R/C Tech Forums

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

Reply
 
Thread Tools Search this Thread
Old 08-22-2007, 11:40 PM   #106
Tech Elite
 
Join Date: Feb 2002
Posts: 2,208
Trader Rating: 44 (100%+)
Default

Quote:
Originally Posted by Delyt View Post
I run a 13.5 novak with a 3200 Orion lipo in the Kyosho RB5 and I get 20-25 minutes and the pack only get down to between 7.0-7.25v not even close to the ESC lipo cutoff range of 6.5v.
We have a guy who is running the 7.5 novak with the orion 3200 in a B4. After 12-15 minutes his pack was only down to 7.6v.

With the runtimes we are seeing there is no need to even use the 4800 packs. 3200 is more then enough.

Wow.
I tried my friendís fully charged Orion Lipo in my Rb5 a couple of weeks back.
Ran 1x 5 min heat with a Co27.
Then passed the car to another friend to have a go for 5 mins or less.
Towards the end, the car was visibily slow, almost as if the batt was dumping. So we stopped immediately.
I can only conclude the massive difference in runtime is due to the inefficient brushed motor?
__________________
YOKObori MOkei
wyl03 is offline   Reply With Quote
Old 08-23-2007, 04:26 AM   #107
Tech Regular
 
fhm555's Avatar
 
Join Date: Mar 2007
Posts: 457
Trader Rating: 2 (100%+)
Default

I watched a guy back in april run a novak BL and maxamps 6000 mah 7.4V equipped T4 with 9 gas trucks in a 30 minute main and he was just as fast down the front straight on the last lap as he was on the first. He finished 6th, proving that electric can run with gas and still be competative. That seems to be the trend around here among the hardcore electric guys, high capacity cells so they can run long mains. I had an MF I with a mamba maxx and 6000 mah maxamps lipo, but sold it after getting everything mounted up. The heavier motor and lighter battery shifted the COG way to the rear and I didn't feel like working out a new setup to compensate as I have so little time to devote to rc these days and my focus is currently on 8th nitro buggy. I'm hoping the XXXT CR with it's longer chassis will solve this problem.
fhm555 is offline   Reply With Quote
Old 08-23-2007, 08:08 AM   #108
Tech Adept
 
Join Date: Jul 2005
Location: Lillooet,BC
Posts: 127
Default

hey. So can you run 30 minutes straight and if yes does the club make you pit like the nitro's? Dan
danimal1965 is offline   Reply With Quote
Old 08-23-2007, 08:50 AM   #109
Tech Regular
 
fhm555's Avatar
 
Join Date: Mar 2007
Posts: 457
Trader Rating: 2 (100%+)
Default

In the 30 minute race he'd hit the pits for a stop and go every 5 to 7 minutes.

I wouldn't try a 30 minute race with a brushed motor, but so far the brushless rigs seem to be holding up just fine to extended mains.
fhm555 is offline   Reply With Quote
Old 08-23-2007, 09:52 AM   #110
Tech Elite
 
Turbo Joe's Avatar
 
Join Date: Nov 2003
Location: Corona, CA
Posts: 4,878
Trader Rating: 41 (100%+)
Default

Quote:
Originally Posted by wyl03 View Post
Wow.
I tried my friend’s fully charged Orion Lipo in my Rb5 a couple of weeks back.
Ran 1x 5 min heat with a Co27.
Then passed the car to another friend to have a go for 5 mins or less.
Towards the end, the car was visibily slow, almost as if the batt was dumping. So we stopped immediately.
I can only conclude the massive difference in runtime is due to the inefficient brushed motor?
Either it wasn't charged correctly (not full) or it's damaged. You should get 10-15 minutes easy. I do 10 minute mains all the time with geared-up 13.5 and 10.5 motors.
Turbo Joe is offline   Reply With Quote
Old 08-23-2007, 02:56 PM   #111
DN
Tech Apprentice
 
DN's Avatar
 
Join Date: Jun 2007
Posts: 76
Default

From what I have heard elsewhere and not in this forum is that the reason for reducing the voltage to five cell was that the manufacturers are having a difficult time keeping the speed controls from over heating with high draw mod motors. Many of the pros are finding issues with their speed controls overheating or even buring up. I think the manufacturers need to improve their products, despite how hard it may be. This sport after is more exciting when the speeds are increased.

As with the tire issue, maybe tire companies need to improve their products as well, so drivers are not burning them up so fast. It sound like much of the discussion is to keep the companies from having to improve.

