The Yamaha YZF-R1, what is it? Basically I would call it big power in a small bike. The first Yamaha YZF-R1 in 1998 was explosive, savage and utterly uncompromising. By 2004 it was ripe for an overhaul: underseat exhaust system, angular bodywork and a claimed 180 horsepower at the rear wheel. In reality, it was within sniffing distance of 150 horses pushing the Yamaha R1, but who is counting.
The Yamaha YZF-R1 is build around an 998cc displacement engine. Over the last 10 years the engine of the Yamaha YZF-R1 did see some changes, the early models where 20 valve, DOHC, liquid-cooled Parallel 4-cylinder engine. It produces a compression ratio of 11.8:1, with a 74mm bore and 58mm Stroke. Equipped with 4 Mikuni CV downdraft BDSR40 carburetors. This specifications changed for the 2006 model of the Yamaha YZF-R1, the cylinder compression ratio went up to 12.4:1and respectively the Bore x Stroke changed to 77mm x 53.6mm. Also the fuel system changed of the Yamaha R1 it was now equipped with Fuel injection, dual-valve throttle bodies with motor-driven secondary valves Fuel Injection with YCC-T and YCC-I Compression Ratio. Some of this specs changed again in the 2007/2008 models. If you are considering buying a secondhand Yamaha YZF-R1 you should realize that it is basically a bike with a hooligan nature, by 2004 it has been given a slightly more practical, but not less exciting, edge, bringing better road manners by suspension improvements. In other words, it's a sports missile you can live with.
For the bigger boys, the Yamaha YZF-R1 has more legroom than rival 1000s and it makes a big difference to distance comfort.
The headstock and wheel bearings can have a hard life if it does a lot of hard-riding and trackdays. Check for a notchy headstock by pivoting the YZF-R1 on its sidestand and turning the bars. To check check the wheel, get a friend (maybe you want to take 2) to lift the bike and see if the wheels have any horizontal play.Some warning, the Yamaha YZF-R1 was once one of the most nicked motorcycles in the world, so be careful with the paperwork. Don't buy this bike if you believe something is not right.