Round or D-Shaped Rim for Drifting: Which to Use

What the two rim shapes are

A round rim is a full circle. A D-shaped rim, sometimes called a flat-bottom rim, is the same circle with the bottom section flattened. Both shapes appear on racing wheels; the name of the shape is a stated design detail that many listings print in the title or in the specification list.

The shape is tied to the way a driver holds and turns the wheel. Drifting tends to use large steering angles and crossed hands; GT and Formula racing use smaller steering rotation and a fixed hand position. The rim shape follows that difference, which is why drift-style wheels are round and GT or Formula style wheels are often D-shaped. The close comparison between the two shapes is in D-shaped vs round wheel rims.

The round shape is the original wheel shape and appears on road car wheels, rally wheels and drift wheels. The D-shape is a later design made for race-style cockpits; listings describe it as 'flat bottom' or 'D-cut'. Both words point to the same bottom-flattened shape.

Why drifting calls for a round rim

Drifting asks the driver to hold the car at an angle while counter-steering, which means the wheel regularly turns far beyond the angles used on a race track. At those angles the driver uses the hand-over-hand technique: one hand releases, moves across and regrips on the other side of the wheel while the wheel keeps rotating.

A round rim supports that technique because every point on the circumference is usable. When the wheel is rotated most of a full turn, the hand that started at the bottom may need to grip at the top or sideways. A flat-bottom edge sits at the bottom; when the wheel turns, that flat section moves and interrupts the hand. This is why drift wheels are almost always round.

When a drift car is at full lock, the steering wheel is turned so far that the driver's hands cross. One hand passes over the top of the rim, the other passes under it. A round rim has no gap at the bottom, so the under-passing hand stays in contact. With a flat bottom, the under-passing hand loses its hold and the driver has to re-grip after the flat section has passed. The drift wheel features article covers the other details that drift wheels state, and the racing wheel buying guide compares wheels on stated details.

Why GT and Formula favor a D-shape

GT and Formula racing use much smaller steering angles, and drivers keep their hands at a fixed position on the rim for the whole lap. The flat-bottom edge gives the driver a reference: when the flat section sits at the bottom, the wheel is roughly centered, and the driver can return to that position without looking. It also leaves more room below the rim for the driver's legs in a low seating position.

A wheel that does not need to turn far enough for the hands to cross does not need a full circle. The lower part of the rim is where the legs sit in a GT or Formula cockpit, so a flat bottom is a practical shape. Formula style wheels go further and mount the hands and most of the controls around the upper part of the rim; the Formula style wheel article explains that layout.

The flat bottom also serves as an orientation aid. Drivers of GT and Formula cars sit with the wheel roughly level; when the flat edge is at the bottom, the wheel is centered. During a lap the wheel returns to that position again and again, so the driver can use the flat section to confirm the wheel state without looking at the rim.

Interchangeable rims: one base, several shapes

Wheel bases with a quick release let you change the rim without changing the base. The Fanatec site describes its motorsport-derived quick release as one base that covers every discipline, and lists Formula, GT, Rally and Drift as the disciplines you switch between.

If your plans include drifting and GT racing, a base with an interchangeable rim lets you keep one round rim and one D-shaped rim and match the shape to the discipline. Direct drive bases are the category where this is most common; the direct drive guide compares them on stated torque and features, and the interchangeable rims article explains how a quick release works.

When you compare bases with interchangeable rims, the stated details to read are the drive type, the stated torque, and the quick release system on the base. The shape of the rim is a separate stated detail of the rim you attach. A base without a quick release usually comes with a fixed rim, and the shape of that rim is the one you get in the box.

A single base with several rims raises the total spend, so it suits a buyer who wants to add parts over time. A buyer who wants one wheel in the box and one discipline is better served by a fixed rim in the shape that matches the discipline.

Deciding between round and D-shape

The decision starts with what you plan to drive more often. If drifting is the main use, choose a wheel with a round rim. If GT or Formula racing is the main use, a D-shaped rim is the common choice. If both are on the table, look for a base and rim system where you can switch shapes; the force feedback wheel guide lists round-rim models and the direct drive wheel guide lists bases with interchangeable rims.

The shape is one detail among several. The drive type, the stated torque, the pedals and the platform compatibility all sit in the same list. A wheel with the right shape but a drive type that does not match your plans is not the right wheel; the guides split those categories on stated details.

Many listings state the shape in the title. When the listing does not state it, the maker's product page holds the shape detail; the guides on this site compare racing wheels on stated details, so a missing shape is simply left out. The table below matches a situation to the guide that fits it.

What to pick for your situation

Questions

Is a round rim always better for drifting?

A round rim is the common choice for drifting because every point on the circumference is usable when you steer hand-over-hand. A D-shaped rim has a flat bottom that can interrupt the hand at large steering angles. The maker's product page for a given wheel states which shape it has; see the D-shaped vs round wheel rims article for the close comparison.

Can I drift with a D-shaped rim?

Yes, but the flat bottom sits where the hand would pass when the wheel is turned far. For regular drifting with large angles, a round rim is the more suitable choice. The shape is one stated detail among wheel size, pedals and drive type; the racing wheel guides on this site compare wheels on those details.

Do wheel listings always say whether the rim is round or D-shaped?

Many do: the shape appears in the title or in the specification list. When it is not stated, the maker's product page holds the details. The guides on this site compare racing wheels on stated details, so a missing shape is left out and not guessed.

Are Formula and GT wheels the only ones with D-shaped rims?

D-shaped rims are common on GT and Formula style wheels, but some GT wheels are round. The shape is a design choice, and the discipline decides which one you want. Check the stated details of the wheel before buying; the GT vs Formula wheel rims article goes deeper.

Does a quick release wheel base let me switch rim shapes?

A quick release lets you change the rim on the same base. The Fanatec site describes one base that covers Formula, GT, Rally and Drift disciplines by switching wheels. If you plan to drift and race GT, that setup lets you own one round rim and one D-shape; the direct drive guide compares bases with quick releases.