How to Choose Tires for Incision KMC 1.9 KM720 Roswell Wheels

Quick answer

Choose any 1.9-inch tire with a bead diameter that matches the KM720 wheel's outer beadlock ring, then match the tire height and compound to your terrain. If you are unsure, start with a 4.5 to 4.75-inch tall tire in a medium-soft compound and a closed-cell foam. The 1.9 Spyder Beadlock ring is the correct replacement if you damage a ring, but it does not fit every Vanquish wheel.

The Incision KMC 1.9 KM720 Roswell wheel is a scale beadlock, not a glue-on rim. That changes tire buying from a simple diameter check into a bead-seat and ring-compatibility decision. Buy the wrong bead profile and the tire will not seal, no matter how good the rubber is.

This guide gives you concrete rules for picking tires for 1.9 wheels on KM720 Roswell rims. You will see how bead diameter, tire height, compound, and foam interact, plus which Vanquish hardware and accessories actually help when you are swapping tires or rebuilding shocks between runs.

Beadlock fit comes before tread pattern

A 1.9 wheel size tells you the rim diameter, not the bead shape. The KM720 Roswell uses a bolt-on outer beadlock ring, so the tire bead must sit flat between the wheel and the ring. Most 1.9 scale crawler tires use a standard bead profile, but some older or budget tires have thicker beads that will not seat cleanly.

Test-fit before you fully tighten the ring. If the bead bulges out or the ring will not sit flush, stop and try a different tire. Forcing the ring down can damage the wheel or strip hardware. This is also where a proper nut driver tip saves time, because you will be running the same screws in and out several times during a tire swap.

• Dry-fit the tire on the wheel with no foam first to check bead seating.
• If the bead will not sit flat, the tire is not compatible with this wheel.
• Use the correct hex size driver to avoid rounding the beadlock hardware.

Match tire height to your body and gearing

On a scale crawler, tire height changes both ground clearance and effective gearing. A taller tire raises the chassis but also raises the center of gravity, which makes side-hilling worse. A shorter tire keeps the rig planted but can drag the skid plate on ledges.

For a VS4-10-based build with KM720 Roswell wheels, a 4.5 to 4.75-inch tall tire is a safe middle ground. Go taller only if you have already added weight down low and are willing to re-gear or accept slower acceleration. Go shorter if you run tight, technical lines where a low center of gravity matters more than clearance.

• Measure your current tire height before buying so you know your baseline.
• Taller tires need more steering clearance at full lock and compression.
• If you change tire height a lot, check that the body still clears the tires.

Compound and foam decide real-world grip

Tire compound is the single biggest grip variable after bead fit. Soft compounds conform to rock and roots but wear faster on abrasive surfaces. Medium compounds last longer and still work well on mixed terrain. Hard compounds are best for wet, muddy conditions where a soft tire would pack up or tear.

Foam choice matters just as much. Closed-cell foams hold their shape under load and resist water, which suits heavy scale rigs. Open-cell foams conform more but can break down over time. If you drive in wet conditions, pair a medium compound with a closed-cell foam and plan to dry the tires after each run.

• Soft compound for dry rock and competition lines.
• Medium compound for all-around trail driving and longer tire life.
• Closed-cell foam for heavy rigs and wet conditions.

Hardware and maintenance that make tire swaps easier

Beadlock wheels mean you will remove and reinstall a lot of small screws. Using the right driver tip protects both the screws and your patience. Vanquish Products offers a 1/4 inch Drive Nut Driver Tip in 5.5mm, 7mm, and 8mm sizes, so you can match the tip to the nut or screw you are turning instead of forcing a close-enough tool.

If you are also servicing shocks while the wheels are off, keep rebuild parts on hand. The Incision 90mm Scale Shock Rebuild Kit includes X-rings and bladders for one pair of shocks, which covers the common wear items that cause leaks and inconsistent damping. Doing both jobs in one session saves you from pulling the wheels twice.

• Keep spare beadlock rings if you frequently run rocky terrain.
• Replace shock X-rings and bladders before they start leaking.
• Batch tire and shock work so you only disassemble once.

Decision rules for matching tires to KM720 Roswell wheels

• Rule 1: Bead profile first: Confirm the tire bead sits flat on the wheel with the outer ring removed. If it does not seat, no amount of tuning will fix it. Fit is binary. A tire that will not seat is the wrong tire.
• Rule 2: Height follows terrain: Choose 4.5 to 4.75 inches for mixed trail use. Go taller only with added low weight and steering clearance. Go shorter for technical, low-CG builds. Match height to your lines, not to what looks aggressive in photos.
• Rule 3: Compound and foam work together: Soft compound plus open-cell foam for dry rock. Medium compound plus closed-cell foam for wet or heavy rigs. Pick the pair, not just the tire.
• Rule 4: Plan the hardware: Use the correct nut driver tip size and keep spare beadlock rings if you run rocky terrain often. The right tools turn a frustrating tire swap into a quick one.

Vanquish Products parts that support tire and wheel work

• 1.9 Spyder Beadlock: Vanquish Products 1.9 Aluminum Beadlock Ring can be used with Vanquish Products Method, KMC, and OMF Vanquish wheels that use a bolt-on outer beadlock ring. It is not compatible with Method Roost or Incision wheels. If you damage a ring on a KM720 wheel, this is a direct replacement option, but check your wheel model first because it will not fit every Vanquish wheel.
• 1/4" Drive Nut Driver Tip: Vanquish Products 1/4 inch Nut Driver Tip is offered in 5.5mm, 7mm, and 8mm sizes, with hardened chromoly and a black oxide coating. Beadlock wheels use small hardware that is easy to strip. Matching the tip to the fastener size makes tire changes faster and protects the screws.
• Incision 90mm Scale Shock Rebuild Kit: The Incision 90mm Scale Shock Rebuild Kit includes X-rings and bladders for one pair of shocks and is intended for rebuild use. If you are already pulling wheels to change tires, servicing shocks at the same time keeps the rig consistent and avoids a second teardown.

Who these wheels and tire choices suit

Best for

• Scale crawler builders using Incision KMC 1.9 KM720 Roswell wheels who want a repeatable tire selection process
• Drivers who swap between dry rock and wet trail conditions and need a compound and foam strategy
• VS4-10 owners who want to service shocks and tires in the same session

Not for

• Owners of Method Roost or Incision wheels looking for a beadlock ring replacement, because the 1.9 Spyder Beadlock does not fit those wheels
• Drivers who want a glue-on tire solution and never plan to change tires
• Builders who need a specific tire height outside the common 1.9 scale range without checking body and steering clearance first

Tire selection for the Incision KMC 1.9 KM720 Roswell wheel comes down to bead fit, height, compound, and foam, in that order. Get the bead to seat cleanly, choose a height that matches your terrain and build, then pair the compound with the right foam. Keep the correct nut driver tip and a few spare parts on hand, and tire changes become a normal part of your maintenance routine instead of a project.