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How was it so successful? Racing versions that much better? Nicky’s talent? What made the RC such a good racer, and did the style of track help?
 

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The Factory HRC RC51 Superbike does not share one single bolt with the production version. Literally not one. Everything on the Superbike was different. Different frames, engine cases, heads you name it all the way down to the bolts that hold on the bar ends are different. The only thing they really have in common are the bore & stroke numbers of the engine.

The bike was successful because it had millions of dollars thrown at it to win at all costs and with that came a commensurate level horsepower and handling. Every Pro rider that rode an RC51 Superbike had excellent results on it. You didn't even have to be that good of a rider to win on the RC51 Zemke, Edwards, Hayden, even Kurtis Roberts won races on it and while they are all Pro Racers I would not consider any of them to be top level racers like the aliens of MotoGP. Don't forget that they were also racing against 750cc Inlines as well...
 

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The Factory HRC RC51 Superbike does not share one single bolt with the production version. Literally not one. Everything on the Superbike was different. Different frames, engine cases, heads you name it all the way down to the bolts that hold on the bar ends are different. The only thing they really have in common are the bore & stroke numbers of the engine.

The bike was successful because it had millions of dollars thrown at it to win at all costs and with that came a commensurate level horsepower and handling. Every Pro rider that rode an RC51 Superbike had excellent results on it. You didn't even have to be that good of a rider to win on the RC51 Zemke, Edwards, Hayden, even Kurtis Roberts won races on it and while they are all Pro Racers I would not consider any of them to be top level racers like the aliens of MotoGP. Don't forget that they were also racing against 750cc Inlines as well...
And Ducatis
 

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highly strung yes, crankcases were the weakness i think, but not slow when they were in one piece, even Pier francesco Chili's "privateer" bike would regularly top the speed charts
 

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They didn’t share anything with the factory SPW’s but many privateer complete racer package SP’s did very well in competition around the world. Nearly all had different cranks, strengthened cases, rods, pistons and cams plus modified gearboxes. This on top of significant suspension upgrades.
Any bike with that much development and spend can be competitive. HRC helped out with fitting the SP1 race kit based items for the SP2 For homologation rules. Swingarm, forks, headstock, TB’s etc.
 

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LDH nailed it, no correlation to our street machines at all beyond the moniker. And even still, our SP's aren't what I'd call a slug...even with me on the seat.:wink2:
 

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It might be interesting but bear in mine the RC51 superbike IS a race bike and the Beemer and GSXR are street bikes. There are more differences than you might think. Probably 50 to 60 pounds in weight for starters.
 

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Hayden had some laps in the 1:27 range at Laguna Seca in 2001, and Cycle World did a test of a BMW HP4 and a Ducati Panigale around the track in 2014 i think, with former AMA Superbike rider Eric Bostrom, and he did 1:33:09 on the Beemer. Guess that says it :)
 

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They didn’t share anything with the factory SPW’s but many privateer complete racer package SP’s did very well in competition around the world. Nearly all had different cranks, strengthened cases, rods, pistons and cams plus modified gearboxes. This on top of significant suspension upgrades.
Any bike with that much development and spend can be competitive. HRC helped out with fitting the SP1 race kit based items for the SP2 For homologation rules. Swingarm, forks, headstock, TB’s etc.
Do you know how they strengthened the cases?
 

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I just read this, and shortened it up from Cycle World, but it does explain some of the differences form MotoGP to Superbike, to street bikes:

For World Superbike, the homologation procedure begins with 125 machines and by the end of the first year of participation, 500 must have been built, and by the end of the second year, 1,000. A price ceiling for the homologated model is set at 40,000 euros (approximately $45,500). Ducati’s Panigale V4 R gets its Superbike-legal reduced 998cc displacement from a shorter stroke.
Production methods that are economical for building 500 bikes are different from those for building a prototype. Yamaha’s MotoGP bike engine crankcases are machined from solid in a 70-hour process. Honda’s RC213V cases are sand-cast. But for quantity production in the hundreds or thousands, it makes better sense to die-cast the crankcases, cylinder heads, etc. As a result, parts produced in larger quantities tend to be both heavier and weaker.

MotoGP engines are required by tech rules to last through three-plus events each (each rider has six engines with which to complete the 19-race series). To achieve this, component quality must be the highest possible. So, for example, crankshafts will be forged from a low-defects vacuum-remelted aerospace steel alloy similar to 4340M and the job will be done by a specialist supplier. A production bike, by contrast, is expected to last through a normal road-vehicle lifetime at a street-legal stress level.

Performance levels also differ. While it is known that Ducati’s MotoGP V-4 can operate safely to 18,000 rpm, where it may produce as much as 275 hp, the one-liter production V4 R homologated for World Superbike, even though having the same bore and stroke of 81.0mm x 48.4mm, is rated at 221 hp at 15,250 rpm. Redline in sixth gear is 16,500 rpm, which says, “Eat your heart out, Kawasaki” to its most obvious World Superbike rivals, whose 13 percent longer piston stroke makes such high revs harder to attain reliably.


In the V4 R, lightweight titanium connecting rods replace the steel rods of the V4. The pistons are described as “molded” (i.e., cast) of “box-in-box shape” and as having the pure racing fit of a single compression ring plus an oil scraper. The lighter the reciprocating parts can be, the lower become stresses and bearing loads, allowing reliable operation at higher rpm. The V4 R’s crankshaft, like that of the V4, has Ducati’s MotoGP-originated 70-degree-offset crankpins but is almost 2-1/2 pounds lighter. It turns on three of what are cryptically called “brass bushings.” Hard brass bushings of the kind common on railroad axles of 1900 would be strange indeed for a 15,250-rpm internal-combustion-engine crankshaft.

What this may mean is that, as in the case of Honda Formula 1 engines, the old heavy-duty form of bearing called “copper lead” has been revised upward in strength. A copper-lead bearing derives its fatigue strength from a matrix of copper, which is impregnated with lead to provide essential “embedibility.” That is the softness that allows the hard crank journal to drive potentially destructive wear or contaminant particles into the bearing surface, rendering them harmless. Therefore the “brass bushing” probably means a bearing whose endurance comes from brass being stronger than copper and whose embedibility is provided by infused softer metal. It is almost illegal even to utter the word “lead” in today’s heavy-metals-free world, so other soft metals such as tin, zinc, etc. provide the necessary softness.
In the MotoGP engine, a train of steel spur gears drives the camshafts, but the production V4 and V4 R are given less noisy and cheaper cam drive by silent chains. Why the difference? With gears it is easy to maintain accurate valve timing through hard racing use, a task that is harder with a chain that has perhaps 100 links and pivots.

The purpose of a homologation special is to make legal for racing those elements essential to the highest performance but which would in mass production add needless cost, being superfluous to the requirements of even the most spirited of everyday riders. Therefore, in a sense, such bikes are designed by the rule book. I expect most V4 Rs will go to actual race teams.
 
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