mod motors in tc3
 

whats the proper pinion/spur for a 12 x2 motor

RE: mod motors in tc3
 

[link=http://www.rcuniverse.com/community/gearwizard.cfm]Skrappy's gear calculator [/link] will point you in the right direction. Put in the number of teeth on your spur gear and then try different pinions until the rollout is as close as you can get to 1. Higher than 1 is more speed - lower is more acceleration. Be careful of gearing too high - you may overheat and damage the motor and maybe the ESC too. Always check the motor temp regularly at first whenever you change gearing - you don't want a meltdown.

RE: mod motors in tc3
 

Ideally you should be calculating the spur/pinion figs on the final ratio.
If your are using 48pitch gears (i.e if your spur is the original one that will be 48 pitch with 72 teeth), then ideally go for a 22 or 23 pinion.

RE: mod motors in tc3
 

What do u mean with "48 pitch"?

RE: mod motors in tc3
 

48 pitch is the refers to the number of teeth per unit length. In electric there are either 48pitch or 64pitch, the latter having more teeth per unit length. In the original box the tc3 comes with a 72 tooth (48 pitch) spur gear.

RE: mod motors in tc3
 

Unit lenght is "inches" right? So, for example, on a gear with a circumference 2 inches lenght there are 92 or 128 theet?

RE: mod motors in tc3
 

ya

RE: mod motors in tc3
 

i tried 22/78 with a 12 double and it burnt up in less than 5 min of practice. i also tried 26/72 with a 17 double it also burnt up,wonder if its the motors.

RE: mod motors in tc3
 

Did you mean 22/72 for the 12X2 motor? That is the recommendation in the TC3 tuning guide that Associated publishes but every motor is different. Assuming the diameter of your tires is about 2.5 inches (I just measured mine - they are 24mm slicks on standard touring car rims) 23/72 should give you a total rollout of 1.004 - the best balance of acceleration and top end.

The trick is to understand what is causing the overheating. If the motors need the comm turned that will create extra resistance which will cause them to overheat (and lose both acceleration and RPMs). If you are geared too high (if the car is never reaching maximum RPM even in the longest straight stretch) the motor will be drawing almost maximum current all of the time and that will cause heat. If you are geared too low (you reach top RPMs right away out of the corner and them just stay at max motor speed for the whole straightaway) you will generate heat in the bearings and the commutator.

Bashing is actually harder on a motor than racing depending on how you do it. When you are racing there are straightaways but there are also low and medium speed corners and braking areas where the motor gets to cool. When you go bashing in a big flat parking lot there is a tendency to hold the throttle wide open all of the time and just steer. That is a worst case condition for an electric motor. You can gear down (smaller pinion) to offset this but you cost yourself top speed.

Are you using a motor heatsink? Associated makes a nice [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXTG84&P=R]heatsink[/link] and [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXSG33&P=R]motor clamp[/link] that will help with motor heat dissipation. You can also get a small [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXKKN0&P=R]fan[/link] and mount it to blow on the motor and ESC to help keep them cool. l hope this helps.

RE: mod motors in tc3
 

my bad 22/72, both motors were brand new, and my drivetrain is very slick so i cant see why that happend.i have a new reedy mod 12x2 but im not sure how to gear it

RE: mod motors in tc3
 

As I said above 22/72 is the recommendation from Associated and 23/72 is the result from Skrappy's gear calculator for a TC3 if you are running standard touring car slicks. Also make sure you don't mesh the gears too tight when you install the motor. If it still gets hot try the above things to figure out the source - get back to us if you still have troubles.