Hmmm, Steve's "test models" for this comment are a wire spliced (so in fact not restricted at all) but otherwise standard MC18 and an MC28 running race pipes known to cut around 6-8bhp from the mid range and no air box lid (also dyno proven to cut around 2bhp from the same area).

In fact an '18 with the same pipes (red trace here) is 2bhp down on a '28 at 8000 rpm, as is a restricted '18.

So if anyone is running a '28 on std but derestricted pipes, an HRC card, modded airbox lid and has optimised the jetting for it they're welcome to post graphs.

But back to the 'card, a '28 will never make decent power on the std card, Tom picked up 12bhp on his 300 by just swapping cards and main jets.

You can run the HRC card if you do the wire splice (bottom of page) but you lose the speedo, oil light and neutral light.
With the HRC loom you also lose all road equipment and a ton of other bits (the fuse box for instance).
Power wise with the HRC card there is no difference between a wirespliced std loom and the HRC one, the splice just removes all the signals the HRC card doesn't understand or like. The HRC loom is just a ton tidier and a bit lighter (and three points in posers).
You can't "bypass" the card, it holds too much info, the '28 isn't restricted in the manner the '21 or '18 is, there is no artifical cutting of the power at higher revs or in higher gears. The ignition curve and powervalve settings are so mild it only makes 40bhp, there was no need to further limit its top speed!
Even advancing the timing (by fitting a '21 flywheel) doesn't restore any kind of powerband.

Fact is well set up a derestricted NSR will make around 61-63bhp, any more than that will require some work inside the engine.
Derestricting an MC18 or 21 is a bit of work the some wire cutters and a soldering iron, (actually an early MC18 has a bullet connector you can just pull apart), a modded airbox lid and some jets.
Derestricting an MC28 requires a £120 smart card, a bit of work the some wire cutters and a soldering iron and either some race pipes or quite a bit of action with the dremel (so I have been told, mine have been done), a modded airbox lid and some jets.

As the '21 and '28 are exactly the same geometry normal thought is the '28 is not worth bothering with unless you want a ss swingarm and the smartcard or think being able to take your rear wheel off in 15 seconds or put your racebike (which of course has no side stand) up on a paddock stand on your own is a waste of time.
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