RC30 Rebuilding

front

chassis

extra

Front Wheel
Stock front wheel is 3" wide (x 17" diameter). Modern rubber is designed for an industry standard 3.5" wide wheel, so fitting modern rubber on a stock RC front wheel will pinch the tire profile and alter handling along with tire wear. For general street use this isn't too much of a problem, but for track days and aggressive street use it's less than good. This setup will also roach tires more quickly since it concentrates wear along a small band of the tire, promoting cupping.
Solution: Fit a front rim from an NC30/35, VFR750 (1994-1997), or CBR600F3. This is a drop-in replacement - your existing (stock) rotors carry over as does your RC30 axle.

Rear Wheel
Stock rear wheel: The original is 5.5" x 18" diameter. This was more of a problem in the 90's than now, since Dunlop is (now/again)making a D207RR 180/55/18 for the Harley V-Rod. Don't scoff - Dunluop are on record as saying this is the same 'RR technology as all of their other 'RR tires and it does work surprisingly well. If you like the 18" look, or if you just want to remain totally stock, use the Dunlop.

Alternative 6" x 17" wheels: Fitting a 17" rear rim will allow you to sample any and all of the current crop of high-stick rubber. There are a few extra steps to take with this route, though:

Ride height adjuster: The 17" wheel is smaller so the rear shock mount needs to be changed to maintain rear ride height. Maxton makes an adjuster if you can't find one of the original HRC units. Note that Ohlins shocks are ride-height adjustable and obviate the need for other parts.

Wheel Spacer: If you run a 6" wide wheel there is a good chance that the tire will rub on the swingarm, or chain, or both. This is a function of production tolerances in the wheel, swingarm, and hub, but also largely in the tire itself. Dunlop tires are notoriously wide for their claimed dimensions, while Michelins are narrower and Bridgestones narrower still. There has been heated argument on the RC30 list about the suitability of fitting spacers to off-set the wheel to the right and avoid interference. Most people claim they cannot feel the effects of a 2mm or 3mm spacer on the bike's handling left -vs- right, and note that the Isle-of-Man racers ran as much as 6mm spacers in later years (with longer replacment wheel drive pins) when those racers were using 6.5" rear wheels. Fact is, though, that a spacer is putting the rear wheel out of line with the front. I've run 2mm spacers when needed to clear certain Dunlop tires and there were no downsides for me, but everyone must make their own choice.

RC45 rear wheel: The RC45 wheel is 6" x 17" and bolts right on. Depending on your luck and your tire choice you might need a spacer to keep it and the tire clear of swingarm and chain.

Ducati sss rear wheel: CORRECTIONS - In the past six months I've seen far too many different (and often differing!) reports on what year/model Ducati wheels work on an RC30, what don't, and what needs to be machined in order to make them work. I think we're seeing the symptoms of Ducati's often-famous marketplace agility - changing details, dimensions, and oem sources in mid-model, mid-year. I said before to go in with your eyes open but now I'd say don't go in at all; they're 6" wide, notoriously soft, and probably need machining. There are too many other good options out there to fuss with this.

Bottom line on rear wheels is that Honda designed the bike with a 5.5" wide rear wheel and fitting a 6" wide unit makes the bike slower to respond and heavier to steer. Best solution (but expensive) might be to find a 5.5" x 17" aftermarket (PVM, Marchesini, Marvic, or Dymag) and fit a ride height adjuster. With this arrangement you keep the original light steering, are able to use the best rubber, and avoid the angst of a spacer.