The track width is going to change either way but imperceptibly so. Don't sweat it.

As new in TC, I have a question.

If you need more top speed on the strait, how do you know whether to go up a tooth or more in gearing or to increase some of the timing options in the speedo?

My son runs a 418 in kit setup, FDR gearing in the 8 region (according to table in manual to the 6.5T LRP X20 motor fitted), LRP Flow speedo in default settings.

Well, how do you know how to gain more top speed, play with gearing, speedo timing settings or both?

You could use Tamiya 51443, Never had problems in Stock with them on 417, 417X and TB EVO 5 MS. Replaced them every 4 - 5 races.

Andre

Well, I actually have a pair of those. Thought they would be minced by the dogbones driving modified.

Maybe I could give them a try.

Only catch is that they the plastic cups are actually not much cheaper than the steel ones, but the plastic cups will probably not wear the pins on the dogbones, saving the shaft.

Don't forget the alu parts ! Tamiya 9804389

Andre

Ahh, OK, I need those also. Thanks!

The plastic ones fail spectacularly if you make incidental contact.

Steel only please.

Never had one failing in 3 years of driving 417 and 417X, despite having 4 broken C-hubs during Indoor race with 10T sensorless Carson motor.

Andre

I broke one in about twenty laps. Never broke a C hub.

Stock (17.5T / 13.5T) or Modified ?

13.5. Brushed against a slow moving car who turned into me. Didn't even stop. Car looked fine, but had a massive pull to the right. Pulled off and found it.

All of the above plus timing on the motor. And a better motor. And a better battery (some will argue there's some black magic that gives some .0000001 sec a lap or some such). And so on.

Anyway. All that motor timing will help but at the expense of torque (i.e. acceleration) for a given gearing. So will do gearing changes. But you already knew that. The advantage with dynamic timing is that you can decide by using the speedo settings when it kicks in. That way, you can have little timing applied at low revs to use the potential of the torque and once the revs build up you can have more timing added on.

Either way, watch motor temperatures.

Some motors can be geared to high heaven, others not so much. Hacker motors of the past had such huge torque, you'd run out of room to move the motor before you reached their peak.

What to change depends in principle on the track.

But.

Ideally, you should find the motor timing where it's at its best efficiency (not highest torque or RPM), find the optimal gear ratio for that (i.e. so it gives strong acceleration) and then add ESC timing and adjust when/how (delay/ramp) that kicks in.

Thanks for the tips, I will work ahead in that order, motor timing, gearing and then finetune with esc settings.

That gear is too short
Unless you are running on a tiny indoor track

8:1 is about right for a 4-5t motor
Gear up, try around 6.5 to 7:1 for a 150' straight
Leave timing at default on motor, use Flow timing to fine tune how hard you want it to hit

temp at 4m