Once your car is assembled, if may run erratically or not at all. So here are some tips to figure out what is wrong.


- The car does not run when current is applied

Using wires connected to a 12-volt DC power supply, Apply direct electrical contact to the braided contacts of the car to make sure that  the car and not the track is causing the problem. If the car does not run, proceed to the next step.

Apply current directly to the motor first to make sure that the motor functions properly. You can use the wires from your power supply applied to the two motor terminals. If the motor runs, check that the motor has been installed properly. The TSR sticker must face the REAR of the car. Check that the negative contact wire is applying proper pressure on the negative lead on the motor when the motor is pushed in place. Check that the positive contact wire is effectively connecting the motor's can. Check that both contact wires are firmly set in their retaining tabs. If any part of the contact wires touch the steel pan, it will cause a short and the motor will not run. Terminal heat damage to the chassis and contact wires may also result from improper installation of the contact wires. Check that the braided contacts are sitting on top of the contact wires below the guide post, and that any part of the braided contacts are not contacting the steel pan or each other. 


-The car runs poorly

Remove the motor and check that the rear axle turns freely and is not binding in any way. Is so, install the motor in its proper location. Make sure that it sits flat. If the rear axle is still not turning freely, you may slightly twist the axle inside the axle bearings to line things up. The chassis plastic is designed for such an alignment method. Optimum axle side clearance is .005".

Check that the gears are the proper combination of ratios: see chart below:

Pinion               Spur gear

11-tooth              48-tooth

12-tooth              47-tooth

13-tooth              46-tooth

14-tooth              45-tooth

Any other combination may not operate properly. However, it is actually possible to "jump" a tooth by using a 1-tooth larger pinion with the corresponding gears. Example: 12-48 will work for serious and intense racing, making the mesh tighter. This is only possible when using the metal gears, do not attempt this with the home-racing plastic gears. Do not attempt to use any other gears than the TSR-manufactured units or specially designed NSR (Italy) units, as the wrong combination may damage the motor.

Make sure that the gear mesh is smooth, with no damage to either gear. Replace any damaged gear immediately.

Check that the front wheels turn freely on the front axle, and lubricate with TSR recommended lubricant.

Check that the body or drivers compartment is not interfering in any way with the front or rear wheels or any part of the chassis. Check that the steel pan is not bent. Check that the braided contacts are set FLAT with a slight down curving at their end. ONLY THE ENDS of the strands should contact the track rails, NEVER their center part. NEVER curve the braided contacts in a convex manner, as the car will operate poorly and cause excessive wear of the braided contacts.

Post inquiring messages on the TSR Forum if you have any unresolved issues.

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