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Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 11:45 am
by JosephS
Re: Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 1:41 pm
by XLR8
hahaha... Yeah perhaps but when that happens to my cars, I just attribute it to my terrible soldering skills.

Re: Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 1:58 pm
by juicedcoupe
XLR8 wrote: ↑Sat Nov 13, 2021 1:41 pm
hahaha... Yeah perhaps but when that happens to my cars, I just attribute it to my terrible soldering skills.
This.
A lot of other things would have melted before the solder.
It doesn't look like the tabs on the motor were properly tinned. The solder joints also look a little cold. If you don't already use one, maybe try a chisel tip.
Re: Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 4:32 pm
by XLR8
Or if you're like me, look for a soldering iron that gets hotter than a cup of coffee.
I'm looking for a brand that expresses the iron's max. temperature relative to the heat from the sun. I want something that glows and melts rocks.

Re: Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 4:46 pm
by JosephS
juicedcoupe wrote: ↑Sat Nov 13, 2021 1:58 pm
XLR8 wrote: ↑Sat Nov 13, 2021 1:41 pm
hahaha... Yeah perhaps but when that happens to my cars, I just attribute it to my terrible soldering skills.
This.
A lot of other things would have melted before the solder.
It doesn't look like the tabs on the motor were properly tinned. The solder joints also look a little cold. If you don't already use one, maybe try a chisel tip.
There was a fair bit of smoke. The ESC was hitting thermal shut down and the motor and battery wires were hot. The tab was hot enough that even after the walk to see what was going on the solder was still liquid. That poor solder joint likely saved the car.
Though I will try those soldering tips.
Re: Ok maybe it is just a tad bit over geared
Posted: Sat Nov 13, 2021 5:15 pm
by juicedcoupe
A poor solder joint will have higher resistance, which will create more heat at an already unstable joint.
That higher resistance will also put more load on the esc, battery, and wiring.
And as I said before, a 13T probably isn't ideal for bashing in a truck. Throw in high capacity lipo batteries and it becomes even less ideal.
Re: Ok maybe it is just a tad bit over geared
Posted: Sun Nov 14, 2021 12:45 pm
by JosephS
juicedcoupe wrote: ↑Sat Nov 13, 2021 5:15 pm
A poor solder joint will have higher resistance, which will create more heat at an already unstable joint.
That higher resistance will also put more load on the esc, battery, and wiring.
And as I said before, a 13T probably isn't ideal for bashing in a truck. Throw in high capacity lipo batteries and it becomes even less ideal.
Somehow I missed the note on the 13T motor.
So this is my first bashed truck build. Would I just be able to drop gearing and put things back about right, or do I need a motor change?
Would a brushless handle this better? Would the 550 brushed motors from a traxxas truck right to drop in?
Without doubt I need to drop the gearing. I will also pull the drive train apart to make sure there isn't binding or something else causing an issue.
I have an 550 4 pole 5.5 turn Novak brushless motor that used to be in a 4x4 SCT. I thought that may be a bit to much for a vintage rc10t, would the t2 handle that?
Would running a 3s to increase voltage, but dropping the gearing, reduce the heat generated since less amperage would be pulled for the same rpm at the wheel?
Re: Ok maybe it is just a tad bit over geared
Posted: Sun Nov 14, 2021 2:33 pm
by jwscab
Honestly, stick with 2 cells, and if you go with brushless, stick with something above 10.5 turn or 15 turn brushed. They will be plenty fast enough to destroy things.
A brushed motor is really going to only run for 6 minutes or so before you cook it's guts out, even with sane gearing. Modified motors really just don't last a long time. Really, the nicad capacity kept the motors alive because they would dump by the time the motors got that hot. Lipos have such higher capacity and hold at the voltage of a 7 cell nicad that things get out of control in a hurry
Re: Ok maybe it is just a tad bit over geared
Posted: Sun Nov 14, 2021 3:56 pm
by juicedcoupe
Also, keep the timing conservative. I usually keep trucks around 5°, if any.
If given the choice between gearing down a low turn motor or using a milder motor, I will go with the milder one every time. Even when geared down, hotter motors are still harder on parts.
I used to have a 23T Orion in one of my trucks, and actually had it geared up a little. It was still fast enough to get you in trouble but could run several packs (nimh) in a row without overheating.
Most of my trucks have 17T or higher motors in them. I think one has a 15T but it isn't likely to see much run time (white arm truck).
Re: Ok maybe it is just a tad bit over geared
Posted: Sun Nov 14, 2021 7:20 pm
by RC10th
Agreed the brushed motor route isn't a good one to take, mod motors only used to run 5 - 6 minutes back in the day before dumping, lipos run forever, lol.
Go brushless if you can but keep it sane, say 7.5T - 10.5T, and stick to 2 cell lipo.
The gearbox is pretty robust and can handle just about anything you can throw at it provided it's adjusted properly. I personally run a Reedy Sonic 8.0T in my "basher" T2 and it's great, it would run all day without getting hot.
Re: Ok maybe it is just a tad bit over geared
Posted: Mon Nov 15, 2021 12:08 am
by XLR8
RC10th wrote: ↑Sun Nov 14, 2021 7:20 pm
Agreed the brushed motor route isn't a good one to take, mod motors only used to run 5 - 6 minutes back in the day before dumping, lipos run forever, lol.
Go brushless if you can but keep it sane, say 7.5T - 10.5T, and stick to 2 cell lipo.
The gearbox is pretty robust and can handle just about anything you can throw at it provided it's adjusted properly. I personally run a Reedy Sonic 8.0T in my "basher" T2 and it's great, it would run all day without getting hot.
I've never ran anything lower that 10.5t but I have this Castle ? motor that's a 4600kV (or maybe it's 5600kV

