Ignore the displacement number and read two columns instead: seat height and transmission. The X1 at 23 inches and fully automatic is a first bike. The X2 adds a semi-automatic four-speed at 28 inches. The X3 introduces a clutch lever at 32 inches. The X4 and X5 are five-speed manual adult bikes at 35 and 36 inches. Buy the tallest bike the rider can flat-foot and the simplest transmission they will not be bored by in a year.
- Seat height is the real sizing axis: 23, 28, 32, 35 and 36 inches across the five bikes.
- The transmission ladder — automatic, semi-automatic, clutch, five-speed — matters more than cc.
- Every X-series bike ships with an adjustable speed limiter, so top speed is a ceiling, not a setting.
- All five have electric start, and the X2 and up add kick start as a backup.
- MotoTec's sheet lists two max rider weights per bike — we quote the lower, more conservative figure.
The MotoTec X-series is the cleanest ladder in the catalog: five bikes, one design language, and a genuine step in capability at each rung. It is also the range people most often buy wrong, because the obvious way to choose — pick the cc that sounds right — is the least useful column on the page.
The full comparison
| Bike | Engine | Transmission | Seat height | Top speed | Max rider | Price today |
|---|---|---|---|---|---|---|
| X1 | 110cc (107 ml) | Automatic, single gear | 23 in | 37 mph | 125 lb | $899 |
| X2 | 110cc (107 ml) | Semi-auto N-1-2-3-4 | 28 in | 45 mph | 145 lb | $1,099 |
| X3 | 125cc (124 ml) | Manual, clutch lever | 32 in | 47 mph | 145 lb | $1,299 |
| X4 | 150cc (144.6 ml) | Manual 5-speed, wet clutch | 35 in | 56 mph | 175 lb | $1,599 |
| X5 | 250cc (223cc) | Manual 5-speed, wet clutch | 36 in | 62 mph | 175 lb | $1,999 |
MotoTec's own spec sheets list two different max rider weights for each X-series bike — for example 160 lb and 125 lb on the X1. We have quoted the lower figure in the table because that is the safe direction to round when the source disagrees with itself. If you are near either number, ask us and we will get it confirmed rather than guess.
Which one should you buy?
Buy the X1 if the rider has never ridden
$899, 23-inch seat, one gear, twist and go. A fully automatic transmission removes the entire clutch problem from a first season, and 23 inches means a smaller rider can get both feet down while learning. The adjustable limiter lets a parent hand over 15 mph now and 37 mph later. This is the bike that stops a first year being spent stalling.
Buy the X2 if they have ridden and want gears without a clutch
$1,099, 28-inch seat, semi-automatic N-1-2-3-4. Same 110cc engine as the X1, but the rider shifts through four gears with no clutch lever — the intermediate step that teaches shift timing before adding a hand to the equation. Top speed climbs to 45 mph and the bike gains kick start alongside the electric button. The five-inch jump in seat height is the constraint: measure the rider first.
Buy the X3 to learn the clutch
$1,299, 32-inch seat, 125cc, manual with a clutch lever. This is where the X-series becomes a proper motorcycle. 47 mph, a real gearbox, and a seat height that most adults and taller teens can manage. If the rider already handles an automatic confidently and is frustrated by it, this is the correct purchase — not the X2.
Buy the X4 or X5 if the rider is an adult
$1,599 and $1,999, 35 and 36-inch seats, five-speed wet multi-plate clutch. The X4's 150cc (144.6 ml) engine runs to 56 mph; the X5's 250cc (223cc Zongsheng) runs to 62 mph. Both take a 175 lb rider. At these heights and speeds you are buying a full-size trail bike, and the gear conversation stops being optional — read helmets and gear in the order that matters before the first ride.
How do you size a dirt bike to a rider?
Seat height against inseam, every time. A rider who can put the balls of both feet down at a stop is on the right bike; a rider on tiptoes is on too much bike and will drop it in the first parking lot. Then check transmission: a rider who has never used a clutch on anything should not learn it and learn a new bike simultaneously. Our engine size by age and height guide works through the whole MotoTec ladder, gas and electric.
What they all share
- Electric start on every model, with a 12V battery; kick start as a backup from the X2 up.
- An adjustable speed limiter on all five, which is the single most useful feature on a bike a young rider is growing into.
- Air-cooled four-stroke single cylinders running SAE 10w/40 — no premix, no two-stroke oil.
- A 60-day parts-replacement warranty, handled by MotoTec directly.
Parts support, by model
Each X-series bike has its own parts catalog on this store, so a plastic, a sprocket or a carburettor is looked up against your exact bike rather than a family: X1 110cc parts, X2 110cc parts, X3 125cc parts, X4 150cc parts and X5 250cc parts. Some components — the ignition coil, for one — are shared across all five, and the fitment tags say so.
