Yamaha's YZ125 must surely be regarded as one of its most successful models ever.
It's won five AMA National Motocross Championships in the USA and dozens of state and regional titles all over the world. It debuted in 1974 at a time when two-strokes were still well and truly the dominant force in motocross. The fact that it was a 125cc machine didn't alter anything and it quickly established itself as one of the front runners in a very competitive world.
The concept reached its peak with the models built between the mid-90s and 2000 and many an ex-racer will get misty-eyed about these models. Early bikes (up to 1980) had an air-cooled engine while later models used liquid cooling to boost power and durability.
Yamaha YZ125 On The Road
The YZ125 is still being made, meaning that there's now roughly 35 models to choose from (Yamaha has updated the bike every year). With that in mind, an early air-cooled bike will be a very different animal to a later liquid-cooled version which will have much better brakes and suspension and will be a fair bit faster. But even the original YZ125 should, if it's in decent condition, still have plenty of sizzle and while it won't be competitive in a race, it will still scare the pants off anybody who gets lairy with it. Those 1996-2000 models we were talking about just seemed to hit a sweet spot in terms of their balance and the way the engine made its power. The broad power-band was the real key to it, not something that other small-capacity dirt bikes manage to pull off.
What to look for when buying a used Yamaha YZ125
An old bike is likely to have spent at least a few years in a shed, hiding behind piles of firewood and old tyres, gradually gathering spiders. The best you can hope for is that somebody threw an old sheet over it before switching off the light. In the case of such a bike, it'll virtually need a complete rebuild to get it back to proper working order.
Newer bikes are less likely to have been shelved for long periods, but you still need to watch for crash damage, trashed suspension and worn out chains, sprockets and tyres. Check the steering head bearings for play because a lot of YZ125s have had big air under them at some stage.
Yamaha YZ125 Standard Specifications
Years: 1974 - current
Engine size: 125cc
Fuel system: carburettor
Standard transmission: 5/-speed
Yamaha YZ125 Final Verdict
+ Seminal crosser. Big street cred
+ Reliable and tough
+ Mid-90s models were real sweeties
- What's its history?
- Crash damage