In the underbone, or kapchai market, cost and value are of primary importance to most buyers. A margin of a few hundred ringgit can make the difference between the sales success, or failure, of such basic transport.

While some may look at kapchais as little more than bicycle replacements – which they are, in some markets – there is a category of riders who insist on pushing the envelope on such small displacement, underbone machines.

Although the author is loath to use the term “rempit“, there are times when taking a kapchai to the edge can be somewhat, entertaining. Manufacturers recognise this, especially in markets like Indonesia and Thailand, producing 150 cc underbone sports machines.

With the launch of the 2016 Honda RS150R, Boon Siew Honda has entered what is, for the company, a new market locally in 150 cc supercub category. This immediately brought it up against its closest rival in Malaysia, the Yamaha Y15ZR, and we couldn’t resist putting them side-by-side.


When Yamaha released the Y15ZR last year, it showed that it was serious about taking charge of the small-capacity bike market. With four kapchais alongside four scooters, Hong Leong Yamaha has a total of nine models in the under-150 cc category.

This was followed this year with the launch of the RS150R, Honda’s contribution to the supercub category. While this is not an out-and-out comparison test, this review will serve to highlight the main differences between each model, with each supercub standing on its own merits.

Physically, on the first approach, both machines are similar in size, with the Y15ZR standing a little shorter in the saddle, but not enough to make a real difference. The RS150R weighs in at 123 kg while the Y15ZR carries 115 kg.


In the engine room, the Y15ZR carries a 149.7 cc liquid-cooled single-cylinder that puts out 15.1 hp at 8,500 rpm, and 13.8 Nm of torque at 7,000 rpm. Numbers for the Honda RS150R are almost the same, with a 149.1 cc liquid-cooled single producing 15.3 hp at 9,000 rpm and 13.5 Nm of torque at 6,500 rpm.

As can be seen, on paper, the two bikes put out virtually the same performance numbers, but trust us when we say both supercubs have very different characters. This does not mean that one is better than the other, but either bike will appeal to riders with differing riding styles.

The biggest difference between the Y15ZR and the RS150R is the gearbox, where the Y15ZR gets a five-speed box, with the RS150R rider rowing six gears. This doesn’t really make a major difference performance wise, as the RS150R’s top gear functions more as an overdrive, as opposed to bringing the bike to a higher top-end speed.


In terms of physical riding position, both bikes are almost identical, with the RS150R having a slightly turned-in slant to the handlebars. The higher seat height of the RS150R places the rider in a more upright position.

Riding off on the Y15ZR, clutch engagement was precise and quick. A soft click of the lever into first, and the clutch was positive, allowing the Y15ZR to accelerate quickly. At second and third, there was a slight buzz in the handlebars.

We didn’t mind it so much, as a change to heavier aftermarket weights would likely solve the problem. Footpeg placement is about right, placing the feet in a neutral position.


Ground clearance was a little on the short side though, for the author’s size 10 boots. Launching into corners, the Y15ZR displayed good manners, and its quick acceleration, rowing through the five-speed gearbox, was a plus, with positive engagement.

This supercub certainly did draw a lot from Yamaha’s racing heritage, and it showed. Braking, with the front and rear discs, was good, a hard squeeze on the front brake giving good bite and feedback.

Comfort from the Y15ZR’s seat was good, with a slight hump at the back to keep the rider in place. A slight buzziness from the engine was felt through the seat. We cannot comment on how this would affect the rider on more long-distance journeys, but we assume stopping often would be a remedy.


While we didn’t actually perform any consumption testing on the Y15ZR, the 4.2-litre tank was good enough for about 120 km range, roughly. The free-revving engine certainly made keeping a light hand on the throttle difficult, with the light throttle pull encouraging the rider to wind it open.

Fuelling was almost faultless on the Y15ZR, with the EFI system showing only the slightest hint of a stumble at very small throttle openings, or when whacked open in top gear. The short gearing on the Y15ZR is meant for quick acceleration, and needed a couple of gears down for the bike to respond, so don’t treat the engine like it is a large V-twin.

In the cockpit, a large analogue speedometer sits on the left side, with an LCD display on the right. The usual information is displayed in the panel, including odometer, fuel gauge and so on.

