Motor Levels

As you look through these rules you will see the following names used for motors. Please refer to these pages for definitions and clarifications of motor levels. Any variance of these rules will be listed in the class rules.
Stock:
Are to be motors that are R/C motors with non-adjustable end bells. These motors will be labeled as ROAR motors. Rebuildable stock motors will have an identification mark on the can and armature. These marks will either be the ROAR name or the manufacturers name along with the number 27. You can not tamper with, in any way, the timing adjustments, which include the use of cut brushes that will affect the timing. Ball bearings, external magnets, internal Cobalt or neodymium magnets are not permitted. You are allowed to machine the commutator with a comm. stick or a stock comm. lathe only. No opening of a motor with a staked end bell. You may disassemble rebuildable stock motor for maintenance. Other than machining the commutator you may not alter rebuildable motors. This includes swapping end bells, cans or armatures. You are allowed to change springs and brushes in the motor. The end bell must have a bushing.

Econo Modified:
Are to be motors that are readily available R/C motors. These shall be 05 can size modified motors. These may have ball bearings and adjustable timing. External magnets, internal Cobalt or neodymium magnets are not permitted. You are allowed to machine the commutator with a comm. stick or with a comm. lathe. The 4.5mm X 5mm brush and hood, “readily available R/C motor accessory” also known as the “P-94” brush hoods may be used. Motors from Stock may also be used.

Sport Modified:
Are to be motors that are readily available R/C motors. These shall be 05 can size motors with a minimum of 17 turn armature. These may have ball bearings and adjustable timing. External magnets, internal Cobalt or neodymium magnets are not permitted. Motors are to be a brushed motor. You are allowed to machine the commutator with a comm. stick or with a comm. lathe. The 4.5mm X 5mm brush and hood, “readily available R/C motor accessory” also known as the “P-94” brush hoods may be used. Motors from Stock may also be used.

Modified:
Are to be motors that are R/C motors. This level motor may have an adjustable end bell. This level of motors are allowed to have adjustable timing, modified or cut brushes, and ball bearings. The commutator is allowed to be machined. The output shaft is allowed to be shortened and/or have a flat spot machined in it. Drilling holes in the end-bells is allowed in order to cool motor. Maximum diameter is 2 ¼ inches. Maximum length is 3 ½ inches. The Astroflight Pullmaster I and Pullmaster IV are allowed in this level until further notice. Motors from Stock, and Econo Mod are allowed. Brushless motors are allowed at this level.

Open II:
These motors must be approved by the NR/CTPA. These are to be motors that are R/C motors with an adjustable end-bell. Maximum total wattage of all motors must not exceed 3100 watts. This level of motors are allowed to have adjustable timing, modified or cut brushes, and ball bearings. The commutator is allowed to be machined. The output shaft is allowed to be shortened and/or have a flat spot machined in it. Drilling holes in the end-bells is allowed in order to cool motor. Maximum diameter is 2 ¼ inches. Maximum length is 3 ½ inches. At print time the list of approved motors is Astroflight Pullmaster III, and IV, Astroflight 25, 40 and 60, Astroflight Sport, Finedesign, and Graupner.