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Old 05-09-2007, 02:25 AM   #31
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Please keep in mind that some feedback that is being posted here is very biased. I will admit that I am more biased towards the Mamba as I have switched over from my Novak SS5800+ & GTB 5.5. I also have a Mamba in my M18's & RC18B. I've had quite a bit of experience with all of these setups.

We have found that the GTB with a 4.5 or 3.5 as well as the Mamba Max 7700 have had issues with what appeared to have been cogging which was actually glitching when used in conjunction with the Spektrum receivers. The problems were resolved with both systems using a capacitor plugged into the aux slot on the receiver. The reason for this is that the ESC is drawing so much current from the batteries that the voltage drops below the minimum voltage the Spektrum receiver needs (I believe it was something like 5V).

One of my friends found out the hard way how gearing works. He had a Mamba Max which was overgeared in his truggy and what once again appeared to be cogging was actually a result of his overgearing. Basically, the ESC was drawing so much current that his batteries melted (literally). The solder desoldered itself and the batteries started cooking. This happened as he continued to drive his overgeared truggy. He did this to two battery packs thinking it was something wrong with the batteries or the Mamba Max itself. As it turned out, the problem didn't persist when he put it into a touring car with more reasonable gearing and no problems.

The first generation firmware on the Mamba (1/18th) did have cogging issues, but with the most current firmware update, this has been resolved which played a large role in my decision to actually consider switching from my Novaks to the Mamba Maxx.

I must say that I really didn't experience any cogging with my Novaks, but I really like the flexibility in gearing options and programming of the Mamba Maxx. However, the Mamba Maxx isn't ROAR legal and could pose some issues if you plan to race it.
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Old 05-09-2007, 05:33 AM   #32
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Meny guys from local track did have gliching problem with spectrum, and not driving electric car at all, on big gas cars, so i think that spectrum may be the problem. Try to contact Spectrum tech support, or try to swich back to old 27/40/72 Mhz.
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Old 05-09-2007, 06:22 AM   #33
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I know what you guys are talking about with the Spektrum radio glitch. I would lose steering or the steering would twitch, there would be throttle glitches which really scared me because the thing would speed up and wreck right into a wall. I actually first experienced this with the Novak GTB w/ 5.5r. This was quickly resolved by using a Spektrum receiver capacitor. Never happened since.

This isn't the same cogging or hesitation that I am talking about though. I have been using Spektrum receiver caps ever since, and now with a brand new radio with Spektrum Pro. The issue I am talking about is the hesitation and stuttering that will happen during acceleration, usually coming out of turns.

I think everyone will agree that the Mamba Max will cog if rolled backwards then given throttle, and it may cog starting from a dead stop. Even the Mamba Max fanboys will admit this. The problem is even this type of cogging is unacceptable for racing. If you have ever raced with the Mamba Max, you will know that this type of cogging is just as frustrating, if not more frustrating then the cogging that will happen upon acceleration.
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Old 05-09-2007, 06:36 AM   #34
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I will start use soon Mamaba Max with motors from Mamba,Orion, Speed Passion and LRP with 5 cell so i will report my results. I don't like LRP anymore(every year two new system with big coolers and fans;works but can't handle new hot motors so i decide to stop buying from LRP and save some money that way). Hope that Mamba Max can handle all hot motors but i will se how that works! Novak is still open option if Mamba fails.
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Old 05-09-2007, 09:46 AM   #35
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Quote:
Originally Posted by mattnin
I know what you guys are talking about with the Spektrum radio glitch. I would lose steering or the steering would twitch, there would be throttle glitches which really scared me because the thing would speed up and wreck right into a wall. I actually first experienced this with the Novak GTB w/ 5.5r. This was quickly resolved by using a Spektrum receiver capacitor. Never happened since.

This isn't the same cogging or hesitation that I am talking about though. I have been using Spektrum receiver caps ever since, and now with a brand new radio with Spektrum Pro. The issue I am talking about is the hesitation and stuttering that will happen during acceleration, usually coming out of turns.

