Tamiya's M-07 Concept Chassis Kit is a 1/10 front-wheel-drive chassis you build yourself, sold without a body, motor or tires.
The included 20T pinion gives a 5.78:1 final drive, and Tamiya's chart runs from 7.22:1 on a 16T pinion to 4.81:1 on a 24T. The chassis builds to a 225 mm or 239 mm wheelbase and is 332 mm long. Start on the 20T with a stock motor, then move up a tooth at a time on an open track, checking the motor temperature after each run.
The kind of vehicle the maker sells it as. It sets what the car is built to do and which cars it is fair to compare it with.
Touring cars are 4WD on-road cars for asphalt and carpet tracks, often raced in classes with fixed motor and battery rules.
The maker does not name a class for this one, so this is the site's judgment from its design.
Drive
Only one axle is driven, the rear on almost every 2WD RC car.
It is lighter and simpler, and it takes more throttle control out of corners.
Build
A kit you build yourself from parts.
Most kits come without motor, ESC, servo, radio and battery, and many without tires or a painted body.
The manual lists what to add.
Scale
The maker's nominal size compared with a full-size vehicle. It works more as a class label than a measurement.
A 1/10 monster truck is far bigger than a 1/10 touring car, so compare length and weight for real size.
This one is 332 mm long.
Part number
The maker's product number for this exact version.
A V2, a new color, or a kit instead of an RTR usually has a different number, and parts can differ between them.
Check it against your box or receipt before ordering parts.
Class
Touringour call
Drive
2WD
Build
Kit
Scale
1/10
Part number
58647
Drivetrain
Pinion
The small gear on the motor shaft. Fewer teeth gear the car shorter: quicker acceleration, lower top speed and a cooler motor. More teeth do the opposite.
On this car one tooth changes the gearing by about 5.0%.
Racers change the pinion to suit the track and the class's motor rules, and often compare setups by rollout rather than tooth count.
Spur
The large gear the pinion drives. A bigger spur with the same pinion gears the car shorter.
Pinion and spur must have the same pitch, or tooth size, to mesh.
Transmission & axle
Every reduction after the spur, multiplied together: transmission, differentials and axle gears.
It is fixed by the design; the gearing you change is the pinion and spur.
Final drive
How many times the motor turns for one turn of the wheels. A higher number is shorter gearing: more acceleration and pulling power, less top speed.
Among 1/10 touring and pan cars in the catalog, the middle half run between 6.5:1 and 8.3:1 on stock gearing; this one is 5.8:1, taller than most.
On-road racers often compare gearing by rollout instead, because tire sizes differ between cars.
Pinion
20TStock
Stock
Spur
37TStock
Stock
Transmission & axle
3.12:1Stock
Stock
Final drive
5.78:1Stock
Stock
Wheels & tires
Tire diameter
The outside diameter of the mounted tire, tread to tread. A taller tire covers more ground each turn, which gears the car taller.
Race tires wear down over a day, and a smaller tire gears the car shorter.
Tire diameter
Not applicable
Power
Motor
Motor KV is the RPM a motor turns per volt with no load.
This vehicle comes without a motor, so there is no stock KV; it depends on the one you fit.
Battery
The highest LiPo cell count the maker rates the electronics for.
This vehicle comes without electronics, so it depends on the ESC and motor you fit.
Motor
Not applicable
Battery
Not applicable
Performance
Theoretical top speed
It needs a motor KV, and this vehicle comes without a motor. Fit one and the calculator works it out from the motor's KV and the gearing.
Theoretical top speed
Not applicable
Size & weight
Length
Overall length as the maker states it, usually with the body fitted.
Useful for comparing real size, since scale labels are loose.
Width
Overall width as the maker states it, usually with the body fitted.
A wider car is more stable in corners and harder to roll over.
Wheelbase
The distance between the front and rear axle centers. A longer wheelbase is steadier at speed and over bumps; a shorter one turns more tightly.
This chassis can be set to more than one wheelbase.
Length
332 mm13.1 inStock
Stock
Width
164 mm6.5 inStock
Stock
Wheelbase
225 or 239mm, 2 settingsStock
Stock
How to read these figures
Stock is as the vehicle ships.
Calculated is worked from the stock figures on this page rather than stored beside them, so the two cannot drift apart.
Not applicable means the vehicle does not come with it, like the motor on a roller or the tires on a race kit, or does not have one, like a KV rating on a brushed motor.
Tamiya prints 'Gear Ratio = 5.78:1 using included 20T pinion gear', with 7.22:1 to 4.81:1 available on separately sold pinions; the Japanese page calls that range nine steps.
The chart's pinions are derived, 16T to 24T: 5.78 x 20 = 115.6, and 115.6/16 = 7.22 and 115.6/24 = 4.82.
The manual's gear table (PDF p. 23) prints 'Spur gear teeth (37T) / Pinion gear teeth x 3.1221', which gives the kit spur and the ratio after it.