|
Professor Motor is proud to offer the following technical information for chassis tuning. Lower gear ratios (higher ratio numbers) give your car faster acceleration out of a corner, higher gear ratios (lower ratio numbers) gives your car faster top speed. The final selection of a gear ratio is dependent on many factors and is by nature a compromise in trying to achieve the best possible performance. The ratio chart is sorted in decreasing order of the resultant ratios.
Application Note : Not all of these ratios may be suitable for every application since tire size and the resulting ground clearance will limit the possible combinations of gears that can be used. |
Professor Motor Sidewinder (Spur) Axle Gear / Gear Sizefor Fly, GB Track, TSRF, Scalextric & Slot.it HRS I Chassis Applications |
Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
PMTR1106 / 47 tooth spur gear (sidewinder) |
PMTR1080 / 12 tooth pinion gear (sidewinder) |
3.92 : 1 |
PMTR1089 / 46 tooth spur gear (sidewinder) |
PMTR1103 / 13 tooth pinion gear (sidewinder) |
3.54 : 1 |
PMTR1088 / 45 tooth spur gear (sidewinder) |
PMTR1104 / 14 tooth pinion gear (sidewinder) |
3.21 : 1 |
PMTR1087 / 44 tooth spur gear (sidewinder) |
PMTR1105 / 15 tooth pinion gear (sidewinder) |
2.93 : 1 |
Professor Motor Sidewinder (Spur) Axle Gear / Gear Sizefor Pro Slot & Slot.it HRS II Chassis Applications |
Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
PMTR1106 / 47 tooth spur gear (sidewinder) |
PMTR1078 / 10 tooth pinion gear (sidewinder) |
4.70 : 1 |
PMTR1089 / 46 tooth spur gear (sidewinder) |
PMTR1079 / 11 tooth pinion gear (sidewinder) |
4.18 : 1 |
PMTR1088 / 45 tooth spur gear (sidewinder) |
PMTR1080 / 12 tooth pinion gear (sidewinder) |
3.75 : 1 |
PMTR1087 / 44 tooth spur gear (sidewinder) |
PMTR1103 / 13 tooth pinion gear (sidewinder) |
3.38 : 1 |
Slot.it Inline (Crown) Axle Gear / Gear Size |
Slot.it or Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
SIGI30AL /SIGI30BZ /SIGO30BZ / 30 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.75 : 1 |
SIGI29AL /SIGI29BZ /SIGO29BZ / 29 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.63 : 1 |
SIGI28AL /SIGI28BZ /SIGO28BZ / 28 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.50 : 1 |
SIGI27AL /SIGI27BZ /SIGO27BZ / 27 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.38 : 1 |
SIGI30AL /SIGI30BZ /SIGO30BZ / 30 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
3.33 : 1 |
SIGI26AL /SIGI26BZ /SIGO26BZ / 26 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.25 : 1 |
SIGI29AL /SIGI29BZ /SIGO29BZ / 29 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
3.22 : 1 |
SIGI25AL /SIGI25BZ /SIGO25BZ / 25 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.13 : 1 |
SIGI28AL /SIGI28BZ /SIGO28BZ / 28 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
3.11 : 1 |
SIGI30AL /SIGI30BZ /SIGO30BZ / 30 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
3.00 : 1 |
SIGI27AL /SIGI27BZ /SIGO27BZ / 27 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
3.00 : 1 |
SIGI24AL /SIGI24BZ /SIGO24BZ / 24 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
3.00 : 1 |
SIGI29AL /SIGI29BZ /SIGO29BZ / 29 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.90 : 1 |
SIGI26AL /SIGI26BZ /SIGO26BZ / 26 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
2.89 : 1 |
SIGI23AL /SIGI23BZ /SIGO23BZ / 23 tooth crown gear (inline) |
SIPI08 / 8 tooth pinion gear (inline) |
2.88 : 1 |
SIGI28AL /SIGI28BZ /SIGO28BZ / 28 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.80 : 1 |
SIGI25AL /SIGI25BZ /SIGO25BZ / 25 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
2.78 : 1 |
SIGI30AL /SIGI30BZ /SIGO30BZ / 30 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.73 : 1 |
SIGI27AL /SIGI27BZ /SIGO27BZ / 27 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.70 : 1 |
SIGI24AL /SIGI24BZ /SIGO24BZ / 24 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
2.67 : 1 |
SIGI29AL /SIGI29BZ /SIGO29BZ / 29 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.64 : 1 |
SIGI26AL /SIGI26BZ /SIGO26BZ / 26 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.60 : 1 |
SIGI23AL /SIGI23BZ /SIGO23BZ / 23 tooth crown gear (inline) |
PMTR1066 or SIPI09 / 9 tooth pinion gear (inline) |
2.56 : 1 |
SIGI28AL /SIGI28BZ /SIGO28BZ / 28 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.55 : 1 |
SIGI25AL /SIGI25BZ /SIGO25BZ / 25 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.50 : 1 |
SIGI27AL /SIGI27BZ /SIGO27BZ / 27 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.45 : 1 |
SIGI24AL /SIGI24BZ /SIGO24BZ / 24 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.40 : 1 |
SIGI26AL /SIGI26BZ /SIGO26BZ / 26 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.36 : 1 |
SIGI23AL /SIGI23BZ /SIGO23BZ / 23 tooth crown gear (inline) |
SIPI10 / 10 tooth pinion gear (inline) |
2.30 : 1 |
SIGI25AL /SIGI25BZ /SIGO25BZ / 25 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.27 : 1 |
SIGI24AL /SIGI24BZ /SIGO24BZ / 24 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.18 : 1 |