I think everyone will agree that the Mamba Max will cog if rolled backwards then given throttle, and it may cog starting from a dead stop. Even the Mamba Max fanboys will admit this. The problem is even this type of cogging is unacceptable for racing. If you have ever raced with the Mamba Max, you will know that this type of cogging is just as frustrating, if not more frustrating then the cogging that will happen upon acceleration.
Had that same problem man, tc4 comming out of a sweaper, on the throttle it would just die for a second and then pick up. spectrum with a novak glitch buster. 4800 lipo and a co27 stocker. i have a dx3.0 so it came with another RX so i swaped it out and same thing. I just went out a got a gtx because i was only running stock. But i feel your pain. Tried damn near everything. Only thing i can sugest is go with fm rx.
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Old 05-09-2007, 11:09 AM   #36
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I still think your issues may be with gearing or something to do with your batteries not being able to supply enough current that the ESC and Mamba wants. I only had cogging issues with my 1/18th Mamba when it was first released which was eventually narrowed down to the firmware, so I do know how frustrating it is when it cogs while you are racing. However, once I had updated the firmware, I've never had any cogging and my Mamba Max has never cogged either ever since I bought it. As mentioned, earlier, my friend experienced cogging or stuttering with his truggy, but he later realized that he had overgeared (gear ratio too high as I think he was running something like 5.3 with larger diameter wheels & tires, so probably more like in the 4's or 3's). As he kept running his truggy during his two test runs, he literally melted down both battery packs. If you draw too much current from a battery it will overheat and if you do it too long, it will melt down. I really think this may be what is wrong. If you haven't contacted Castle Creations, yet, I highly suggest doing so before you get rid of your Mamba Max. Castle has great customer service and they really know what they are talking about, so it is definitely worth a try. If they can't help you solve the problem, then go buy a Novak or LRP or even a Tekin.
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Old 05-09-2007, 12:07 PM   #37
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Well here's what I learned about sensorless brushless motors years ago, Sensorless suffers from cogging at normal and low volts, sensorless cogging goes away at higher voltage. I learned that with my hacker brushless set up in 2003 when I ran the set up in my TC3. I ran it at 7 cells and I had alot of cogging once I jumped up to 12 cells the cogging stopped. I was able to do 3 speed runs at half track at 71mph with no cogging. I think for 7.2v-8.4v go sensored. My 3.5 novak never cogged on me and ran great in my TC4 with no problems. So if you own a sensorless brushless set up and it has high voltage output don't run the normal voltage run the max volts. Just gear the car properly. If you plan on running a track it's best to go sensored. My opinion is go sensored novak brushless. But at the end of the day everyone has there own personal preference. Take Care Guy's...
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Old 05-09-2007, 01:07 PM   #38
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Just give CC a call, they can even give you gearing suggestions. I've never had any cogging, interference issues with my Mamba Max. This using the original spektrum too. If you have a lap-top you can also take it to the track to try different adjustments to eliminate any cogging issues. This is actually the first I've read of anyone having problems with a Mamba.
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Old 05-09-2007, 06:31 PM   #39
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i too think that coging is a lack of volts in the battery
sooooooooooooooooooo lipos should work great.


i think.
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Old 05-10-2007, 06:44 AM   #40
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I had cogging with LIPOs, matched IB3800 batteries. These batteries are not good enough? I have been told, run a 3S lipo and you won't cog any more.
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Old 05-10-2007, 07:00 AM   #41
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Quote:
Originally Posted by mattnin
I had cogging with LIPOs, matched IB3800 batteries. These batteries are not good enough? I have been told, run a 3S lipo and you won't cog any more.
I had similar problems when I first used it. I turned the timing down to low and start power to low. The problem went away and it still had more torque than I knew what to do with. And that's in a 4wd tourer. What settings are you running?
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Old 05-10-2007, 07:40 AM   #42
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could it be due to your batteries?....
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Old 05-10-2007, 08:47 AM   #43
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Quote:
Originally Posted by mattnin
I had cogging with LIPOs, matched IB3800 batteries. These batteries are not good enough? I have been told, run a 3S lipo and you won't cog any more.
Running 3S will give you plenty of juice. But, is this for bashing or racing? What Li-Po have you run b4? I still suggest you adjust your starting curve on your P.C. and move your receiver away from the motor (if you havent done so already). If one of the buddies in your crew has the same motor, ask him to borrow his. Try his motor in your set-up. Problem persists, then it may be the ESC.
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