Cycle News - Archive Issues - 1970's

.- inding the Superbike T~at lurks Withlu Those !I. ~ N .... Cll l!f > ~ '" 3: ~ w d > U By Art Friedman One of the biggest problems with Honda is that they make machines with incredible potential. They develop one or two individual machines for racing which prove the possibilities inheren t in their bike and then withdraw, leaving the person who is in terested in racing a Honda with a terrible sense of frustration. Even if you knew what to do, there is no way that you could get or make the parts that appear on the Daytona 750's, right? Wrong. Yoshimura Racing and Checkered Flag Customs can sell you a Honda 750 engine that can win Daytona, a 350 twin that will deliver 53 horsepower and be competitive against 350 Yamaha road racers, or an XL 250 that will put out very competitive power. They will do all this in with an engine that eases up on power and is surprisingly un-canimy. . The whole ttUng starts in Japan with a fellow known as "Pops" Yoshimura. Mr. Yoshimura is a wizard with four strokes. He produces increctible amounts of power from Honda motorcycles and cars, and he is now getting into the Yamaha and Kawasaki four strokes. (The latter is the 902cc double overhead cam model which hasn't even seen dealers in this country.) All the products that Pops produces are tested and proven on the flow bench, the dyno, and the race course. For example, the four-in to-one collector systems are very popular at the moment and so research has naturally begun in that area. The first thing that we were told had been discovered was that none of the other systems tested could produce as much power as the stock pipes without producing more noise. Yoshimura's pipe will, if it is produced. "The first thing that they discovered," said Dale Alexander, one of the owners of Yoshimura Racing, the importers, "was that none of the known formulas work. It is purely cut and try. The system that works the best is all unequal length." Probably, the best known Yoshimura MOLLY BLUE gives you more ~ .... than you expected to get .....fro;." a chain lube products is the 750 Fours that appeared puts out a claimed 78 horsies, and at Daytona in the hands of Gary Fisher seat-of-the-pan ts evaluation certainly and Roger Reiman and looked to be confirms the claim. It is a jet. preparing to smoke the troops when Before I rode Dale Alexander's they packed up. The same scene had machine, I was put on a stock 500 four occurred the faIl before at Ontario and that was in for a power-lifting. Power Grandstand trouble-shooting had it that melts away on the stocker by 8000 rpm. the cam chain woes experienced by the The Honda of Alexander will pull a 750's that won Daytona in 1970 were clean I I grand. As a matter of fact, at uncurable. This would seem to be true normal rev range, about 5000 or less, it until you look at the Junior circuit. Jimmy Chen hasn't been put out by engine failure at all and he rides a Honda 750 prepared by Yoshimura. The 750 does have problems, though, according to Alexander. The rods tend to give up the game if over-revved slightly. This problem is being researched at the moment, and a. cure may be forthCOming. There is another problem that the 750 has that makes it unsuitable for many courses: it wejgbs a lot. All that weigbt makes it killd of unsuitable for short twisty courses. Does Yoshimura have an answer for that problem? Yes: the 500 four. Whj!e it can't make the power that a 750 can, the 500 seems much more reliable and can take over-revving (as shown when the dyno popped out of gear) withou t pukillg its little heart out. It also is smaller so it handles better, stops better, goes around corners faster, and punches a better hole in the air. All of which ..... kind of makes the 500 the Yoshimura Secret Weapon. You can get a ready-to-beat-the-world 750 engine for SI 995 less carbs. A The Checked Flag Customs front end set up for similarly strong 500 will cost you with more bearing surface. SI200. Why the difference? "Honda has gotten better," says Alexander. There are less parts in the 500 that need to be replaced because of their quality or feels like the stock bike. His hasn't been strength. By comparison, a Yoshimura given the full treatment either, just the 350 twin cost $1300. basics: a cam and pistons. It still idles, Sounds great if you are a road racer too. If you want to go the whole or a rich drag racer, but how about the enchilada on your 500, there are 23 street rider? I was allowed to ride both parts that Yoshimura morofjes or Fujio Yoshimura's and Dale Alexander's replaces. This indudes goodies like a street machines. (Fujio is the son of six-speed transmission, alloy rods, and "Pops".) They aren't run-of-the-mill those neat CR carburetors. It also Hondas. Fujio's Honda is a 750. Except includes small items like a clutch cable for the dual disc hung on the front it for clip-on handlebars. looks stock. It even idles. But it also There are 30 parts for the CB-750 and even more for the 350 twin. THERE'S MORE THAN POWER If you are going to make your Honda capable of blasting by anything on the street, it would be handy to be able to deal with problems like corners and stop ligh ts. This is where Checkered Flag Customs comes into the picture. The only thing that they sell are items that the CB 500: dual discs and magnesium sliders bolt on the lower end of your front fork, but they make a world of rofference. A dual disc installation goes right on'and will put your Honda Four's stopping in the same league with its acceleration. Feel is also improved with the dual disc se t up. There. has only been one brake in our experience that has surpassed the Checkered Flag dual rosc and that other one Was a one-off prototype.. The dual disc has to be PORT.G - $15.00 and up HACIENDA SPORTS CYCLE 1114'12 HACIENDA BLVD. LA PUENTE, CA.(213) 968-6971 Boring - Wheel Truln~ & LaclngPorting - Competltfon Tuning 10-6 Tues-Sat .• Closed Sun. & Mon. Husqvarna Penton lockers Sales & Senice 6624 A"an';c, 8ell, Ca. (213)581-3983. Complete 1972 line-up on display at the VALLEY'S LARGEST, MOST EXPERIENCED RICKMAN DEALER These are those neat Kei Hin CR racing carbs. This batch will 'fit the 7Sq. Yours for a mere $375,00. • • KOLBECYCLESALES, INC. 22123 Ventura BI1(d. Woodland Hills (213) 348-7891 Racing Magnet9S for most everything. There is also a shaft with ten gears mounted on this board. 1) I , .., ,,

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