83 heritage special valve adjustment? .002 and .006?

section8joe

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I'm adjusting my valves for the first time and I just want to make sure I use the correct feeler gauges. My haynes doen't have the xs650sk listed. It just has xs650A, B and C. Should I be using .002 and .006?
Thanks!!
 
According to this earlier thread, more clearance is better:
https://www.xs650.com/threads/us-custom-650-1981-bike-tappet-settings.46648/

Well, it does seem that Howard Smed and Yamaha disagree on the performance aspect, as Yamaha states improved performance with less clearance, while Smed says the opposite. Somehow I trust Smed on this one....I'll try his recommendations when spring arrives. Right now it is around minus 20C outside my front door......
 
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I read all that stuff about the larger clearances supposedly giving better performance and making more power, so after I rebuilt my '78 and installed the quieter running elephant foot adjuster screws, I decided to try them. I didn't notice any performance or power boost, the valves just made more noise, lol. Yes, even with those quieter running adjuster screws, get too big on the clearances and they clatter too. They do run quiet with slightly larger clearances though. For instance, my '78 originally specced .004" for the intakes but when I tried it, they ticked like crazy. Closing them up just .001", to .003", quieted them right down. But now with the elephant foot screws, I can quietly run .004" and I do.
 
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