I'm afraid the SP chassis were plucked randomly out of the production line. There's no specific prefix/suffix to identify them. For all intent and purposes, an SP is "just" an SE with Magteks... an SE is just an R with a dry clutch and adjustable suspension. In reality, it's going to be impossible to tell a genuine SP from a non-SP, unless you can get Honda to confirm it. (Varying success rate on having Honda confirm chassis numbers here in the UK.)
Basically, you will just have to play it by ear. Get a feel for the seller, and if anything causes you doubt, just trust your instincts. NSRs aren't cheap these days, and we've seen a lot sell for very good money that have required a lot of time and money spent after purchase! It can be a real minefield. There are some great bikes out there though, but the owners don't seem to want to sell them!
Finally, what do you want from the bike? If you want to derestrict it and hoon about like a looney, then an MC21 is the sensible choice. 60hp+ is yours pretty much for free, within an hour or so, and they are cheaper than an MC28. If you're looking for ultimate appreciation, then it's probably going to cost you in the form of an MC28. However, HRC jet kits are virtually nigh on impossible to get for them now, and derestricting them is expensive. Of course, the MC21s (and MC18s) are appreciating in value too.
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Andy.
NSR-WORLD.COM
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