Racing Review
RACING REVIEW
H-D'S XR-750 RACER
There’s nothing radically new about Harley’s new Class C racing machine, which the public got to see for the first time at a trade show run in conjunction with the Astrodome events. The XR-750, with innards basically derived from the 883-cc Sportster, is ohv and destroked to conform to the new 750-cc AMA formula adopted in 1969. Harley failed to get it approved last year, but the production lines have been humming merrily away to come up with the 200 necessary for homologation in 1970.
The model shown on these pages is in flat tracker configuration, but the major components are identical with the road racer’s. The frame is a full double loop, based on the factory KR road racing frame adopted in 1967, fashioned from 1-in. diameter, 0.065-in. wall 4130 chrome moly steel. The swinging arm is made from 1.5-in. diameter, 0.095-in. thick 4130. Pivot length is as short as before, but potential waggle is effectively eliminated by anchoring the arm in a pair of hefty pre-loaded Timken bearings. Front suspension is Ceriani; Girlings damp the rear. Pretesting at Daytona in January brought comments from factory riders Cal Rayborn and Roger Reiman that the XR-750 is more stable and handles better than the trusty KRs.
Bore/stroke ratio is still slightly undersquare at 3.005 in. by 3.291 in. Intake valve on the flow-tested, handcontoured XLR hemi heads (all 200 of them) measures 1 and 15/16 in., while the exhaust valve has been enlarged to 1 and 3.4 in. Standard compression ratio on the high dome pistons is 9.5:1. Cam timing has been subject to rethinking, and emphasizes long duration with mild ramping. For the time being, the XR uses a single diaphragm-type carburetor.
Racing chief Dick O’Brien said he’s pleased with initial tests, noting that the broad 4800to 7800-rpm power band matches the four-speed gearbox limitation quite handily. The bike pulls well from 3000 rpm without the burbles and flat spots that seem to have plagued previous KRs and XLRs. O’Brien demurred on a power figure, but conceded a hint: “62 bhp at 6200 rpm,” which is not, by any means, the peak rpm. The new formula has given the Harley racing effort a lease on life, the smiling O’Brien said. “We’re at the same degree of development with the XR as we were with the KR 8 or 10 years ago. There’s lot’s more there.”
BELL & BUCO AWARDS
Two major helmet manufacturers— Bell-Toptex and Buco—have posted contingency award schedules for 1970. Buco has posted $12,840 in contingency prize money for AMA Expert and Amateur riders using Buco helmets and face shields in the 1 970 nationals.
The No. 1 AMA points champion could claim $1000 of this purse at the end of the season, if he used Buco products during the year. Winners of a national points race in the Expert class could claim up to $250 for wearing the helmet and decal, and $25 for a Buco faceshield. The corresponding prizes in the Amateur class are $50 and $15.
Bell-Toptex offers $9900 in contingency awards for the AMA circuit—for the Expert class only. First place winner of a national gets $200, and 2nd place $50, if he’s wearing the Bell helmet. At Daytona, the prizes run $300, $200, $100 and $50 for 1st, 2nd, 3rd and 4th places.
Further, the winner of the AMA No. 1 plate in 1970 gets $1000, if, of course, he is sporting a Bell.
BERKSHIRE INTERNATIONAL
The two-day Berkshire International Trial has grown in stature year by year to become one of the most unique cross-country events in the U.S.
Its sixth annual running is scheduled for May 16 and 17, in the area around Middlefield, Mass.
It is patterned after the International Six Days Trial, and includes special tests as well as ISDT-type scoring of competitors, who must conform to a minimum average speed over hill and dale.
This year it becomes one of the qualifying events for U.S. riders interested in selection as U.S. entries for the 45th ISDT, to be run in October in Spain. Entry forms are being mailed to more than 1000 eastern enduro riders, with the first 400 returned to be accepted. A similar one-day event for West Coast riders—organized by the Prospectors MC—has already been run in the Mojave desert.
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The 1970 Berkshire will have teams representing most of the major distributors of off-road motorcycles, and probably include teams from the West Coast.
Scoring for the event features an unusual twist; use of computer facilities in Cambridge, Mass., by way of a telephone link from the Middlefield headquarters, for computation of scores. Dr. David Latham of the Smithsonian Astrophysical Laboratory in Cambridge is supplying the computer scoring program and facilities.
Latham will also be one of the leading contenders for a Gold Medal award in the event. He is an avid enduro rider, and past New England Grand Champion. Last year he won an AMA national enduro. He has innovated new, efficient systems for scoring enduro competition. For more information, call Allen Eames (413) 684-2262 or Bob Hicks (617) 774-0906.
PEPPERELL REDESIGNED
The four-year-old motocross course at Pepperell, Mass., traditional opening venue for the Inter-Am series, has been scrapped and will be replaced on the same grounds with an entirely new circuit.
The old one quite simply was getting worn out, as racing machines chewed into it year after year and exposed the rocky subsoil.
The new course will measure about 1.25 miles in length. It will be laid out to take full advantage of the rolling terrain and still provide excellent spectator vantage points, a characteristic for which it has been noted in the past.
April 26 is the opening date for the new circuit, with a full program of professional and sportsman motocross events. Other dates of interest; a CanAm professional motorcross on May 31, a big sportsman race on June 21 and the Inter-Am opener on October 11.
