It is hard not to look back at your youth with a rose-tinted visor and lament the loss of the bike that started you on your two-wheeled path. We all sympathise with future generations who are being forced to deal with what, in our view, are pale imitations of our glorious youthful steeds. For many of us it all started with a two-stroke 125cc that screamed us up to dizzying speeds, but we gloss over the fact we were changing pistons every few weeks and our clothes stank of two-stroke smoke.
I’m going to hold my hand up and say that while I love nostalgia, you have to look at the current crop of four-stroke sports 125s and admit they are pretty special. And for 2019 Yamaha have pulled out all the stops to make their new YZF-R125 really stand out from the crowd.
Now in its third generation, Yamaha has gone to town with this revised model. Starting at the basics, it gets a new steel Deltabox frame with a beefier aluminium swingarm and altered geometry. Add to this 41mm inverted KYB forks (that are gripped by a MotoGP-style top yoke) and a single radial four-piston brake caliper (with ABS) as well as a wider 140-section rear tyre and you can see handling was one of its key design criteria. As if this wasn’t enough, the bike has also received a total facelift with an R1-inspired fairing, LED lights and even a MotoGP-style brake lever protector as standard equipment. How cool is that! And it doesn’t stop there, while this may not impress a teenage tear-away as much as the YZR-M1-style air scoop or new LCD display, the motor also contains some pretty trick tech.
Within the SOHC four-valve single cylinder four-stroke motor, Yamaha have incorporated variable valve timing technology. Called VVA (Variable Valve Actuation) it is a simple but effective solution to give the 125 a bit more torque without breaking the A1-licence imposed power cap. Without getting too complicated, the intake rocker (the bit that pushes the valves open) comprises of two parts that both follow the camshaft’s lobe but have different profiles. At low revs only one part opens the valves, but at 7400rpm a servo is activated that locks the two together parts, allowing the one with a more aggressive profile to take over and alter the motor’s valve timing. Yamaha claim these dual lift heights give the motor more torque low down than the old engine while also boosting top end performance. Alongside larger valves, new throttle bodies and a bigger volume airbox, they say VVA has seen the R125’s torque increase throughout its midrange despite its peak valves being pretty much unaltered. But can you really spot the performance gain on a 125 with just shy of 15bhp and 9.2lb.ft of torque? Surprisingly, you can.
On the road the R125 not only sounds far fruitier than the outgoing model, it definitely has a bit more grunt in its low rev range. This may be in part due to Yamaha altering its final drive sprocket from a 48 to a 52-tooth item, but I’m confident the VVA is also contributing as the motor feels stronger and less inclined to bog down and require a rapid downshift of gears to regain drive. While less apparent on the open road where the little motor is generally pinned well above the 7400rpm point the VVA is activated, it is in town when you are zipping through traffic that the system feels like it is genuinely making a positive difference. I wouldn’t say it is a radical game-changer, but it is certainly worth having and doesn’t detract at all from the engine’s natural ease of use. Does it make a difference at the top end of the revs? Yamaha claim the R125 now has a higher top speed and I saw an indicated 88mph on a motorway, so the signs are certainly promising! But engine performance is only part of the story of the new YZF-R125 as its handling has also been enhanced.
As well as being race rep in looks, the YZF-R125 is also a proper little sportsbike in the way it handles. Armed with decent Michelin Pilot Street tyres and a chassis that is built for sporty riding you can really enjoy the R125 in the bends. Thanks to the width of the tyres there are bags of grip and the KYB suspension is also impressive in its performance while the radial front brake has lots of bite, if not much in the way of feel. We tested the R125 on a track and it was fun, although I can’t see many finding their way onto race circuits. What matters to a teenager (and Yamaha reckon 40% of the R125’s buyers are aged between 16 and 17 years old) is that it looks like it can kick some track backside and on that score the new look certainly wins. And if you need to put your sensible hat on, and this is always a very small consideration in any teenager’s mind, Yamaha claim the R125 will do 132mpg, it still has a fantastic ‘big-bike’ feel to suit even the lankiest of teenagers and it costs £4499, which is the same amount as the outgoing model cost last year despite its substantial updates for 2019. Everyone’s a winner!
Engine: 124.7cc liquid-cooled 4v SOHC single
Power: 14.8bhp @ 9000rpm
Torque: 9.2lb.ft @8000rpm
Claimed economy: 132mpg