Motor Is To Hot To Touch Help !!!!!

[daffy1]

hi am new to rc cars so can some one help me,

I have just ran a LRP 3600 battery through my TT-01 using a ripmax xtra no-limit esc and a LRP GT-3 TURBO 14x2 motor.When i took the shell off and touched the motor it was to hot to touch.
I am very happy with the speed of the car not just a bit worried about how hot it was.
I think i could be the gearing i am using 61t spur gear and a 19t pinion gear i know this no good but in the info i got with motor it reads touring car 7.4:1
dont really understand this.

THANKS FOR ANY HELP
LEE.

[tq_racing]

sounds like the gearing is the problem, Im not to good with onroad gearing (or offroad for that matter) I hope some one who knows what their talking about can help you out.

[702nitro]

hi am new to rc cars so can some one help me,

I have just ran a LRP 3600 battery through my TT-01 using a ripmax xtra no-limit esc and a LRP GT-3 TURBO 14x2 motor.When i took the shell off and touched the motor it was to hot to touch.
I am very happy with the speed of the car not just a bit worried about how hot it was.
I think i could be the gearing i am using 61t spur gear and a 19t pinion gear i know this no good but in the info i got with motor it reads touring car 7.4:1
dont really understand this.

THANKS FOR ANY HELP
LEE.

The motor definitely running too hot. If you have a temp gun the motor temp should be withing the ranges of 210 - 220 deg F to be on the safe side.

Is the timing on the motor advanced? If so, retard the timing a few degrees.
You gearing can also be the problem. Try increasing the Spur, this will gear it more towards the torque side.

[daffy1]

ok was going to buy a motor heatsink but how well do these really work ?? . and what size spur an pinnion should i use.

[702nitro]

ok was going to buy a motor heatsink but how well do these really work ?? . and what size spur an pinnion should i use.

You can either keep the current spur and drop down a pinion
Or, Keep pinion but increase Spur.

The heatsink it should help out. Remember heat is a motor and esc nemesis

[Prelude14WRX]

Try the metal motor mount hop-up by Tamiya...it helps take away the heat better than plastic. If you don't have bearings...that might solve your problems right there. Even my kit silver can motor gets really hot.....maybe you can rig up a computer fan hooked up to a 9V.

Here's a question....does your car accelerate really great and just spin its tires.....or does it take forever to get going, but is really fast?

[highroller]

The 7.4:1 is the calculated rollout that is suggested with the motor. I would need the transmission ratio, (2.4, 2.25 whatever) plus size of the tires to formulate what pinion size brings you close to a 7.4:1.

[highroller]

Checked Tamiya's website, from what I can gather they don't pinions below 21 teeth. But the tt01 chassis has a 2.60 transmission ratio so to find what pinion you need to get close to the recommended 7.4 range would be a 21 tooth pinion with the 61 spur it would be 7.55.
7.4 x 61 divided by 21 = 7.5523.
Something else must be causing the motor to work extra hard, with your present gearing you would be undergeared. Put car on a flat surface with motor, battery installed and push it across floor - if it doesn't go very far there is something causing drag or too tight. If you have to, take car apart starting with the front gearbox, then rear gearbox and also check for wear.
Inspect the motor itself, look for discoloration to brushes, comm and even motor wires. Motor parts should be a copper color if it they seemed to have a blackish color then possibly gearing and drivetrain drag is a culprit. Since the gears from Tamiya a metric (usually) it may be an advantage to swap to a standard spur and would also be easier to purchase the pinions in a wider variety. Second I also increase the spur size to maybe a 72 to 78 if possibly to allow the motor to run a little smoothly. While the Tamiya gears (spur & pinions) work okay for Tamiya motors - other motors usually are a bit more powerfulor develop a much different power band that Tamiya type motors.

[daffy1]

PRELUDE 14 WRX
I have already changed the bearings for metal ones and have the metal motor mount.About the speed it takes off like a rocket !!! But also gets as hot as one !!!!!


HIGH ROLLER
Thanks for all the info i will thy a lower pinnion and higher spur if i can find somewere that will sell them to fit a TT-01.

[Prelude14WRX]

PRELUDE 14 WRX
I have already changed the bearings for metal ones and have the metal motor mount.About the speed it takes off like a rocket !!! But also gets as hot as one !!!!!


HIGH ROLLER
Thanks for all the info i will thy a lower pinnion and higher spur if i can find somewere that will sell them to fit a TT-01.

Under gearing your car(really fast acceleration) can also cause a motor to work extra hard. I would buy the 21T/22T pinion set and the 23T/24T set(but you can't use the 24T). Just try different pinion gears and see what works best.

With the spur gear....you can't go to the store and buy any ol' spur gear. It has to be tamiya. The biggest spur gear is the one that is on your car right now.....the spur gears only get smaller if you want a new one.

[highroller]

Check Kimbrough, Robinson, RPM websites to see if they make a spur gear and adaptor for the TT01 vehicles.
I would first try gearing the motor differently to see if that helps. Since many touring car chassis retricts airflow, your next addition could be a motor heatsink or motor cooling fan or both. Also check the mesh of the spur and pinion to make sure they aren't too tight (close).

[daffy1]

Thanks chaps for all the info i will try a 22t pinnion this forum is so much help my LHS is a model zone and they are not really much help all they are interested in is trying to sell you the most expensive pice of new kit they have just got in.

