Even though an MC28 will struggle to ever make over 55hp (in the real world, not the daydreamers' world!) with a standard card, if you do set about properly modifying it you will need all the adjustment & special bits you can lay your hands on. HRC jet kits are selling for £200~300 these days. Have a look on Yahoo auctions & you'll often see a box of goodies with a dozen bids or more going for 30,000+ Yen.
Remember, Honda was long past looking for performance when the 28 came out, & the whole bike was softened for the street. The carbs are a bugger to work on (try adjusting an HRC needle in a set, then do it on an MC16~MC21 & you`ll see what I mean), the suspension is soft (although the SP front is a good cartridge design), the Pro-Arm flexes (in-built passive steering), and the ignition is flat.
A 300`s not going to have much impact unless you get an HRC card, & even then (again, in the real world) you'll be lucky to see much over mid-60`s. Still, at least with a standard PGM-IV the chocolate pistons might last a bit longer.
Hmmm.... let me think.... 300 kit, £1200.... Tyga pipes to fit the 300 barrels, £500... HRC card, probably £200+.... all for an unreliable 65-68hp!
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