I don't think people are driven away from rc because of the speeds. There are other classes to help build the skill to reach the higher mod ones. I think it is the cost however; but reducing one cell to save money or even save on the tires won't make a noticable difference.
DN is offline   Reply With Quote
Old 08-23-2007, 03:25 PM   #112
Tech Master
 
johnnyboy's Avatar
 
Join Date: Sep 2006
Location: Ontario, Canada
Posts: 1,634
Trader Rating: 28 (97%+)
Default

Quote:
Originally Posted by DN View Post
From what I have heard elsewhere and not in this forum is that the reason for reducing the voltage to five cell was that the manufacturers are having a difficult time keeping the speed controls from over heating with high draw mod motors. Many of the pros are finding issues with their speed controls overheating or even buring up. I think the manufacturers need to improve their products, despite how hard it may be. This sport after is more exciting when the speeds are increased.

As with the tire issue, maybe tire companies need to improve their products as well, so drivers are not burning them up so fast. It sound like much of the discussion is to keep the companies from having to improve.

I don't think people are driven away from rc because of the speeds. There are other classes to help build the skill to reach the higher mod ones. I think it is the cost however; but reducing one cell to save money or even save on the tires won't make a noticable difference.
All that stuff is from the on road end of thing and don't really apply to off road.
__________________
"Almost Live Race Coverage": www.johnnyboy.ca

.:Team Orion : JConcepts : B-Fast RC:.
johnnyboy is offline   Reply With Quote
Old 08-23-2007, 03:35 PM   #113
Tech Fanatic
 
Join Date: Apr 2007
Location: Socal
Posts: 887
Trader Rating: 42 (100%+)
Default

Lipos are still expensive since they are only allowed at club races. My son beats them with our 4200s. Going slower is faster since wheel spin will cause lost of traction. Just go easy on the finger and let them crash and we win every time. Gets boring when there is nobody that can drive clean, but they are fast but crash alot. I check the ad on the top of this forum and "wow" they are pricey. We have 6 to 8 min heats and mains, our batteries run fast the whole time. Small compamies that match cells are hurting like brushed motor guys.
desertraton is offline   Reply With Quote
Old 08-23-2007, 05:42 PM   #114
Tech Elite
 
Turbo Joe's Avatar
 
Join Date: Nov 2003
Location: Corona, CA
Posts: 4,878
Trader Rating: 41 (100%+)
Default

They're only "expensive" if you were going to replace them as often as your 4200's.

Since they last for 500-1000 cycles and a 4200 is good for a couple dozen, I would say they're far cheaper...not to mention the fact that you can sell off all your old NiMh stuff and charge a LiPo perfectly well with a $50-60 charger.



Quote:
Originally Posted by desertraton View Post
Lipos are still expensive since they are only allowed at club races. My son beats them with our 4200s. Going slower is faster since wheel spin will cause lost of traction. Just go easy on the finger and let them crash and we win every time. Gets boring when there is nobody that can drive clean, but they are fast but crash alot. I check the ad on the top of this forum and "wow" they are pricey. We have 6 to 8 min heats and mains, our batteries run fast the whole time. Small compamies that match cells are hurting like brushed motor guys.
Turbo Joe is offline   Reply With Quote
Old 08-23-2007, 08:19 PM   #115
DN
Tech Apprentice
 
DN's Avatar
 
Join Date: Jun 2007
Posts: 76
Default All that stuff is from the on road end of thing and don't really apply to off road.

Johnny Boy
Your right, but I was trying to reply to the discussion on the first page. I wasn't paying attention to the three others that followed, so my responce was late.
DN is offline   Reply With Quote
Old 08-24-2007, 12:24 PM   #116
Tech Addict
 
Join Date: Jul 2006
Location: Iowa
Posts: 637
Trader Rating: 9 (100%+)
Default

Comparing voltages at peak isn't necessarily an accurate indication of how it relates to the performance of the battery. What is important is the voltage that the battery sustains under load and over the span of the entire run. After the NiMH is run for seconds, the Li-Po is going to be pushing a higher voltage under heavy load with less resistance.

I personally think that voltage regulators would be awesome and create one of the most level playing fields imaginable at all levels of RC. The problem with voltage regulators is heat. Regulating a receiver pack that has a 3-5 amp draw on it is one thing, but regulating the power to an electric vehicle with much higher current draws creates a ton of heat...and heat is already an issue with todays high power, high current draw motors. What does a 6.5 BL setup draw 15-20 amp continuous and 60+ amp bursts?

