From a press release issued by Proton Team KR:
BIRTHDAY-BIKE PROTON KR GOES BACK TO LE MANS
One full racing season after the Proton KR V5 first turned a wheel at a racing circuit, the latest version of the maturing 990cc racing prototype returns to the same track as a fully fledged racer … with an all-new sound to shatter the French countryside.
The changed exhaust note is the result of revised engine firing order, new since the last race, and reflecting continual updates and developments. This year’s Proton KR is much different from the first prototype. The latest machine, still in fast-forward development mode, has carved-from-solid framework, and for this race also new bodywork.
It was in practice for last year’s French GP at Le Mans that the brand-new Proton KR was fired up for its first outing anywhere except an airfield runway. The mellow howl left onlookers spellbound … but the bike was still too new and too raw to race. The pioneer riders reverted to the trusty 500cc two-stroke for the GP.
The new four-stroke raced only two weeks later, and quickly went from troublesome infant to promising youth. The first race finish was quickly followed by the first of a series of points, and by the end of the season the KR V5 was challenging the lesser Japanese factory bikes.
For 2004, the England-based team took another bold step forward, with radical chassis developments, inspired by F1 and using aerospace technology never before seen on a motorcycle. The engine had to be revised to fit within the compact new frame.
The new machine first raced at the opening round in South Africa, and the chassis was an instant success. Engine teething problems notwithstanding, rider Nobuatsu Aoki achieved a first-race finish. Two weeks later, Aoki claimed the Mk2 machine’s first championship points, finishing 14th in the rain-hit Spanish GP at Jerez.
Since then the programme has been hectic, reflecting the constant year-round development work at the Banbury factory. Two days of testing at the same circuit yielded encouraging information about a radical change to the engine’s firing order, and both Aoki and team-mate Kurtis Roberts will be using the different-sounding new engine at Le Mans.
Team principal Kenny Roberts explains the changes. “I came to realise that our original firing order was causing problems into the corner and in mid-corner speed, because there was too much back pressure from the engine braking. It made the slipper clutch too sensitive – we were always adjusting it. And it cost us time, especially as the race progressed.
“We changed the firing order without changing the crankshaft – only the camshafts, and the riders noticed the difference immediately. It’s better into the turns, and easier to ride.
“It’s still very new, though, and at this stage the engine power is no better and maybe not quite as good as the other firing order,” continued the former triple World Champion. “That’s probably something to do with the exhausts, and we’re working on that.”
Expert observers will also notice small but significant changes to the Proton KR V5’s bodywork at Le Mans, with a redesigned cowling that improves performance in every area, including penetration, cooling and internal airflow.
“To the naked eye, it’ll look much the same. But if you saw the old and new fairings side by side, you’d see differences,” said Roberts. “The development is in the detail.”
The French GP is the third of 16 in the season, but only the second for team and class rookie Kurtis Roberts, second son of team owner Kenny, and younger brother of 2000 World Champion Kenny Jr. Kurtis dislocated his shoulder in pre-season tests, and the injury forced him to withdraw from the opening race in South Africa.
“We’re hoping for a dry weekend, so we can get Kurtis up to speed, and carry on testing the new Dunlop tyres, to push development forward in that area,” said Kenny.
NOBUATSU AOKI – A YEAR OF INTERESTING ADVENTURE
The new firing order felt a lot different, and was especially better into the corners. It shows how the team is still working. The last year since we first rode the four-stroke at Le Mans last year has been very interesting. At first the bike was quite difficult, but it got better quite quickly, and by the end of the year it was enjoyable to race, and to get some results. For this year there is quite another step, with the new chassis and other changes, as well as the tyres. We are still developing new things all the time. The new engine should help us at Le Mans, where there is such a lot of hard braking.
KURTIS ROBERTS – GETTING THE LAPS UP
I got some more laps in at tests in Jerez, which is good. I really have so little time on the new bike and the Dunlops, so I’m still getting the feel of them and trying to get up to speed. The new firing order is definitely a step in the right direction. You can brake deeper into the corner, and the back end doesn’t step out of line so easily. As for Le Mans, I know it’s in France, and that’s about it. I’ve never been to the track before. This whole season I have to go about it step by step, and this is another chance to get some more laps done.