SIGI23AL /SIGI23BZ /SIGO23BZ / 23 tooth crown gear (inline) |
SIPI11 / 11 tooth pinion gear (inline) |
2.09 : 1 |
Slot.it Sidewinder (Spur) Axle Gear / Gear Sizefor Fly, GB Track, Scalextric & Slot.it HRS I Chassis Applications |
Slot.it or Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
SIGS03 / 38 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.80 : 1 |
SIGS02 / 36 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.60 : 1 |
SIGS03 / 38 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.45 : 1 |
SIGS01 / 34 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.40 : 1 |
SIGS02 / 36 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.27 : 1 |
SIGS03 / 38 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
3.17 : 1 |
SIGS01 / 34 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.09 : 1 |
SIGS02 / 36 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
3.00 : 1 |
SIGS03 / 38 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.92 : 1 |
SIGS01 / 34 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.83 : 1 |
SIGS02 / 36 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.77 : 1 |
SIGS01 / 34 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.62 : 1 |
Slot.it Sidewinder (Spur) Axle Gear / Gear Sizefor Pro Slot & Slot.it HRS II Chassis Applications |
Slot.it or Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
SIGS06 / 36 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.60 : 1 |
SIGS05 / 34 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.40 : 1 |
SIGS06 / 36 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.27 : 1 |
SIGS04 / 32 tooth spur gear (sidewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.20 : 1 |
SIGS05 / 34 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.09 : 1 |
SIGS06 / 36 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
3.00 : 1 |
SIGS04 / 32 tooth spur gear (sidewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
2.91 : 1 |
SIGS04 / 32 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.46 : 1 |
SIGS05 / 34 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.83 : 1 |
SIGS06 / 36 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.77 : 1 |
SIGS04 / 32 tooth spur gear (sidewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.67 : 1 |
SIGS05 / 34 tooth spur gear (sidewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.62 : 1 |
Slot.it ANGLEWINDER Axle Gear / Gear Sizefor Pro Slot & Slot.it HRS II Chassis Applications |
Slot.it or Professor Motor Pinion Gear / Gear Size |
Gear Ratio |
SIGA36 / 36 tooth spur gear (anglewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.60 : 1 |
SIGA34 / 34 tooth spur gear (anglewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.40 : 1 |
SIGA36 / 36 tooth spur gear (anglewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.27 : 1 |
SIGA32 / 32 tooth spur gear (anglewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.20 : 1 |
SIGA34 / 34 tooth spur gear (anglewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
3.09 : 1 |
SIGA36 / 36 tooth spur gear (anglewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
3.00 : 1 |
SIGA30 / 30 tooth spur gear (anglewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
3.00 : 1 |
SIGA32 / 32 tooth spur gear (anglewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
2.91 : 1 |
SIGA34 / 34 tooth spur gear (anglewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.83 : 1 |
SIGA28 / 28 tooth spur gear (anglewinder) |
SIPS10 / 10 tooth pinion gear (sidewinder) |
2.80 : 1 |
SIGA36 / 36 tooth spur gear (anglewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.77 : 1 |
SIGA30 / 30 tooth spur gear (anglewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
2.73 : 1 |
SIGA32 / 32 tooth spur gear (anglewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.67 : 1 |
SIGA34 / 34 tooth spur gear (anglewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.62 : 1 |
SIGA28 / 28 tooth spur gear (anglewinder) |
PMTR1068 or SIPS11 / 11 tooth pinion gear (sidewinder) |
2.55 : 1 |
SIGA30 / 30 tooth spur gear (anglewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.50 : 1 |
SIGA32 / 32 tooth spur gear (anglewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.46 : 1 |
SIGA28 / 28 tooth spur gear (anglewinder) |
SIPS12 / 12 tooth pinion gear (sidewinder) |
2.33 : 1 |
SIGA30 / 30 tooth spur gear (anglewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.31 : 1 |
SIGA28 / 28 tooth spur gear (anglewinder) |
SIPS13 / 13 tooth pinion gear (sidewinder) |
2.15 : 1 |
TSRF Sidewinder (Spur) Axle Gear / Gear Sizefor Fly, GB Track, TSRF, Scalextric & Slot.it HRS I Chassis Applications |
TSRF Motor Pinion Gear / Gear Size |
Gear Ratio |
THPR48 / 48 tooth spur gear (sidewinder) |
11 tooth pinion gear (sidewinder) |
4.36 : 1 |
THPR47 / 47 tooth spur gear (sidewinder) |
12 tooth pinion gear (sidewinder) |
3.92 : 1 |
THPR46 / 46 tooth spur gear (sidewinder) |
13 tooth pinion gear (sidewinder) |
3.54 : 1 |
THPR45 / 45 tooth spur gear (sidewinder) |
14 tooth pinion gear (sidewinder) |
3.21: 1 |