With the greatest of resoect, Ian, your post is exactly why I do not allow jetting discussion on the public forums.

There are many variables, including, but certainly not limited to, air density, air temperature & humidty, fuel type, ignition, and compression. Spark plug type, even manufacturer, can affect jetting, as can different air cleaners. That's before you even consider the expansion chamber type and make... yes, changing from a set of Jha chambers to a set of TYGAs can even necessitate a change of jetting, let alone changing from a stock set. Just changing the silencers to a set of Swarbricks or similar can make a difference.

TYGA will probably give you a baseline setting, but every bike is different. You cannot even take two MC28s with the same specification and guarantee that they need the same jetting. Yes, all stock NSRs (like-for-like) use the same settings, but factory settings, both jetting and ignition, are very safe. (Standard motors are effectively detuned by approx. 30%.)

TL:DR

Many years ago, on the previous incarnation of this forum, someone posted their MC21 settings for someone else. Their motor subsequently seized, and they tried to hold me responsible "for allowing/hosting the information". Yes, those kind of people exist, and for that reason I do not allow jetting discussion here.
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Andy.
NSR-WORLD.COM

Please keep all responses to Forum posts on the Forum so that others may benefit.

Please DO NOT PM me for technical advice. My time is precious, and you will probably receive a faster response on the Forum anyway.

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