Cold weather affecting speed?

[wakesurfer8]

I have a motley crew with stock electronics and upgraded ose flexshaft. I am running an m445 prop that is s/b. The lipos are 7.4v 100c 6000mah maxamps(they came with the boat when i bought it and i know they are very overpriced). I live in michigan and i ran my boat last about 2&1/2 weeks ago. The temp outside was probly about 40 degrees but no snow. With this setup, i only got 38 mph an i hear of people getting mid to upper 40's. I know that the cold weather affects the power of the lipos, but it still seems a little sluggish for this setup. I adjusted the strut more positive because it was running pretty tight. Would the cold weather and too negative on the strut slow the boat down that much? Also, i have read that the water is thicker when cold due to the molecules lumping together. I am fairly new to rc boating, but want more speed..... can someone help me out?

[Fluid]

It used to be that LiPos had higher resistance at temperatures under 100*F and thus put out less power. With curent tech LiPos this is much less pronounced. I was reminded of this yesterday when an older set of packs (~4 years old, 25C) was run in 75* weather. The first couple of laps looked pretty pathetic, but then as the packs warmed up the boat picked up quite a bit of speed. The effect is much less with current packs, but then I haven't run at 40*F for many years. I strongly suspect that the low temperatures are robbing you of power, not the minor changes in water density.


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[wakesurfer8]

alright thats what i thought, thanks

[wakesurfer8]

I raised the strut about 1/6 inch and it went 43.2 mph....that was probly the main problem. The deans connectors were so hot....170 degrees! Is this setup just drawing too much amps or what...esc and motor were in the 70's (water was in the 30's) and the lipos were 135 degrees. I ordered some 5.5mm bullet connectors....but the guy at the hobby shop told me that it wouldn't do anything. Is it true?....the esc has 14ga and lipos have 12ga wire. I am pretty worried about the deans getting so hot...what should i do?

[Doby]

What you should do is stop listening to the guy at the hobby shop. 5.5 mm connectors will substantially decrease the connector temps. Make sure you have a decent soldering iron to create a proper joint.

[Diesel6401]

I raised the strut about 1/6 inch and it went 43.2 mph....that was probly the main problem. The deans connectors were so hot....170 degrees! Is this setup just drawing too much amps or what...esc and motor were in the 70's (water was in the 30's) and the lipos were 135 degrees. I ordered some 5.5mm bullet connectors....but the guy at the hobby shop told me that it wouldn't do anything. Is it true?....the esc has 14ga and lipos have 12ga wire. I am pretty worried about the deans getting so hot...what should i do?

That is TERRIBLE advise. Most LHS guys don't know a whole lot about boats in general, mostly planes and cars where deans work. They also arent use to seeing the amp loads boats pull. You made the right choice, the 5.5mm bullets will be a HUGE help to you. Deans are the 1st thing that us boaters typically change out. My rtr's it is the first thing gone and the motor/esc connections are also changed out as well before the boat ever hits the water. Like doby mentioned it is advised to no longer take in information for that individual.

I realized the people at my LHS didn't know much about boating when the guy at mine tried to convince me the PB Widowmaker (which was a turd), was faster and a much better boat then the UL1 because it at a higher kv motor and that made all the difference. As I gave him the (your an idiot look) he let me be as I continued to browse.

[wakesurfer8]

he told me that deans have the lowest resistence on the market and the bullets would just melt together and create a bomb. Its only a 60 amp esc and i am running 100c maxamps and an m445 is this just too many amps for the esc to handle? Are the batteries too powerful? Prop too big? It seems to me that based on what he said that i would either need batteries with a lower c rating or bigger esc...i am scared because i dont want to have the batteries explode from the connectors melting..... He told me that the people on the forums dont know what they are talking about. he also said that no one has problems with the spartan with the traxxas plugs..... could this because it has a bigger esc?

[LarrysDrifter]

Its because the plugs arent the Spartans problems. They guy is a moron. He needs a job where he has zero interaction with the general public. You will find some good info here. Yes, there are morons here too that will give false information, but the 3 guys that posted in this thread already are good guys. There are many more, these are just examples.

[Diesel6401]

he told me that deans have the lowest resistence on the market and the bullets would just melt together and create a bomb. Its only a 60 amp esc and i am running 100c maxamps and an m445 is this just too many amps for the esc to handle? Are the batteries too powerful? Prop too big? It seems to me that based on what he said that i would either need batteries with a lower c rating or bigger esc...i am scared because i dont want to have the batteries explode from the connectors melting..... He told me that the people on the forums dont know what they are talking about. he also said that no one has problems with the spartan with the traxxas plugs..... could this because it has a bigger esc?

100c doesn't matter the esc only uses what it needs. If the esc senses the motor is pulling 60amps then it will ask for 60amps from the batteries. Just because your lipos can deliver a crap load of amps, doesn't mean the system is actually using them. You setup is fine, many are running that setup with no issues. The deans plugs are only rated at 70 amps or so, which means they are being pushed to there limits, and amp spikes from getting on plane are surely making the deans reach there limit. The reason the traxxas plugs aren't having problems is because they are rated higher then deans, or the boat explodes before the plugs can get hot :laugh:. The guy seems like a real joke IMHO. As soon as you change your plugs to 5.5mm bullets and get rid of the deans your issue will disappear. Theres are reason why no one here uses those connectors and your seeing the reason first hand. You don't need a bigger esc nothing is wrong with your setup, the deans are the issue. Don't let that moron talk you into anything, its obvious hes not boat savvy. The truth of the matter is this, I do boating, fly and have land vehicles. Boating is by far in a league of it's own, everything that works in the other 2 will surely fail in a boat! The amp draw is simply unmatched by the other 2.