Out front a pair of LED daytime running lights occupy the bottom half of the front cowl, and a single halogen beam sits in the handlebar fairing. The turn signals on the Y15ZR are integrated into the front cowl, giving the face of the bike a very clean look with no signals on stalks sticking out.

Moving over to the Honda RS150R, it gives the appearance of a much slimmer bike, although both the Yamaha Y15ZR and it are physically about the same size. The saddle, as mentioned earlier, is a touch taller, but not enough to make that much of a difference in terms of rider accommodation.

The handlebars on the RS150R are a bit wider than the Y15ZR, which, while giving a light touch to the steering, also led to over-controlling the bars at high speed. So, when riding off on the Honda for the first time, keep the steering movements to a minimum, until you get used to it.


Being heavier, at 8 kg more, acceleration on the RS150R was a tad leisurely. We found this to be the case with the test unit we rode in Teluk Intan during the media ride, and this review bike was about the same.

We wondered this would have been so, since the RS150R comes with a six-speed ‘box – proudly displayed during start-up in the LCD instrument panel – and if swapping out sprockets might give the bike slightly more sprightly acceleration. Regardless, The RS150R is geared for the top speed to be, well, sufficient.

Just keep an eye out for express buses coming up behind you and you’ll be fine. Highway comfort notwithstanding, we found the RS150R’s seat to be a tad on the firm side, enough for us to start shifting uncomfortably in the seat after a half-hour or so.


Aftermarket add-ons might step up to the plate here, or perhaps the seat simply needs bedding in over time. This is a continuous hazard faced by reviewers, as we rarely get vehicles long enough for its true idiosyncrasies to come to the fore.

Handling on the RS150R was good, enough that we didn’t worry about chucking the bike into corners at stupid speeds. There was adequate feedback from the tyres and suspension, with perhaps the rear shock needing a touch less pre-load.

Highway riding on the RS150R was interesting, with something like 130 km/h showing on the clock. No, we don’t usually post top speed figures for the bikes we test, but in this case, with speedometer error, we reckon the speed would have been about 125 km/h or so.


The wide bars helped in this regard, allowing for quick changes in direction, but, this is true of almost any machine in the kapchai-class. That we didn’t notice the steering on the RS150R is testament that the bike’s balance is pretty good.

For rider accommodation, the instruments with an analogue tachometer and digital speedometer were clear and legible. It did amuse the author to see the words “6-speed” come on the LCD screen during start-up, a reference to the RS150R’s six-speed box.

Headlights on the RS150R are double-stacked, with separate beams for the main- and high-beams. We did take the RS150R out at night a few times, and while the beam throw was adequate, it would be prudent to dial the speed down a bit in darkness.


Range from the 4.5-litre tank was acceptable, clocking in at about 120 km or so. Again, we didn’t put much attention to fuel consumption, since, as a city bike, a rider would not be far from a petrol station anyway.

Coming down to the brass tacks, what everyone wants to know about is price. The 2016 Yamaha Y15ZR retails for RM8,210, including GST. There are three colour options – grey, blue and red (as tested).

For the 2016 Honda RS150R, the listed price is RM8,213, including GST, for the standard model, and RM8,372, including GST, for the advanced. The standard comes in Matte Blue (as tested) or Matte Black, while the advanced comes in Metallic Red and Repsol Racing.


So, is this a comparison of the 2016 Yamaha Y15ZR and the 2016 Honda RS150R? Yes, and no. While the two bikes occupy the very same market niche, and boast very similar specs, we found, during testing, that the duo will appeal to very different riders.

If you’re the kind of rider who likes cut-and-thrust riding, and dicing with traffic, along with quick acceleration, then the Yamaha YZ15ZR fits that mould. The Honda RS150R, on the other hand, would be more like a touring bike, building up the speed slowly, but staying there comfortably till the fuel runs out.


And which would we choose? Again, it’s a tough call. More often than not, it boils down to looks and personal/brand preference. In terms of top speed, both supercubs are within a hair of each other. The Yamaha gets the vote for handling, while the Honda wins for straight-line stability.

At the end of it, for the author, the 2016 Yamaha Y15ZR gets the pick for city riding, winning on the basis of cost, handling and general rider accommodation. The 2016 Honda RS150R, on the other hand, would be rolled out for slightly longer journeys, where the bike’s stability wins out.