The sport underbone class — Honda’s Winner R and Yamaha’s Exciter 155 — is where Vietnam’s manual-clutch riding lives. The gearbox is the heart of the experience, and the two bikes take slightly different approaches. Verified manufacturer data below (retrieved 23 September 2026).
What the class rides like
These are not commuter underbones with stickers: liquid-cooled engines (Winner R 149.2 cc, 11.5 kW; Exciter 155 cc, 13.2 kW with VVA), real clutches, sportier seat height (795 mm both, per the manufacturer pages), wider rear tyres (120/70-17) and disc brakes. The riding position leans you forward; the clutch is light but demands technique; the gears are close-ratio and usable.
The gearboxes
Yamaha publishes a six-speed gearbox with an Assist and Slipper clutch for the Exciter 155 VVA — the slipper function softens hard downshifts, and the assist function lightens the lever pull (our assist-and-slipper guide explains the mechanism). Honda’s Winner R page lists a manual clutch without publishing the gear count; on the bike, riders should simply use the full pattern as marked. Technique-wise both reward the same habits: shift up early in traffic, downshift one gear at a time with rev matching, and never coast with the clutch pulled.
Riding them in the city
The gearing is taller than a commuter’s first gear, so launches need slightly more revs than a Wave — the launch guide covers the release technique. In stop-and-go, the six-speed’s advantage is that second gear covers a wide band: many Exciter riders treat the bike as a three-speed in town (first to move, second for flow, third to cruise) and only open the full gearbox on open roads.
On open roads
This is where the class makes sense: confident overtaking, stable cruising and honest braking. The Exciter’s VVA engine keeps pulling high into the rev range, and the Winner R cruises comfortably at highway speeds. Our 150cc manual buyers guide ranks the whole class on verified data, and the Exciter and Winner R reviews have the full specifications.