Hello, I have a Yamaha XJ600S Diversion. 4 cylinder engine which is very smooth or should be. It is the version of 1997 with throttling to 48hp by suction nozzle. I changed oil and spark plugs myself and then I was with the machine in the workshop –> was made the following: 1.) Valve play set (was my wish because the manufacturer recommended this at 36.000km according to maintenance plan and the machine already has about 35,000km on it, last maintenance was at 6000km) 2.) Valve end (the old one would have been brittle says the workshop) 3.) Carburettor set (according to the workshop necessary because the engine would have run on only 3 cylinders before) 4.) Intake nozzles replaced 5.) Air filter changed I paid for everything together 300€ including material and taxes. What annoyed me is that the workshop did not point out that there are also unrestricted intake nozzles and that the throttling takes place at all through the intake nozzle. So wu I would have expected from an expert (workshop) that he would explain it to the layman (customer = me) and not just leave it in the rain. So the workshop is something “maulfaul”. But my big problem is: Since I was in the workshop the machine vibrates very strongly, at about 4000 revolutions it starts strongly and at 6,000 revolutions it is particularly crazily. The rearview mirrors now show everything distorted from approx. 100 kmh because of the vibrations and my hand is almost deaf after an hour. Yesterday I drove 2 hours and this morning my hand is still deaf!! That’s not normal? I have the feeling that my fingers are dying off if I drive with it even longer… Something is really lazy. Does it have to do with what the workshop has done up there? Should I post what values have set during the valve game? I still have the note. It seems “Spanish” to me. Thank you! Greetings,