Now, if all that sounds anti-LiPo...I actually think quite the opposite. I think LiPo are absolutely awesome and have both 3200 and 4800 Orion/Peak packs. The extra punch can be an advantage at times, but if everyone had them it would no longer be an advantage. C'mon ROAR get with the times! Running two classes with only two packs is one of the best things for the hobby.
glitchy is offline   Reply With Quote
Old 08-24-2007, 12:34 PM   #117
Tech Elite
 
POUNDITRACING's Avatar
 
Join Date: Dec 2005
Location: Newport, RI
Posts: 3,063
Trader Rating: 10 (100%+)
Default

ithe advantage to a Lipois that the power flows better. the .2v is nothing. The runtime dosen't make it better. I've seen many motore blow up in practice because we are in the habbit of running until the battery dies. If you look at all the Factory drivers in practice, they onle run about 2 min. It's all they need to see if they need to make changes. I've see RC go to a new track and only use 1pack for 3 hrs of practice. Put down a couple of laps and make a change.
__________________
Pound It Paints - http://www.rctech.net/forum/painting-designs-graphics-photography/270707-pound-paints-raymond-ramirez.html
RC Reveled - http://www.teamrcr.net
POUNDITRACING is offline   Reply With Quote
Old 09-10-2007, 08:37 PM   #118
Tech Elite
 
Mason's Avatar
 
Join Date: Oct 2004
Location: Ocala, Florida
Posts: 4,912
Default

is it possible to find out the contents of the proposed lipo and/or brushless package that has rumoured to be presented to ROAR? Dawn? Bob?
__________________
Mason McCombs
NewRed Hobbies & Indoor Facility
Off-Road, Dirt Oval, Crawlers & Pullers
Mason is offline   Reply With Quote
Old 09-11-2007, 07:31 AM   #119
Tech Rookie
 
Join Date: Sep 2007
Posts: 10
Default

Add me to the list of people back into electric R/C because of BL/Li-Po. In a nutshell, it's easy.
I like to race for fun but don't really have the time to jack with all of the black magic of turning comms and matching cells. When I get home from a day of racing I can clean up my car, look for anything that needs fixed and then toss it in the corner till the next weekend. I can get on with the rest of my life and not worry about what my batteries are doing. Then, come Friday I grab my track kit and within 5 minutes of walking in the door, I'm on the track.
Forget about voltage, forget about cell #'s, we are a generation of instant gratification and like it or not, the easier we make it to race, the more people we will have racing.
Scrogg is offline   Reply With Quote
Old 09-12-2007, 07:59 AM   #120
Tech Initiate
 
Join Date: Sep 2007
Posts: 38
Post

I'm running electric for 4 reasons: LiPo, Brushless motors, fewer parts (less maintenance), $$$.

I was only running nitro for the past 5 years because of the speed and long run times. Now my LiPo powered Rustler (on a 3s 5amp pack from maxamps) is faster than my nitro vehicles, and it runs for over 20 minutes. Although I'm trying to take care of some heat problems with the ESC.

I plan on racing it at my local track, if they have races that allow electrics - most people there have nitro truggies. If I get into racing (I use to play video games prfessionally CGI - PGR3) and the races don't allow lipo and brushless I wouldn't be interested because I want somethign that's comparable to nitro. Although I wouldn't be against a 7.4v limit because 11.1v is overkill in my rusty. I also think that electric trucks / cars shouldn't be forced to drive through the pits to mimik refueling, if they're limited to 7.4v. Then again, electircs probably shouldn't race nitro's....

I'm a noob with this stuff but wanted to offer my .02
R1R 7humbs is offline   Reply With Quote
Reply

Similar Threads
Thread Thread Starter Forum Replies Last Post
Is this roar legal? party_wagon Electric On-Road 0 01-30-2008 10:44 AM
Good non-Roar legal bodies and non legal wings imjonah Painting, Designs, Graphics and Photography 4 10-30-2004 09:42 PM
ROAR Legal 19T's? Griffin Electric On-Road 13 08-06-2004 02:46 AM
Roar Legal? nitromike Onroad Nitro Engine Zone 6 05-09-2004 10:40 PM
STS RS3 ROAR Legal AtomiK Other Items: For Sale/Trade or Wanted to Buy 0 01-22-2004 10:19 PM



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 11:57 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