress Motorsports | Parma/PSE

Last edited by theisgroup; 03-26-2011 at 04:51 PM.
theisgroup is offline   Reply With Quote
Old 03-26-2011, 04:12 PM   #1224
Tech Elite
 
Johnny Wishbone's Avatar
 
Join Date: Feb 2006
Posts: 3,419
Trader Rating: 6 (100%+)
Default

I actually saw a racer explode a rotor when his car barrel rolled at the end of a long straight, he didn't let of the throttle and when it unloaded it broke up. It was like a 2 cycle kart when the piston seizes at the end of the straight.
__________________
Gary Lanzer
Johnny Wishbone is offline   Reply With Quote
Old 03-27-2011, 09:51 AM   #1225
Tech Master
 
Join Date: Jan 2009
Location: Powder Springs, GA
Posts: 1,859
Trader Rating: 2 (100%+)
Default

Makes some sense but, every engine that comes from a factory has been on a dyno of some kind with no load! I check to see if a motor is balanced by setting it in my hand/table and giving a blip of power, the motor if its in good balance wont jump all over the place. Something I have done for years!

I mean yes, if you turn everything up and slam the throttle for obscene periods of time I can see things coming loose, but checking electronics out of the car has never givin me problems! been in the hobby 16+ years
__________________
!!!!!!!!!!!!!!!!!!!!!!!!!!!SHON HARDING!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!SWEEP TEAM DRIVER!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!VIPER R/C SOLUTIONS TEAM DRIVER!!!!!!!!!!!!
!!!!! OFFICIAL TEAM TURTLE TRAX TEAM DRIVER!!!!!!!
!!!!!!!!NEXT LEVEL ADDICTIONS CUSTOM PAINT!!!!!!!
synap2012 is offline   Reply With Quote
Old 03-27-2011, 10:13 AM   #1226
Tech Elite
 
theisgroup's Avatar
 
Join Date: Apr 2002
Posts: 3,191
Trader Rating: 10 (100%+)
Default

I just provide the info. I have never shattered a rotor or had a prob with any of my brushless speeds. Do with it what you will
__________________
yang lai

Team Tamale | Team Tekin | RCAmerica | Speedmerchant | Speedzone RC | EA Motorsports | Ko Propo USA | eXpress Motorsports | Parma/PSE
theisgroup is offline   Reply With Quote
Old 03-27-2011, 10:18 AM   #1227
Tech Master
 
Owen RaCing's Avatar
 
Join Date: Jan 2007
Location: Mountain Valley
Posts: 1,940
Trader Rating: 17 (100%+)
Default

Quote:
Originally Posted by synap2012 View Post
Makes some sense but, every engine that comes from a factory has been on a dyno of some kind with no load! I check to see if a motor is balanced by setting it in my hand/table and giving a blip of power, the motor if its in good balance wont jump all over the place. Something I have done for years!

I mean yes, if you turn everything up and slam the throttle for obscene periods of time I can see things coming loose, but checking electronics out of the car has never givin me problems! been in the hobby 16+ years
But you held the throttle for 45 seconds, not just a few blips!

People are giving you the answers, but your choosing not to take them. And good dyno's have a load of some sort.
__________________
powered by anti-anxieties, sarcasm and chipotle
Owen RaCing is offline   Reply With Quote
Old 03-27-2011, 10:19 AM   #1228
Tech Elite
 
Johnny Wishbone's Avatar
 
Join Date: Feb 2006
Posts: 3,419
Trader Rating: 6 (100%+)
Default

Quote:
Originally Posted by synap2012 View Post
Makes some sense but, every engine that comes from a factory has been on a dyno of some kind with no load! I check to see if a motor is balanced by setting it in my hand/table and giving a blip of power, the motor if its in good balance wont jump all over the place. Something I have done for years!

I mean yes, if you turn everything up and slam the throttle for obscene periods of time I can see things coming loose, but checking electronics out of the car has never givin me problems! been in the hobby 16+ years
Actually good dynos use some kind of load.
__________________
Gary Lanzer
Johnny Wishbone is offline   Reply With Quote
Old 03-27-2011, 10:42 AM   #1229
Tech Champion
 
Scottrik's Avatar
 
Join Date: Sep 2004
Location: Billings, MT
Posts: 6,212
Trader Rating: 245 (100%+)
Default

Quote:
Originally Posted by synap2012 View Post
every engine that comes from a factory has been on a dyno of some kind with no load!
Uh...by it's nature, if it's a dyno, it applies a load. A "dyno" with no load is a test stand.

As far as free-revving, a short blip probably never hurt anything (unless dealing with a low wind mod motor), but you describe a 45 second torture test.

If you have doubts about the veracity of the information you are receiving, have a look at

http://www.teamnovak.com/tech_info/f...g_warning.html

From Novak's own site. I'm figuring they know more than you, I (25 years in the hobby now) and anyone else who has posted in this thread combined about brushless motors and failure modes therein. There probably isn't much they haven't seen.
__________________
Congressmen should wear uniforms like NASCAR drivers so we can identify their corporate sponsors.

THE REVOLUTION WILL NOT BE TELEVISED -Gil Scott-Heron (1949-2011)
Scottrik is offline   Reply With Quote
Old 03-27-2011, 12:40 PM   #1230
Tech Master
 
Join Date: Jan 2009
Location: Powder Springs, GA
Posts: 1,859
Trader Rating: 2 (100%+)
Default

you guys are right, I mis-lead, my 45 sec test was just blipping the throttle while having my end trim points down from 150 to 50. It took the ESC about 45 sec to become to a point that I could not touch it.

While the speedo was in the car it only lasted about 10sec before it was to hot.

I am sorry for not being more precise about my post.

O-by the way who said I was not listening to their answers??!??

I am completely aware of what they said

Thanks everybody!

p.s. sent esc to KO I will here about what was wrong in a few weeks
__________________
!!!!!!!!!!!!!!!!!!!!!!!!!!!SHON HARDING!!!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!!!!!!!!!!!!SWEEP TEAM DRIVER!!!!!!!!!!!!!!!!!!!!!!!!
!!!!!!!!!!!VIPER R/C SOLUTIONS TEAM DRIVER!!!!!!!!!!!!
!!!!! OFFICIAL TEAM TURTLE TRAX TEAM DRIVER!!!!!!!
!!!!!!!!NEXT LEVEL ADDICTIONS CUSTOM PAINT!!!!!!!
synap2012 is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Tekin RS ESC sensored Jeff Cuffs Electric On-Road 23359 10-02-2016 06:57 AM
best esc for touring car devin4444 Electric On-Road 48 05-02-2016 10:01 AM
Foam tire spec chassi!! Team_Elli Electric On-Road 15 07-28-2009 07:26 AM
KO BMC vs SP GT2.0 vs LRP SXX krat Electric On-Road 36 07-11-2009 07:18 PM
Orion Vortex BL Race ESC dr_hfuhuhurr Radio and Electronics 29 03-02-2009 07:46 AM



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 12:33 AM.


We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
Powered By: vBulletin v3.9.2.1
Privacy Policy | Terms of Use | Advertise Content © 2001-2011 RCTech.net