) that came in some car I got from ebay a while back that I might try in this monster truck I'm building. Do you recall what gear ratio is in your T2 basher? Thanks!
Re: Ok maybe it is just a tad bit over geared
Posted: Mon Nov 15, 2021 1:01 am
by JosephS
It seems that the consensus is to go brush-less, But that requires me to dump all the electronics. I was trying specifically to make this a lower cost build so I am trying to see if there is a direction where I can drive this without much more into it.
If I got a 3000 Mah Nimh and tamed the gearing would that be about right?
Is there any merit to a brasher with the Titan 12 turn 550 that is used in traxxas trucks? Or are those only happy on Nimh as well?
On the other end would a high turn brushed motor like a 35T crawler motor be just fine in the setup I have now?
Any of these should be less than $20, but even that isn't worth it if I still wind up with a truck that I wind up wrenching on more than driving.
Re: Ok maybe it is just a tad bit over geared
Posted: Mon Nov 15, 2021 1:27 am
by juicedcoupe
The Titan motor doesn't have much merit to it. They are well known for multiple different types of failures.
If you want a good 550 motor, I believe that Team Brood has some options.
The old Kyosho LeMans, Mega, and Mad Science 550's were also good quality. But they might be a little on the slow side compared to what you have.
Re: Ok maybe it is just a tad bit over geared
Posted: Mon Nov 15, 2021 3:04 am
by RC10th
I guess the big question is what sort of speeds will you be happy with? The Titan 550 12T is nothing to write home about as said by juicedcoup, think Traxxas Slash speeds. A proper 12T modified motor would run rings around the 12T Titan.
For general bashing a brushed motor somewhere in the 15 turn to 19 turn range would be a good start. You never mentioned what gearing your currently running so it's hard to tell where your at, but to give you an idea I used to run 18/87 in my T2 back in the brushed days with a 10 turn Reedy modified.
If I were you I'd have a quick look to see if the comm and brushes are burnt (blue), re-solder those connections so they aren't cold joints, and change the gearing to suit. Those motor connectors aren't doing you any favors either. When you go to run the car again pull it in every minute or so and hold the motor, if you can't hang on to it for about 3 - 5 seconds it's too hot. From memory the magnets start to degrade at about 180* Fahrenheit, so it's a good idea to check it for a few battery packs as this will give you a good idea how hot it's getting through a run. Once you know it's good then you won't have to worry about it for a while.
Failing all of that the 550 5.5T motor isn't a
bad choice as it's only rated at 3700kv which wouldn't be too bad on 2 cell. It "should" fit but might be limited on gear choice, and if the motor has a 5mm output shaft you'll have to find either 5mm 48pitch pinions or change over to a 32 pitch pinion and spur.
XLR8 wrote: ↑Mon Nov 15, 2021 12:08 am
I've never ran anything lower that 10.5t but I have this Castle ? motor that's a 4600kV (or maybe it's 5600kV

