Chris, who shipped the bike back from Italy for me was stopping at Biggelaar on the way back to England and we took the decision that it was best to take the opportunity to have Toine gauge the condition of the bike (he has built a 998 and my other 749R Supersport motor).
We found that the motor needed a refresh: because the bike had been run without valve springs (they are very weak and just hold the valve shut, but the motor can gain a percent or two more power) the cams needed replacing. While the motor was apart, Toine found that there were a few unique parts inside the motor.
The gearbox is unique to the 749RS. It is a 4 dog box like the 999RS but has a unique first gear and mounts to the engine casing in a different way to either the 998RS or the 999RS. The alternator/generator is slightly different to the 999RS, having the same sized housing as the road unit but smaller windings - similar to the 999RS generators. The 999RS requires a spacer to mount the generator - the 749RS generator being deeper, does not.
Also of some interest is the choice of cams used in this motor and all engines run by Caracchi. Rather than using the 749RS/Supersports cams, the team used the 504 inlet cam together with a 749R exhaust cam. The 504 has similar lift to the 749R and RS cams and duration between the two. It's possible that the revised cams gave the engine greater flexibility throughout the rev range rather than the peaky, long duration Supersports cams, maybe the power is produced at lower revs with obvious implications for engine longevity. Something to investigate.
Thanks to my friends at ducati1.de, I have more photos of the RS.
The Breil bike is shown in some detail at www.ducpower.de. This site has the well-known publicity shots from 2004 but also has more detailed shots of the bike with the fairing off. The Breil motor clearly shows the titanium belt adjusters used on the Caracchi bikes.
The Caracchi bike was raced in matt black (2006), flat white (2007) and a red and silver scheme in early 2006. ptiteducat captured the bike at Magny-Cours:
Easton had some interesting moments on the bike. Phil Jessop told me that Easton commented that the bike was not as powerful as the Lloyds/Riders/JHP bike he campaigned in BSB. If the WSS bike had been running the 504 cams at this time, he would have been 10-15bhp down compared to the Y4 equipped motor.
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