Allright guys,
I've got a few questions regarding a few things on my mc21.
I still have an original airbox lid, no holes or cuts.

How many holes does one drill out to 20mm(?) Where abouts on the lid?
I noticed that the mc28 model has an airbox cover with 2 small pipes
On the sides of the intake tubes, do the do anything for airflow?


I got given a spare woodruff key that alters the ignition timing by 2 degrees
but I'm unsure which side of the key actually alters the timing?

I've done the orange wire splice and was wondering if it'd be easier
to do this mod without faffing around with the modded woodruff key?
Would the gains be the same?
One thing is cutting 3 wires, another is removing the flywheel, cover, fairing ect.

Where does one enquire about changing main jets, slow jets etc?
Cheers!

Important note: I do not allow jetting discussion in the public forums, for historic reasons.

First of all, please thoroughly read through our ignition and carburation tuning pages on the Main Site: https://nsr-world.com/nsr250r-tuning/

Second, the MC21 doesn't need a modification to the flywheel setting [with an offset woodruff key]. The PGM-III, in delimited form, is capable of well in excess of 70hp.

Airbox lid modifications and alternatives are covered on the Carburation page in the Tuning section of the Main Site.

I'm not sure what you mean by "cutting 3 wires". The wire MC21 splice, again covered on the Ignition page in the Tuning section, shows the procedure. It's one wire to cut, and splice into another.

Please read through the pages detailed above, and if you are still having problems (or notice anything incorrect or unclear), let us know here.

May I also point you to the temporary page here, for various MC21 setups: https://manuals.nsr-world.com/view-pro-spec.php

Please note the page is not currently mobile friendly, and will need to be viewed on a tablet or laptop/desktop.
_________________
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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