[Prime78]

a littal sugestion to keep your mouter running cooled is put some small fans on it yes it will run your batterys down a littal faster about 1 min less run time or so but your moter will run cooler and will inturn give you more power once i remember wher i saw how to add the fans to your moter too cool them off i will post it hear ok hope this helps you

[Prelude14WRX]

Check Kimbrough, Robinson, RPM websites to see if they make a spur gear and adaptor for the TT01 vehicles.
I would first try gearing the motor differently to see if that helps. Since many touring car chassis retricts airflow, your next addition could be a motor heatsink or motor cooling fan or both. Also check the mesh of the spur and pinion to make sure they aren't too tight (close).

The gear mesh is set at the factory for 19, 20, 21, and 22T spur gears with the stock spur gear. Gear mesh wont be an issue here...

[highroller]

If the gear is not true to start with, then the mesh will not be set properly.
The mounting plate while it will fit other motors, the alignment may be slightly off, not to say that is the cause but something I encountered with other Tamiya kits. Once motor is installed in vehicle, screws are tighten try rotating the spur with thumb until spur has complete several rotations. See if you can determine if the gap between the spur and pinion teeth remains the same of changes - where one area the space may be closer or farther away. The other method is to cut a piece of paper to the width of spur and let the paper feed it way through - if tears appear then mesh is too tight our gear is out of round.

[tom losi]

yeah this is the same motor i have problems with. is this motor ok? does anyone else use this motor, and it doesn't get hot?

[tadium54]

check for binding in the drivetrain, proper mesh, or maybe something thats stuck in the can of the motor

[daffy1]

ok i have just put a 23t pinion on now ran it for about 10 mins and the motor started to smoke and melt the chassis.what else can i do or is this motor just a cheap crap

[NotWalkinBlind]

If you just tried the 23T pinion and you're still using the 61T spur, you made your problem worse since you began with a 19T pinion... 702 said "go down a pinion" and I believe that should help you out if you're not gonna change the spur to more teeth... that would mean going to an 18T pinion.

Did you do ALL this (that HighRoller suggested) yet? It's good advice.
Something else must be causing the motor to work extra hard, with your present gearing you would be undergeared. Put car on a flat surface with motor, battery installed and push it across floor - if it doesn't go very far there is something causing drag or too tight. If you have to, take car apart starting with the front gearbox, then rear gearbox and also check for wear.

[daffy1]

yea have done everything highroller said think i need to buy a better motor i was using a tamiya super stock rz motor before and had no problems and i think it was faster than the LRP GT-3 TURBO 14X2 even though the RZ WAS ONLY A 23 T

[NotWalkinBlind]

Yeah, a 14x2 is a pretty hot wind, so you probably should try one that is not so wild.

If that doesn't help, you can always assist the cooling by cutting a 1.5" wide by .75" tall hole in the bottom of the windshield right in front of where the motor is, then tape a [ shaped "air channel" made of index card paper inside the windshield (facing down) kinda like this: /********\ and leading all the way back to the top of the motor to direct air onto the ESC and motor.

A heat sink is also good... can't remember if you said you are using one already.

Here's a bush-league sketch of the air channel. It doesn't have to fit tight up against the motor and heat sink. You would just attach it to the inside of the windshield with clear tape. If you need a better sketch than this, PM me your email address and I'll do something better and send it to you in the next coupla days.

http://img.photobucket.com/albums/v134/NotWalkinBlind/ProtoDodge.jpg

[RrR]

I don't think I see this posted yet so here I go.. How long did you run the car? How hard did you run the car? My motors will get hot if I run full throttle till my packs are gone. But my car is a E-Maxx and I have a large ruff hilly yard.

[daffy1]

ran it quite hard for about 10 mins on tarmac maybe a bit longer but the car started to glitch and go out of control then it would be ok for a couple of mins then would start to glitch again i have got another motor so will try this out as the super stock rz motor was fine.

[highroller]

Based on suggested gearing you gave, the pinion should have been a 21 tooth and to me that seemed a tad high. Now based on what happened, motor probably may need a rebuild - or just clean up the comm -replace brushes. Remove the brush springs keep them in order they were installed (pos or neg terminal - some springs are taylored to different tensions), next pull out each brush looking for extreme wear or discoloration - angle the motor so you can look at comm, look at wire bundle if it looks bluish/black the motor was extremely over geared. You can get a better look at wear by disassembling motor - first use a permanate mark - color one endbell screw, then place a mark on motor can (this help in reassembling motor so it set at factory timing and will rotate in right direction - unless endbell is fixed), once endbell is remove keep the shims in correct order (check endbell and inside of motor where output shaft extends out). With armature out you can inspect it more closely. If possible to get someone to true comm - replace brushes and springs, to bring back some of the power. Right now motor will probably run iratic - stop and go - or run for a short period at good spend then slow as if battery was dumping.
There is a big difference in power motors make and the need for gearing based on the presumed power band. Stock 27 turn would be geared based a little differently while 19-23 turn motors are sometimes geared the same as stock or slightly higher(even though they have less winds the power band is similar to some 27t stockers). With modifieds assume that starting point will normally be 3-4 teeth lower (smaller) than the ideal gearing for other motors.
The 23turn would have run better with the 23tooth pinion while the 14turn didn't because it was overgeared. Whenever you are using a motor and not sure of it's gearing range (size pinion or spur) even for bashing - start with the motor or vehicle manufacturer suggested gearing. Run only in short bursts of 30seconds to a minute. An experience person can normally tell right off when motor is somewhere in a good range (good acceleration and speed) while some should use the temperature of motor (how hot it feels) to tell when speed or acceleration can be used as comparison method. The 14turn when properly geared should have accelerated quicker - and been up to top speed a lot quicker than the kit motor.