AFM (OF LA) SCHEDULE
The Los Angeles chapter of the American Federation of Motorcyclists (AFM) has announced its 1970 schedule of road races at California’s Orange County International Raceway. One race has already been run, but the remaining dates are May 17, June 7, July 12, Aug. 9, Sept. 13, Oct. 4, and Nov. 1 (the 3rd annual International Grand Prix). Additional information is available from James Manning (213) 937-2011.
KAWASAKI RACING $$$
A total of $500,000 has been offered as contingency prize money by Kawasaki Motors Corp., Santa Ana, Calif.
It is the largest sum of its kind in the history of American motorcycling. It’s a safe bet that not all of that half million dollars will be claimed this year, but it is still a remarkable gesture—setting a precedent that should help much to stimulate American racing.
The purse is based on winning performances by competitors riding the Kawasaki brand. The lion’s share goes to winners on the AMA national circuit, $349,500 in cash. But other branches of the sport are recognized, too.
Kawasaki-mounted winners of the Greenhorn and Jack Pine enduros would receive a new Mach III, valued at $1000. Kawasaki winners at Bonneville can tap into $34,500 worth of 100-cc Trail Boss machines.
Should a Kawasaki powered twowheeler raise the absolute motorcycle speed record at Bonneville in 1970, with recognition by either the AMA or FIM, <Te rider would get $25,000 in cash.
Other cash awards: $2500 to Senior main event winners of an Inter-Am motocross; $10,000 to the Inter-Am series winner, with all points being earned on a Kawasaki.
AFM road race senior main event winners can earn $250, and the winning of the overall high-point AFM championship is worth $5000. The same prize money will be awarded for similar AAMRR events and series winner.
NORRA-Baja 500: first overall, $3000; first lightweight, $500; first heavyweight, $500. Baja 1000: first overall, $5000; first lightweight, $500; first heavyweight, $500. Mint 400: first overall, $3000; first lightweight, $500; first heavyweight, $500. AHRA-NHRA drag racing is also allocated $5000 for certain events.
This naturally leads to speculation on which events will prove most fruitful to Kawasaki hopefuls. On the AMA national circuit, road racing, particularly on the tight courses, offers fair possibilities, although a Kawasaki Mach III rider would be giving away 250-cc displacement in the Expert class. In AFM and AAMRR road racing the prospects seem better, due to the 500-cc class delineation there. A 250-cc Kawasaki could do quite well at an AMA short track national with the proper rider.
The Greenhorn and Jack Pine are naturals, as Kawasaki’s 350-cc Single is quite well suited to the task. The same holds true in the professional NORRA cross-country races.
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In the Inter-Am series, which has yet to be dominated by either an American rider or a Japanese machine, chances are somewhat remote. But a dark-horse win by Kawasaki would be worth every cent the company would have to pay.
One can flatly predict a large run on those Trail Bosses at Bonneville, for class victories, but the $25,000 for an absolute world record will most likely remain untouched. That last one is a toughy to get, even with the most thorough factory support, by any company. Drag racing offers pregnant possibilities.
Riders interested in taking up the race for Kawasaki dollars would do well to contact the company beforehand to make sure they are meeting the proper conditions for winning contingency money. The main condition, of course, is that the victory must be achieved on a Kawasaki, but in some cases, such as drag racing, the wins and records require time slips and notarization.
It’s a grand gesture, good for the riders, and should do much to stimulate such support from the motorcycle industry. Someday it may be the norm.
SADDLEBACK PARK HILLCLIMB
A good sized crowd, enjoying beautiful Southern California sunny winter weather, witnessed Saddleback Park’s first hillclimb of the 1970 season. Trophies and cash were awarded to the victors, and participants came from all over the state to compete for these prizes.
A new “Matterhorn” was constructed to replace the original, as the previous slope had been severely damaged by winter rains. Vic Wilson, Saddleback Park director, had instructed the bulldozer driver to “Clear a swath down the side of that cliff over there so’s the boys will have a place to play.” The new run is only a few yards away from the old one, and utilizes the same steep grade and loose, rocky soil. Fortunately, rainy weather a few days earlier had packed the dirt down and left some moisture in the ground for better traction.
Highlight of the day was a “clean” by a woman! Sammie Dunn, a secretary for McDonnell-Douglas Aircraft, cleared the top unassisted, to become the first woman in the history of the Park to accomplish this feat.
Each rider was allowed four tries at the hill, with the rider going over the top or climbing the highest up the slope being declared winner in that respective class. Fastest time over the hill was a tie between Jerry Dunivan (650 Rickman/ Triumph) and Chuck “Feets” Minert on his trusty 441 BSA Victor. Rick Sandberg was victorious in the under 100-cc class, after several valiant, but futile efforts on his Honda 90. The 125 class was topped by TT scrambles star Ron Taylor on a Yamaha AT-1MX. Mel Cunha (Montesa), from Bakersfield, was the only 250 rider to make it over the top. “Feets” clinched the 500 class, while Jerry Dunivan also conquered the open entries. A round robin elimination final topped off the day’s events, with “Feets’ ” BSA Victor pop-popping over the hill faster than anyone else.
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The crowd seemed to enjoy the action, and many expressed a desire to witness more hillclimbs in the Southern California area. It definitely is a thrilling sport for both spectators and participants, while damage to those unfortunate riders who performed the crowdpleasing flips was confined to hurt pride and bent handlebars.
The spectators, as usual, wanted to be right in on the action, and several were treated to a big bore Triumph landing in their laps, but fortunately no one was injured. [o]Z
