RD350 R  1986-1995 RD350 R

Well, Yamaha stopped making them in 1991, so you would have thought "that was the end of production".

But, no - a Yamaha subsidiary in Brazil, called Yamaha Motor da Amazonia, had been making the RD350 R model quietly in the background for years, since 1986. This was partly to get round restrictions for importing Japanese-made products into some countries. They continued making them in Brazil when Yamaha stopped production in Japan and soon Mitsui started importing them into the UK. Because they first arrived in the UK some time after Yamaha stopped production, it is often assumed that Yamaha sold the F2 jigs and moulds to a separate company for the sole purpose of continuing production of the RD350, but that was not the case.

The R model was deliberately strangled in power by an exhaust restriction, and by a low compression head. But this can be undone. They are 'bitsa' bikes and use the barrels and carbs of the earliest YPVS model, the LC2. However, the electrics and ignition still stop it revving freely.

The R is often run-down as badly built. This is probably because the Brazilian-made petrol tank and frame do rust much quicker than the Yamaha ones. However, in all other respects, the quality and reliability are just as good - or bad - as Yamaha. The truth is that both the authentic Yamaha bikes and the Brazilian-made ones where generally manufactured inaccurately, and consequently deliver a good deal less power than Yamaha claim. They require rebuilding to tolerance in order to achieve the claimed power. This process is called 'blueprinting'. They particularly benefit from attention to the squish-band gap, the exhaust path, the reed cages, port radiusing and de-burring.

The UK engine-number prefix is 4CE but they are universally called an 'R'.