I never clean the tracktion tires per say but I do clean all my wheel rims from time to time.
Place your engine top down in a soft cradel then take a Q-tip, or soft cloth dipped in Goof-Off, do not soak the cloth so as to have the cleaner run down into the engine. Now let the engine run slowly with the wheels spinning under your cloth. Do this one wheel at a time.
After the wheels dry place a little drop of Super Glue under your tires. Using a small flat face screwdriver to smooth out the glue as you let the engine run as stated above will provide you alot longer life to all of your tires.
If something on the track causes the tire to get cut or stretch out then it is time to toss it.