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Old 01-09-2009, 05:22 PM   #31
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I heard setting the throttle end point back is a bad thing though. Does anyone know why that is? It's just simply giving the motor less throttle from the ESC so I don't see the problem. Does it have something to do with the lower efficiency from partial throttle compared to full throttle?
It's a myth, perpetuated by somebody that was "told" by "someone" that it would hurt the ESC. He then had problems, and incorrectly blamed his EPA setting. Just so you know, I have an identical setup to the guy that had problems. I used my EPA to set up the car, just like ANY OTHER CAR, and it works fine.
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Old 01-09-2009, 06:25 PM   #32
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when i run the 2000kv medusa on 6s i use 60% epa.

There is more noticable cogging with the reduced epa then at full allowed throttle. Probably just something with the esc. Theoretically there should be no problems encountered because the fets are just letting less current through.

Efficiency is dependent on the motor and the current being drawn. I would try and match your batts, motor and gearing to be able to use 100% epa. going to 60% like i had to do is not advised.
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Old 01-09-2009, 06:40 PM   #33
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Originally Posted by R40Victim View Post
It's a myth, perpetuated by somebody that was "told" by "someone" that it would hurt the ESC. He then had problems, and incorrectly blamed his EPA setting. Just so you know, I have an identical setup to the guy that had problems. I used my EPA to set up the car, just like ANY OTHER CAR, and it works fine.
this comes from brushed esc era. a brushed esc is at its most efficent at full throttle because it basicly turns into a solid connection.
a brushless esc is always switching from what i have been told by charlie at novak so it dosent matter.
as for your esc cogging more with the endpoint turned way down i can see that. it is basicly making your trigger to esc input more sensitive.
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Old 01-09-2009, 08:00 PM   #34
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I can't say one way or the other since I haven't even driven a brushless setup yet. I'm getting back into the hobby after a few year "absence". I've got a Tx/Rx and 8ight kit but that's it so far. Still doing homework on components. The CC website is where I heard about the throttle endpoint thing.

http://www.castlecreations.com/suppo....html#monster1

Regardless, I'll see where I stand once I get things built and setup. If running the endpoint short causes excessive heat then I'll go from there. But it sounds like a few haven't had any problem so I'm guessing I won't either.
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Old 01-09-2009, 08:22 PM   #35
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Interesting that Castle would say that - I mean they should know what they're talking about

In my way of thinking however it just doesn't make sense. Running at full trigger pull with the EPA set to 80% is the same as running at 80% trigger pull with the EPA set to 100% - as far as the ESC sees it. The transmitter is just sending an 80% signal to the receiver in both cases, and the receiver sends 80% signal to the ESC.

It's really not possible to get a setup where you are running 100% for more than a few seconds unless you're running oval or a very slow setup. Any off-road track is going to have a small percentage of overal length in high speed straights, everything between is throttle control. If you were setup to have 100% throttle from corner to corner you're going to be very slow compared to everyone else.
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Old 01-09-2009, 08:38 PM   #36
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^ Pretty much what I was thinking. Plus, later in the FAQ:

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Answer 3: If you owned a Ferrari, would you have to drive it full throttle through your neighborhood? The system is not uncontrollable; your finger just needs time to learn how to control the throttle trigger on a high power setup.
Isn't that the same thing as setting the endpoint? Just one is manual and the other is set.

edit: I apologize about the thread derailment.
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Old 01-09-2009, 10:21 PM   #37
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No, you're absolutely right. However, if it makes him more comfortable to limit his throttle, shouldn't he have the freedom to do so?

Back on topic!

EPA is simply a method to limit the signal input; it does NOT damage your brushless ESC to use it like simple tuning or a "comfort method".
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Old 01-10-2009, 05:57 AM   #38
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If I had a Ferrari I probably would drive it full speed through my neighborhood by the way.
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Old 01-10-2009, 08:29 AM   #39
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Anyway..... getting back to batteries and run time that this thread was started for. Yesterday I went out for a full practice day at FTR the link is in my sig. its an inddor track tight with a fast straight hard pack pink taper track.
8ight conversion 15/45 MMM/2200kv combo
using 2 zippy-h 20c 5000 4s packs and 1 losi hard case 5000 25c 4s pack
I was averaging 18-21 with all 3 packs. indoor temp was 45
motor 115
ESC 90
Batts 85 The hard case was a little less for obvious reasons(the hard case)
I think once I get a 13T or 14T pinnion the motor should have less current draw because I would be loading the motor less. this should work because I am way to fast for racing. I can easily pull for the nitros on the straight.
we will see next time.
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Old 01-10-2009, 01:25 PM   #40
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Thank you everybody for posting set-ups, track layout, and run times. Very helpfull.

