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View Full Version : New Owner - Miss Geico 24



Hunts99
05-19-2014, 07:52 PM
As a new member to the forums (and to RC boating) I was given the MG24 as a present over the holidays. Being in MN, I had to wait until April-ish to take her out. As others have said, the flex shaft is a pain to get out and no real help from Horizon Hobby. However I am still running into a few issues/questions that I was wondering if anyone could help me out with. The boat is completely stock with no modifications (including battery):

1) When we took it out the first time (and subsequent times until recently) the boat would jump off the line like it was going to go only to die/shut off for a few seconds then go the obligatory 2mph. Last night took it out and feathered the throttle very slowly and got it going the correct speed (or what I would assume would be the speed), but then when the throttle trigger hit the max point, it would shut off for 3 seconds and then go 2mph the rest of the way in. I was able to reset this by turning the boat off and unplugging and plugging in the battery. What would cause this? Is the stock ESC unable to handle the max load? Is the motor cutting out due to the same thing? I have tried to adjust the max throttle on the controller, but it is not resolving the issue.

2) When it was up to speed, it was 'porpoise-ing' a lot. Is this due to the majority of weight in the back end of the boat (e.g. COG is closer to the back)?

3) HH is selling a stainless prop, is it worth is to get the stainless over the factory plastic? I know rigidity would be a big feature, but could I squeeze a little more out of it in that case? http://www.proboatmodels.com/Products/Default.aspx?ProdID=PRB0154

4) If I were to want to upgrade to a brushless motor, where would be a good start? I do not need a 40mph boat, just something a little better than the stock. Would a new ESC needed as well (would think that Lipo's may be the best option as well)? I am completely new to RC boating, and there are so many options out there...how to sort through them. I would be looking for a swap (no interest in offset rudder and/or changing flex shaft diameter at this time). I have a connection through HH so I can get a discount through there.

Thank you in advance for all your help! I have family that are big into the RC car scene, but I am learning as I go on the boat

tlandauer
05-24-2014, 04:23 AM
Hi,
Welcome!
Let me be up front about my ignorance about this particular boat---I don't own it and usually I don't answer specific questions on a product which I don't have, so please bear with me.
Here is my opinion only:
1. What type of battery were you running? I ask this because if you are using a not -so-good Ni-MH battery, it could give bad running characteristics. According to the manual, if the voltage is not maintained after proper charge and before meaningful depletion, it will go to default soft running mode. a.k.a. LVC (low voltage cutoff) threshod. ( this is particularly true with Brushless ESC designed to run on Lipo batteries--- not really sure if your ESC has this feature but I assume it does). Also have you followed the instruction and calibrated the ESC with the radio, ( I could be wrong on this, the ESC may have auto programing feature and not require user input)
2. It could be the position of your battery and the struder's ( steerable outdrive) position , you need to dial it in ( again, I am not sure if any adjustment is possible, the manual did not mention that) . With her big brother MG29, there is a lot of this wah-wah-wah, many of us had to "blue-print" the sponsons and meticulously adjust the strut position and that of the batteries, do a search on that boat and you will know what I mean.
3. At present time I will stick with the stock plastic prop, for the stainless steel prop to really shine its ability, you need to thin it, balance it. It is a heavy prop and any inbalance will quickly translate to unwanted vibration and thus give you new problems such as accelerated wear and tear and reduced efficiency .
4. That is your choice, but you need a brushless ESC, and the motor would probably be Dynamite's 1500kv motor, if you feel adventurous, may be a 1800kv, but you need to make sure that there is enough room in the boat for two 2s Lipo batteries. Your total voltage will be at 14.8v.
You can pick a higher kv motor and run 3s lipo, thus using the existing battery platform.
If I were you I would investigate why your boat would not have full speed, if the condition of your battery is good and everything else seems normal, contact HH.
just my $.02
Good luck!

Hunts99
05-26-2014, 12:08 PM
Thank you for your response!
I am running the stock NiMH battery (2400mAh - 6cell). I think part of my problem is the battery. I was able to try a few 2S Lipo's yesterday and had similar problesms with shutting down. It would seem that it is overloading the ESC resulting in the LVC to kick in. Thank you for pointing that out to me, as that would seem like that is where my problem starting. The motor was a brushed motor and the ESC has the option to run NiMH or Lipo (by use of a switch). I think my best guess is a combination of a not-so-good NiMH battery and a bad 50A ESC.

I am thinking that I will probably upgrade the ESC and buying some Lipo batteries/charger. I think that would be a great start to see if the problem is fixed. Thanks for the information and the ideas. There is just so much to wade through when wanting to upgrade (i.e. motor shaft dimension and if it is bigger...needing new flexshaft/prop/collet nut...etc...etc..)

tlandauer
05-26-2014, 02:44 PM
You are welcome!
There was one possible explaination : for your first encountered problem---assuming the ESC was set to accept lipo, it will false read the voltage because the 6 cell NiMH will have lower voltage than a Lipo ( 2s) especially under load, in the case the ESC will kick in to LVC mode (LVC is low voltage Cut Off, it is a feature to PROTECT the lipo batteries which have a very delicate threshold on being over discharged). Once the ESC is in LVC, it will cut the throttle down to "zero" or slow down to a "soft" mode which means it will move very slowly for you to bring the boat back.
Now for the conflicting issue: It should have been ok when you tried to run the lipo, unless now you have mistakenly switched to NiMH mode.
So to recap: it will prematurally slow down if the ESC is not set to run on NiMH ( when in fact you are using such battery).
Not-so-good NIMH will drop its voltage rather quickly thus triggering early LVC.
LVC would not kick in to protect "over loading", most ESC's when connected to Lipo, they will self count the cell number and if the count exceeds the limit, it will not arm, so the protection cycle begins there.

joucca
06-13-2014, 05:13 PM
Hello

I agree that problem is in battery. I have same boat MG 24. Now running brushless setup. When I first bought this boat it was running somewhere around 2-3 mph. Peak charger that came with the boat did not charge the battery. Now original setup of MG is installed to my sons Victory EP 700 and it runs perfectly with 8.4V 7 cell battery.