DBDirt Bike Finder
MotocrossEnduroOff-roadTrailMiniDual-sport

Marketplace coming soon

Dirt Bike Finder

US dirt bike specs and used listings — browse bikes and run the garage calculators while the full marketplace rolls out.

Browse bikes

Hot listings

See All

Shop by class

Motocross

33 listed

Enduro

22 listed

Off-road

5 listed

Trail

15 listed

Mini

20 listed

Dual-sport

7 listed

Shop by brand

See All
YamahaHondaKawasakiSuzukiKTMHusqvarnaGasGasBetaShercoTriumphStarkFanticCobraSSR Motorsports

Have a bike to move?

Turn your dirt bike into cash.

List in a few steps. Buyers can compare similar models by brand and class, then punch the specs into sag, sprocket, and power-to-weight tools.

Check similar listingsGarage calculators

Why Dirt Bike Finder?

Shop new and used.

Discover a mix of private-party and dealer bikes, priced for any budget and class.

A community built for you.

Built for riders — motocross, enduro, trail, and dual-sport, not generic classifieds.

Turn your items into cash.

Have a bike you no longer need? Compare comps, then list it in a few steps.

Check the bike before you buy.

Hours, condition, and garage calculators so the classified matches the bike in the dirt.

Dirt bikes for sale

See All

From the pits

“I needed a woods 300 and found three comps in one place, then ran the sag numbers before I drove out. Saved me a bad buy.”

Seth Underwood

“As someone always rotating bikes, being able to browse by class and check gearing in a couple clicks is how this should work.”

Luc Santos

“The listings are dialed and the calculators are sitting right there. Best way to shop used MX without guessing.”

Darian Sanayei

“Snap a few details, compare similar bikes, and you know if the ask is real. That’s the classifieds motocross needed.”

Fernando Ramos

Calculators for the bike you just found

After you pick a listing, check power-to-weight, sprockets, sag, and premix so the classified matches the bike in the dirt.

01 / Performance

Performance

Horsepower, torque, gearing, and how fast the bike actually goes.

10
Horsepower
Convert crank torque and RPM into horsepower and kilowatts. Use a dyno torque reading or a manufacturer peak-torque figure.

Open calculator →

Torque
Back-solve torque from horsepower and RPM. Useful when a spec sheet lists peak HP but not the matching torque figure.

Open calculator →

Power-to-Weight
Compare bikes the way they actually feel: horsepower against wet bike weight plus rider. Higher hp/lb (and W/kg) means a snappier chassis.

Open calculator →

Top Speed
Estimate gearing-limited top speed in high gear at a given RPM. This is the speed the sprockets and tire will allow — not a drag-strip prediction.

Open calculator →

0–60 Acceleration
A power-limited estimate of 0–60 mph time from horsepower, ready-to-ride weight, and drivetrain loss. Ignores wheelie, traction, and aero.

Open calculator →

Gear Ratio
Turn gearbox tooth counts (or published ratios) into overall ratio per gear, including primary and sprockets.

Open calculator →

Final Drive Ratio
Final drive is rear sprocket teeth divided by countershaft (front) sprocket teeth. This is the ratio you change with a sprocket swap.

Open calculator →

RPM
Find engine RPM at a given road speed from overall gearing and rear tire diameter.

Open calculator →

Speed vs RPM
Build a speed table for one gear across the rev range. Use it to see where a shift lands or how a sprocket change moves road speed.

Open calculator →

Wheel RPM
Rear-wheel revolutions per minute from road speed and tire diameter. Independent of engine gearing.

Open calculator →

03 / Engine & Maintenance

Engine & Maintenance

Displacement, premix, valves, oil, and hour-based service intervals.

12
Engine Displacement
Swept volume from bore, stroke, and cylinder count. Output in cc, liters, and cubic inches.

Open calculator →

2-Stroke / 4-Stroke Displacement
Same swept volume math, plus a power-stroke comparison: a two-stroke fires every crank revolution, a four-stroke every other rev.

Open calculator →

Bore & Stroke
Solve the missing dimension. Leave bore at 0 to find bore from displacement and stroke, or stroke at 0 to find stroke from bore.

Open calculator →

Compression Ratio
Static CR from bore, stroke, head chamber, piston dome/dish, deck height, and head-gasket volume.

Open calculator →

Piston Displacement
Swept volume of one piston, plus mean piston speed at a chosen RPM. High mean piston speed is a durability red flag.

Open calculator →

Engine RPM
Engine speed from wheel speed when you already know final drive and the gear you are in. Tire diameter in inches.

Open calculator →

2-Stroke Premix Ratio
How much oil to pour for a given fuel volume and mix ratio. Works in gallons or liters, with common MX ratios on tap.

Open calculator →

Fuel-to-Oil Mix
Work backwards from oil already in the jug, or scale a mix to a larger can. Same math as premix, aimed at mixing benches.

Open calculator →

Valve Clearance
Shim-under-bucket math: new shim = old shim + (measured − spec). Too tight needs a thinner shim; too loose needs a thicker one.

Open calculator →

Oil Capacity
Look up a typical wet-sump fill for popular MX and enduro bikes, or enter a custom capacity. Includes a top-off from the dipstick/sight window.

Open calculator →

Spark Plug Gap
Convert plug gap between millimeters and inches, and compare against typical 2-stroke and 4-stroke dirt bike ranges.

Open calculator →

Engine Hours Maintenance
A practical MX / enduro service calendar from current hours and engine type. Intervals are conservative race-use numbers, not dealer marketing.

Open calculator →

04 / Suspension & Setup

Suspension & Setup

Sag, spring rate, travel, and ride height for race or trail.

10
Sag
Sag is how far the bike settles from fully extended. Measure from a fender mark to the axle with the bike on a stand, then on the ground.

Open calculator →

Race Sag
Race sag (rider sag) is measured with the rider in full gear, balanced on the pegs. Most MX bikes want about 100–108 mm on ~310 mm travel.

Open calculator →

Rider Sag
Front and rear rider sag together. Enter fender-to-axle (or a zip-tie on the fork stanchion) for each end.

Open calculator →

Static Sag
Static sag is bike-only, no rider. Too little static sag with correct race sag means the spring is too soft (you used a lot of preload). Too much static sag means the spring is too stiff.

Open calculator →

Spring Rate
Estimate fork and shock spring rates from rider weight, sag targets, and linkage leverage. A starting point for ordering springs — not a replacement for a tuner.

Open calculator →

Fork Spring Rate
Two fork springs share the front load. Convert between N/mm and lb/in, or size springs from rider weight and target sag.

Open calculator →

Shock Spring Rate
Size a rear shock spring from rider weight, target sag, and linkage leverage. Convert N/mm ↔ lb/in.

Open calculator →

Suspension Travel
How much wheel travel is left after sag, and how a zip-tie on the fork relates to percent used.

Open calculator →

Ride Height
Front vs rear ride height from fender-to-ground or axle-to-fender measurements. Use it after sag so the bike is not kicking or pushing.

Open calculator →

Suspension Setup
One worksheet: race sag, static sag, suggested spring direction, and a starting clicker map from rider weight.

Open calculator →

59 calculators indexed