) that came in some car I got from ebay a while back that I might try in this monster truck I'm building. Do you recall what gear ratio is in your T2 basher? Thanks!
I'd have to double check what KV the 8.0T is but I'm currently running 20/87 with it.
Re: Ok maybe it is just a tad bit over geared
Posted: Mon Nov 15, 2021 10:03 am
by JosephS
RC10th wrote: ↑Mon Nov 15, 2021 3:04 am
I guess the big question is what sort of speeds will you be happy with? The Titan 550 12T is nothing to write home about as said by juicedcoup, think Traxxas Slash speeds. A proper 12T modified motor would run rings around the 12T Titan.
For general bashing a brushed motor somewhere in the 15 turn to 19 turn range would be a good start. You never mentioned what gearing your currently running so it's hard to tell where your at, but to give you an idea I used to run 18/87 in my T2 back in the brushed days with a 10 turn Reedy modified.
If I were you I'd have a quick look to see if the comm and brushes are burnt (blue), re-solder those connections so they aren't cold joints, and change the gearing to suit. Those motor connectors aren't doing you any favors either. When you go to run the car again pull it in every minute or so and hold the motor, if you can't hang on to it for about 3 - 5 seconds it's too hot. From memory the magnets start to degrade at about 180* Fahrenheit, so it's a good idea to check it for a few battery packs as this will give you a good idea how hot it's getting through a run. Once you know it's good then you won't have to worry about it for a while.
Failing all of that the 550 5.5T motor isn't a
bad choice as it's only rated at 3700kv which wouldn't be too bad on 2 cell. It "should" fit but might be limited on gear choice, and if the motor has a 5mm output shaft you'll have to find either 5mm 48pitch pinions or change over to a 32 pitch pinion and spur.
XLR8 wrote: ↑Mon Nov 15, 2021 12:08 am
I've never ran anything lower that 10.5t but I have this Castle ? motor that's a 4600kV (or maybe it's 5600kV

) that came in some car I got from ebay a while back that I might try in this monster truck I'm building. Do you recall what gear ratio is in your T2 basher? Thanks!
I'd have to double check what KV the 8.0T is but I'm currently running 20/87 with it.
It sounds like you raced an even hotter motor than this so I may just need to fix my solder joints and re-gear it. How long was each heat at the time?
I think I am now more concerned about the longer run times being an issue with a brushed motor.
I'm not sure on the actual gear ratio(I just checked it was 19/54), I'll have to pull it and see. The story get a bit dumb because I pulled the stock 87 spur gear when a gear cover i bought for my t2 was rubbing. I pulled the spur and pinion that was on an A stamp 6 gear and everything fit. I was having to run a gear cover because my 48p pinions just weren't staying out on the motor shaft, even with new set screws. Though the 32 pitch pinion stayed right where I put it. I think I have a proper actual T2 cover with a new car I bought. I have a feeling the cover I was sold as a t2 cover, wasn't.
I have no issue with getting some new gears to have compared to everything else that is a low cost option.