*Make sure you run your boat with wide open throttle as much as possible, don't cruise around at 1/2 or 3/4 throttle. In a plane and car thats fine, do that in boat and get the marshmallows out cause your esc is gonna :flashfire:

[wakesurfer8]

alright i ran it again today and the deans were at 145 degrees... i think my temperature gauge misread it when it said 170.....is that too hot, should i still upgrade to 5.5mm bullets? thanks for all the answers and quick replies

[Diesel6401]

alright i ran it again today and the deans were at 145 degrees... i think my temperature gauge misread it when it said 170.....is that too hot, should i still upgrade to 5.5mm bullets? thanks for all the answers and quick replies

Change them out also! They are the weakest part of your setup! Only good can come from changing them out. If your not comfy with reg 5.5mm bullets use ec5 connections.

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[wakesurfer8]

alright... thanks again

[wakesurfer8]

i got the guy to do them today but he was still a little hesitant. He said it was because the esc wire is too small (14ga). Its the stock esc, and i am wondering if you guys did it on the stock esc as well. Just want to make sure that i didnt do something wrong....

[Diesel6401]

i got the guy to do them today but he was still a little hesitant. He said it was because the esc wire is too small (14ga). Its the stock esc, and i am wondering if you guys did it on the stock esc as well. Just want to make sure that i didnt do something wrong....

Yea we do it on the stock esc. Your right with what your doing, please cont. I can see why it says everyone on the forums are idiots, makes him realize how much he truely doesn't know. I take it since you went there to get them soldered that means you don't know how to is that correct? Gotta stop talking with that guy lol. He's out there. prob been rc'ing since the 40s and stuck in his ways, not in with the new so to speak. Our I could be 100% wrong.

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[desmobob]

I'll chime in and repeat what others have said... ditch the Dean's connectors AND the hobby shop guy's advice. You're in good hands here with advice from folks that have run boats for a long time. And if by chance some noob here gives you some bum advice, someone will jump in immediately to give you the straight scoop.

You'll soon find that the great folks on this forum will give you good advice and do anything they can to insure you'll enjoy the fast electric RC boating hobby!

Take it easy,
desmobob

[wakesurfer8]

alright i really appreciate the help guys

[Diesel6401]

Can you post of pic of the items you let the guy at the lhs solder? I don't trust the guy based on his advice. Just wanna make sure he did things correct.

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[wakesurfer8]

i took a picture but its not letting me upload it...he said that it was good(hold on now, i know what your thinking) and i looked it over carefully and i know that it is good. I know that i am still a pretty new to this but i know that the connections were good and it all works. I even tested it and it works like a charm...if it is necessary, i can tell you what connector is on each wire....

[Diesel6401]

i took a picture but its not letting me upload it...he said that it was good(hold on now, i know what your thinking) and i looked it over carefully and i know that it is good. I know that i am still a pretty new to this but i know that the connections were good and it all works. I even tested it and it works like a charm...if it is necessary, i can tell you what connector is on each wire....

Standard on batteries: Female on +, male on -
Standard on esc: Female on -, male on +
* Make sure the bullets are covered very well by heatshrink.

There also should not be any jumper between the esc. You should only have 2 power wires coming off the esc, using the bullets eliminates the need for the series jumper.

[wakesurfer8]

so i could just cover up the bullets that wouldnt need to be used.... it wouldnt hurt anything if i kept the jumper in...

[Diesel6401]

I had a feeling he was going to do that. The jumper adds unnecessary resistance!

To connect your batteries in the series circuit without the jumper take the + of one battery and connect it to the - of the other battery. The safest way to hook up your setup is to hook 1 battery negative to the esc negative, take the second battery + hook it to the esc + and last of all connect the 2 batteries. That will help reduce the chance of shorting out a battery to itself which is easy to do with bullets.

[wakesurfer8]

alright i see what you mean... i will try that out tomorrow

[wakesurfer8]

what are some good upgrades to make after 5.5mm bullets? ie.. power systems, scuffing, shapening rudder, rounding bottom of rudder, blueprinting the hull-how is this done and is it necessary?

[Diesel6401]

what are some good upgrades to make after 5.5mm bullets? ie.. power systems, scuffing, shapening rudder, rounding bottom of rudder, blueprinting the hull-how is this done and is it necessary?

The most beneficial and cost effictive options are to blueprint, scuff tune and adjust. Add a good prop like the m445 which I believe you are running and start tuning. That will yield the best results. Slapping new power or more voltage as must beginners do will typically yield poor results or failures. Take your time and do things correctly. Took me a long time and a lot of money to figure that out!

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[wakesurfer8]

is it necessary to blueprint the hull on the MC and how exactly would i blueprint it?

[Diesel6401]

is it necessary to blueprint the hull on the MC and how exactly would i blueprint it?

Anytime you have a mas produced rtr hull blueprinting is never a bad idea. Darin Jordan did a very nice blueprinting write-up in the PB section.

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[wakesurfer8]

i cant find it... could you send me a link?

[Diesel6401]

i cant find it... could you send me a link?

Sorry I can't search from the tapatalk app, its in the miss geico section. There maybe a tread called MG Race Prep or something like that.

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