These machines are very reliable, though not as fast as the RD350, but with the single carb, its pickup and speed is justifiable. Most of the parts, say almost 50-60% fit from Roadking. I own two of these beautiful yezdi 350 bikes, one is restored, the other one in the process. Since it comes with 18" rims, sadly, the front conical brake drum is missing. The previous owner has fitted comstar wheels(locally made and very heavy), so I had no alternative, except to replace it to 16". Now I have plans to use RK hubs in 18" with spokes.
In addition to these two babes, I also own 5 Roadkings. 1993, 1994, 1995(3 Nos.) They are very reliable and trustworthy, I have travelled a lot on them. Simplicity of mechanism, 30% moving parts(in the engine) as compared to OHC(IC) engines, with valves, timing chains, timing gears, cams and so many parts. According to me, the more moving parts, the more problematic. Best part of these Roadkings are that the wheels are interchangeable, which I think no indian bike has this plus point(save scooters)
Parts are still cheaper compare to the plastic bikes of these days., loads of second hand parts, engines are available in abundunt.
Overall a very reliable, trouble free motorcycle. It is very sad, that these machines had to depart from Indian scenario in late nineties.