The Yamaha R3 has garnered a fair bit of attention from the media and enthusiasts over the country since its launch for multiple reasons. With the riding impressions already out, it was time to find out more on the technology details of the motorcycle. The company invited us to a technical briefing on the R3, carried out by a team of Indian and Japanese engineers. We bring you the important technical highlights.
KNOWING THE INTERNALS
The R3 is powered by a 321 cc liquid-cooled, in-line twin-cylinder engine. Breathing through a DOHC 4-valve system, the engine develops about 41 hp and 29.6 Nm of torque. This unit uses Yamaha's famed DiASil cylinder, which was the world's first all-aluminium die-cast cylinder at the time of its launch around 2002. In the R3, the DiASil cylinder helps reduce engine weight. The cylinder, which itself is significantly thinner than the conventional one, improves cooling performance, thereby reducing power loss.
DiASil cylinder is manufactured using Yamaha's Controlled Filling (CF) Die Casting technology. This process enables mass-production of aluminium die-cast parts that are both large and thin in sections, enabling the production of lighter products with fewer parts. Focussing on improving the flow characteristics of the molten aluminium as it is poured into the metallic mould, this process is claimed to improve the smoothness of the flow into the mould by increasing the vacuum inside the die, regulating the temperature of the die and improving the injection speed of the molten aluminium. As a result, CF die-cast aluminium parts have an air-intrusion rate of about one-fifth of conventional die casting, reducing air bubble formation. This technology is unique on the material front as well, using 20 % silicon with aluminium. Inside these cylinders are forged aluminium pistons squeezing the air-fuel mixture to a high 11.2:1 ratio.
We reported earlier on the smooth operation of the R3's engine and a couple of things contribute significantly to this nature. One of them is the cylinder being offset by seven mm, which reduces the friction and is similar to the flagship R1. Unlike the R1 though, which has a crossplane crank, the R3 uses a 180º crankshaft, which is more of a conventional technology but effective for the amount of power the R3 engine develops. In simpler words, a 180º crankshaft means that among the vertically-placed cylinders, when one piston is at its peak lift, the other one is at the bottom.
While we've discussed technologies that the R3 benefits by borrowing form its larger-capacity siblings, things turn conventional here onwards. The frame on the R3 unlike the R1 and even the smaller R15 isn't Deltabox type but a diamond-type. Made of steel, this frame design was selected in interest of weight-saving, Yamaha officials told us. The frame with 35 mm diameter tubes seems to have fulfilled this claim by weighing only 16.79 kg. The swingarm is made of steel as well, and its length ratio is similar to that of the R1.
The suspension kit again is conventional with non-adjustable 41 mm KYB telescopic forks upfront and a preload-adjustable single shock at the rear. Suspension travel though is generous at 130 mm for the front and 125 mm for the rear, adding to the comfort. A 298 mm single-disc at the front and a 220 mm unit at the rear do the hauling duty. Unfortunately, they aren't supported by ABS in case of a rider failing to avoid a wheel lock-up. In case, you're still searching for similarities with the R1, the R3's discs are 4.5 mm thick, while the R1's are 5 mm; pretty close!
The technical session helped us understand the R3's configuration better. The selection of the frame design and suspension set-up wasn't convincing earlier. Targeting a daily-rider and the cost-consciousness of the average buyer in developing markets though offers some convincing.
Yamaha seem to have actually done a good job at using modern technology from its premium models and balanced them with some conventional yet effective technologies. On those grounds, the R3 is a convincing technology package and easily the best-looking one in its segment. What didn't convince us though, despite an explanation from the officials, was the omission of ABS, even as an option. As and when required, the company can offer the technology and with the new ruling from the Indian government mandating it, ABS-equipped R3 shouldn't be far off.
Text: Arpit Mahendra