For smooth indoor cornering, the geometry that usually makes life easiest is a compact, well-balanced true X frame with a relatively short wheelbase. The reason is simple: when the motors are positioned evenly around the center, the quad tends to pitch and roll more predictably. That matters a lot indoors, where you’re constantly making small corrections and trying not to bounce off gates, walls, or furniture. A true X gives you a more symmetrical feel than a stretched X, which often feels a little better for forward speed and straight-line stability, but less natural when you want fast, tight direction changes.
If your priority is smoothness rather than pure top speed, the weight distribution matters just as much as the shape. A frame with the batteries and electronics centered tightly around the middle will feel more planted in corners. Less mass hanging far out on the arms means the quad changes direction with less delay. Indoors, that can make a bigger difference than whether the frame is technically a little more X-shaped or slightly stretched.
A stretched X can still work indoors if you like a more locked-in front-to-back feel, but it usually shines more on tracks with longer straights. In cramped rooms, it can feel like it wants to push through the turn instead of snapping through it. That’s not always bad, but if you’re trying to thread gates or carve around posts at low speed, a true X is usually easier to control. A plus frame is less common for racing now, and I would not pick it first for this use unless you have a very specific reason.
Prop size and motor placement also play a role. Smaller props, like 3-inch or 2.5-inch setups, often feel less twitchy indoors and make cornering cleaner because they are easier to modulate. A large, aggressive setup with a high pitch prop can feel jerky in tight spaces, even on a good frame. If you are using a larger indoor build, the frame geometry matters even more, because every bit of extra arm length increases the effect of inertia when you turn.
For tuning, you can make almost any decent frame corner smoother by lowering rates a bit, softening the center of your throttle curve, and making sure the quad is not over-propped or over-motored for the space. But if you are choosing the frame first, my practical recommendation is a lightweight true X with short arms, centered battery mounting, and enough prop clearance for precise control rather than maximum speed. That combination tends to feel the most natural in tight indoor turns.
If you want the shortest answer: for smooth indoor cornering, pick a compact true X first, then tune rates and prop choice around that. A stretched X is fine if you fly faster lines, but true X usually gives better balance and easier corner control in small spaces.
