Cycle News - Archive Issues - 1970's

• Yoshlmura Z-l Continued from page 13 the Production class. I sat up and shifted into fifth, letting the Z-l slow to the same speed as the 750. The rider on the 750 was all tucked in, but rolling it on in fifth gear, still sitting up, I just. pulled away from him. I could pass him on the straights with about a 20 MPH advantage. The corners were a differen t story. The bike still weighs in at some thing approaching the stock figure. Everybody has their own method of modifying the Z-l frame and all of them seem to improve things. I was asked not to divulge what the Yoshimura folks did to theirs, but it doesn't seem to matter too much. Kawasaki has prepared a Production racing version of the Z-l and made small changes that seem to work as well. Both sets of modifications were aimed at improving support of the swingarm and steering hand. The Yoshimura bike doesn't wobble excessively. That is to say that it never wobbles so much that you have to ~hut off. If you're like me, you might sometimes decide to anywaY,-though. It handles considerably better than stock; perhaps the Koni shocks help some, too. What seems to Jimi t the Z-l in corners the most is the tires. Ground clearance was adequate for me. I could just nick the track in the last turn at Willow where the tum tightens up after the high-speed sweeper. DuHamel, of course, had been dragging all sorts of pieces. (They had to make up a special alternator cover for him.) I don't see how he does it, but then I never expected to. The tires are the best available, and they still aren't too enthusiastic about keeping all that weight from going the direction it chooses. I found that if I was careful about rolling the tmottle on while exiting the turns, I could keep the rear wheel from spinning and doing the One Great Leap Sideways. I still had to go more slowly in the turns than I am accustomed to on the 750. The front wheel would move over IIrst with the power off, and driving out of turns with the power on, the rear wheel would get antsy and hegin to creep out when it had enough throttle. I usually found myself going considerably slower than anyone around me. At Laguna Seca, Yvon was going faster than anybody, everywhere. The man is so comple te ly in con trol of a motorcycle that it defies understanding. That I felt like such a porpoise on the same machine only amplifies the feeling of awe. The stock brakes are not nearly strong enough to deal with all that weight and speed. That fact was driven home fairly soundly the following week at Orange Coun ty International Raceway. After six laps, the rear brake, which had been tight at the beginning of the race, had used up all its travel, and the pedal was bitting the' exhaust pipe. The front wbeel is stopped by the stock single disc, something that anyone contemplating breathing on his Z-l should change. The Kawasaki optional dual disc would have made the rear brake last longer and the bike stop better. With the single disc I was shutting ·,ff very early. The Yoshimura udragon" version of the Kawasaki Z-l proves several things. It confirms the enormous performance poten tial of the Z-I, and it says something about the inherent strength of the Z-l engine, since the modified 903's have apparently been quite reliable. It demonstrates that the worst of the stock wiggles can be removed fairly easily (and probably should be). And it shows that the stock brakes, adequate if nol exceptional for street use, are not what's needed to anchor the big bike if it's being thoroughly wrung out. Yoshimura is going to he producing two hundred lOOOcc versions of the Z-I in time for next year's racing season. In addition to a hairy engine they will include a special seat and tank and an exhaust system. Not too many people want the bike or should be turned loose on one, but for the man who wants an ultra-high performance street machine and can handle it, the 1000cc Yoshimura Kawasaki should be singularly appropriate. • SU RCHAIN WINSACiAIN ANDACiAIN ANDACiAIN ANDACiAlN ANDACiAlN • . 11II .... 11II t Riverside International Raceway and Mickey Thompson's 1st Annual RV Spectacular. The big winner? The Dense Lube Superchain, sweeping five victories in the motorcycle competition including AI Baker's pro 21 victory and championship best overall ET. Other winners were Rjck Henricksen, Sportsman 20, Jeff Brownjng, Sportsman 21, and Bill Silverthorn, Pro 22. Race after race, on dirt, pavement or the salt, Superchajn continues to prove it's the chain of winners. Chain failure is virtually a thing of the past. What makes Superchain such a winner? It's the only chajn like it in the world. Lubricated permanently from the inside, so chains don't have to run dry on dirt, robbing you of performance horsepower. Superchain runs cooler and cleaner-holds its strength. Never needs lubing. And, the same stock Superchain that's breaking all the records is ready for your bike now. Write for information. Dense Lube Superchain. JACUlALCORPORA110n Manufacturers/Importers/Distributors of Motor Sport Accessories 6337 Manchester Blvd./Buena Park/Ca. 90602/(714) 523-7660 More Power to the Wheel-from Jacwal Save mo.ney! Fight pollution! Help a friend! Give your mailman a break! Feel good! GALL 213-427-7433 Ask for the subscription dept. and tell the lovely lady to send a Cycle News' Gift Subscription to Little Freddie, Auntie Poobah, or Joel Robert for Christmas. If you don't have any relatives named, Fred, Poobah or Joel, you get to tell her who should receive a sub-' scription from you, including yourself. Remember, you are doubly blessed if you give and receive. Especially when you save $2. Confused? Call and be enlightened. . 19

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