Well, for starters it's not 5 bhp, it's about 20bhp.

Give me an mc21 and about an hour and I'll give you a 60bhp bike that'll make you giggle like a schoolgirl.

Give me an mc28, an unobtainable HRC card, a set of pipes, an (again unobtainable) HRC jet kit and about 4 hours and I'll give you 60 bhp much the same.
The only way to get an HRC card now is to source one with a PGMIV from Japan or trust someone who says (in Japanese) he can reprogram them. Both ways will see you parting with several hundred pounds.

There are ways to extract some extra power from an mc28, namely by fitting mc21 parts, presuming I can be bothered to drag the thing to Steve's we'll able to tell you soon enough what an mc21 engine attached to a PGMIV and some derestricted pipes makes (that's what my Rothmans '28 is), I'm guessing around 53bhp. It's a little bit flat compared to a full monty '18, '21 or HRC carded '28 but retains all the road kit and with some enthusiastic throttle use it can keep most 250s/400s in sight.

A 40bhp mc28 is absolute garbage and a 45 bhp mc21 isn't much better, in the UK if you're a full size guy the chances of being whipped by some 50kg kid on a hot 125 Cagiva Mito are pretty high.
But it's not the level of power thats so bad, if it was delivered in the manner of a full power 125 Cagiva or Aprilia that'd be fine, they're both a right laugh to ride.
But its not, they rev OKish round to about 8000 or so, much like a full power bike does, nothing exciting but it works, then they just throw in the towel and limp the rest of the way round in much the same manner.
Everything that's good about a two stroke is totally missing.
I'd never advise anyone to run any Jap restricted 250, they're all rubbish.

So it's £6500, plus maybe a grand to get the power out of it that you will be wanting within about a fortnight, that's £7500 (and any chance of a guarantee ruined), let me make that live for our US cousins, that's $11000!
and a tenner says it'll need crank seals sometime this summer.

Seach back far enough and you'll find posts from me trying to talk myself into buying a £4750 standard Rothmans mc28sp along with a ton of posts trying to talk me out of it.
I listened, Banshee learned a harder way....your call.
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