1) Anybody die hard enough to know if the Enerland cells end up getting 2 to 4 times more cycles than the cheaper cells? That is about the only thing left that may justify the price.

2) Build quality & aluminim vs copper tabs is not as good. How difficult would it be to rebuild a brand new chinese pack?
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Old 01-10-2009, 02:49 PM   #41
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Originally Posted by WALZ View Post
Thank you everybody for posting set-ups, track layout, and run times. Very helpfull.

1) Anybody die hard enough to know if the Enerland cells end up getting 2 to 4 times more cycles than the cheaper cells? That is about the only thing left that may justify the price.

2) Build quality & aluminim vs copper tabs is not as good. How difficult would it be to rebuild a brand new chinese pack?
I have a hard time believing the enerland cells are going to last substantially longer than the Zippys. Even if they last longer, the you just replace a zippy at 1/3rd the cost of a typical enerland pack. The cost premium isn't worth the extra money for typical usage IMHO.

Just buy a bunch of Zippys. You will not be disappointed. I have a hard time justifying paying premium prices for lipos anymore.
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Old 01-10-2009, 06:35 PM   #42
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I spoke to Kendall at Amainhobbies last week about the ProTek R/C 4S packs. He is going to have a 4S 35C 4000mah pack and a 4S 35C 5200mah pack both in a hard case. They should be VERY atractively priced. The ProTek R/C 2S hard cased packs have done amazingly well. I have been running the 30C soft 2S 4000mah packs since the summer (two packs wired in series) and they have ran great! I can run them down to 95-96% capacity with a power hungry Neu 1512 1.5D (3200/kv) and they don't even get warm!
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Old 01-10-2009, 07:20 PM   #43
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I get conflicting info...should the mmmv3's fan come on upon intial power up? Mine does not but another racer todays does! Running a neu 1512 2,5d I had the hesitation blues all day. After a couple of minutes of running on a fully charged pack (5s, several different packs) my car would hesitate when pinned. At one point I had to sit on the track for about 1 minute then it ran again. The motor temp never went over 150-160. After running and nursing the MBX6 through about 10min of a 15 mnute main i stopped, the pack was hot and and I had no punch. The motor was was 160 the SC 's fan nver came on that I could tell.....whats going on?
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Old 01-10-2009, 07:38 PM   #44
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I actually run zippy 5s 5000's in my 8ight-t, and I do race and the weight is fine.. no issues at all. The packs are worth the cost but they are not as good as higher end packs, but again worth the money.

My 2c; I also have some Elite 35c 5000 4s packs and they are as fast out on the track as ALL my 5s packs (fp's, zippy's, Neu) The elite are that much better, they just hold voltage under load better. If you are doing speed runs the higher voltage in the zippy's obviosly will take the crown, but on a track with stop and go running the Elite 35c 5k's kick the zippy's all over the place. My FP's evo25's are nice, I have some poyquest 30c, some SMC 28c's, and some Neu 25c packs and all of them bow down for the elites.


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Old 01-11-2009, 06:34 AM   #45
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Quote:
Originally Posted by Thopper View Post
I get conflicting info...should the mmmv3's fan come on upon intial power up? Mine does not but another racer todays does! Running a neu 1512 2,5d I had the hesitation blues all day. After a couple of minutes of running on a fully charged pack (5s, several different packs) my car would hesitate when pinned. At one point I had to sit on the track for about 1 minute then it ran again. The motor temp never went over 150-160. After running and nursing the MBX6 through about 10min of a 15 mnute main i stopped, the pack was hot and and I had no punch. The motor was was 160 the SC 's fan nver came on that I could tell.....whats going on?
My esc fan never comes on. but I have never had the esc over 110. you are temping your motor. you also need to temp your packs and esc. If your pack and esc are warm to hot and your motor is warm. you could be just pulling to many amps for the lipo to handle. or you have a wiring problem some where.
you would be better of posing this in the Mamba Monster or 1/8 brushless thread. you might find some one their that has had similar issues.
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