msdavidson

That's useful. Thanks for the info. msdavidson

Hi I've just joined. I've got a 1992 Diversion that I built up from a box of bits 5 years ago. I use it as a winter bike and it has now done 59000 miles. It has always had a clunky gearbox - the worst I've ever experienced - and the timing chain tensioner has no adjustment left so I've decided to change the engine for a lower mileage one. The engine in the bike has a number that starts with 4BR which is the Yamaha model number. The new engine I've got starts 4DU and seems identical in every way. What is Yamaha model 4DU and what are the differences between the two engines. Can any one help please? msdavidson