Cycle News - Archive Issues - 1970's

.... N " New Stuff & Things I SAME OLD GRIND? Not with this bench grinder from Flanders_ In fact, it will grind more than benches. You name it, it'll grind it. Power specs: 1 hp at 3500 rpm. Direct drive. Electric starter: 8·amp single phase pole motor with sealed bropze bearings. Comes complete with two grinding wheels and a brush. 847.95, guaranteed. Part No. R 675, Flanders Co., Box 2297D, Sector Q, Pasadena, CA 91105. GIFT FOR ALL The American Motocross Team has just re1eased the new official 1972 calendar which features outstanding photographs of the top Europeans (and all the Americans) - in the 1971 world motocross campaign. Superb shots 't>f Adolf Weil (Mr. April), Torsten Hallman on a Yamaha, an embarrassing one of Bengt Aberg in the air with a foot stuck out, and a mug shot of Barry Higgins scowling. Get it from the AMXT for a $3.95 donation and help our boys overseas. Also, embellish helmets, gas tanks, motor homes, hatever, with AMXT stickers. They're vinyl and will last a long time. Two for $I, one of which will mount inside windows. AMXT, Box 3276, Hollywood, CA 90028. They really appreciate the help. ~ ~ , = / TUNE ALONG WITH ROD Rod Breaker's favorite handy-dandy tuning tool, Micro-Time, is available as a kit. It comes with a continuity tester (which looks suspiciously like a wire, a light bulb, and two alligator clips)' and complete instructions. If you read The Home Workshop, you already know the instructions. Anyway, the measuring device is as tough and simple as the brat next door, and will last much longer. It fits any size spark plug hole you can think of. In short, it will work on virtually any machine that is capable of making noise. $15.95, at more hip dealers. Compu Industries, Inc., 932A N. Brand Blvd., Glendale, CA 91202: .-- D $1.39, YET Saratoga Enterp;ises of Beverly Hills took two of the most overused words in the English language and tagged them to their new wondertool, the Super Swinger. The photo above is a symbolic tableau of the' tool's uses; that is, the Super Swinger (center) replaces all those forlorn-looking antiques that surround it. Far out. For $1.39, it might be worth taping to your downtube so you can defend yourself from the next rabbit attack while out trailing. then use it to skin, clean, cook, and eat your prey and pick y.our teeth afterwards. Look for the Super Swinger (that name!) at supermarkets, sporting goods, auto supply stores, cereal boxes.... (Cont'd. from page 2) cool air' blowing on that hot exhaust flange ...But the nice thing that with the length of the chambers needed today, anyone that got within a foot of your rear wheel would get poked in the eye with a stinger that is sticking a foot out...Well, maybe you could put a red flag on th e end." WARREN HULBERT, Northridge, Calif.: "The only reason I can see for not having the pipe at the rear (on some bikes) is styling. No one would buy the darn bike ju st because it looked so .much different than the usual." Finally, DALE GUTHRIE. after agreeing with the exhaust-must-havecool-air theory, added: "A straight exhaust pipe is not necessarily more efficient than a curved one. It is true that curved do increase viscous effects and this absorb power; the effects are insignificant as long as the bends are not sharp enough to cause large reflections. This is because laminar flow does not exIst in the first place. Also, in the case of the expansion chamber, both sub· and super·sonic flow occurs. "In a four-stroke engine, continuity of fine rather than straightness of line is important. With the valve in the middle of the exhaust port, strong, planer front shocks cannot be developed. The exhaust pulse is ,rather long and of low pressure. "On a two-stroke engine a straight header pipe would again not be optimum. :rhe exhaust port opens from the top down, resulting in a shock wave that is not normal to the exhaust pipe. Leading with its upper edge, the shock front expands into a larger cross·sectional area (and thus volume) and is weakened. this phenomemon accounts for a downswept pipe being more efficient than an upswept pipe. "Reversed barrels and heads have been tried on four·stroke dra9 and Bonneville bikes with no signoficant success that I can recall. Keep your spokes tight." TALKING CARBS Dear R.B.: , I own a 1966 Bultaco Sherpa 175, that I bought a year ago from some people who took off the stock Amal carburetor and put on a German one called "Fischer". The main jet is to big and I can't get a smaller one because no one makes them. Can you tell me where to get one or where I can get this one made smaller if possible. All I know is that it says Frankfurt Moblegard on it, I'm not sure of the second word because it was worn partly off. Can you give me any information on this. ERIC LYNN Palos Verdes Peninsula, Calif. DEAR ERIC: I'm afraid you got me on this one, "Gott in hemill, vot ist it mitt dis vergasser" this is one I haven't heard of as yet either. My first suggestion to get rid of it and get a regular carb or pick up a Mikuni, these seem to work good on just about anything you put them on. Personally I am against altering jets in any way, my advice has always been to purchase the correct size, a reamered out jet is worth less as it does not correspond with any information stamped on it and it can lead to some pretty frustrating tuning, maybe not by you, but by the next owner of the machine who takes tf:1e stampin9 on it as gospel. In your case, this information is worthless, I realize y:ou would be happy to purchase the correct jet if you could find out where so your next best thing is to obtain some numbers drills beneath' the size you have for the orifice. Then solder the jet closed and bore it out the next size smaller, put it back in the carb and try it, if it is still too rich, try it again, but always go down-one step at a til'(le, don't try to save time by going small and working your way up, you might not make it and it. takes more time to replace a piston than a main jet. On many carbs. the form of the jet around the orifice both inside and at the bottom often have a lot to do with the flow' of the fuel, so when soldering it up, take care not to change this if possible. Try to solder just the distance that the hole remains the same size. I reiterate, I don't approve of th is, AMXT CONTRIBUTORS: • POOP In the past, we have mentioned that the Elsinore Grand Prix is through, finis, kap.ut. We rec~pit~late: Don't give up on It yet. There s still a faint pulse... • • • Great news for racing fans is that capitalist pig·rancher J.C. AGAJANIAN and associates have purchased Ascot Park from its former owners! Now the famous Gardena, Calif. facility will close down for long-awaited refurbishing, refinancing and a thorough review of the hot dog. ingredients. The new owners plan on investing enough money to bring Ascot up to a new standard for race places, such as the sport and LoS Angeles deserve. • • • Yamaha International has' struck back at striking dockworkers by airlifting parts to the States. A recent shipment that arrived in Los Angeles was worth $150,000. That shipment should be at your dealer by the time your read this. • • • Youngish stuntman STEVE DROSTE, doing stunts for TV crews a few days before the December 11. "Cycle Circus" brouhaha, managed to loop his bike and break an ankle. Distraught manager GENE HARTLINE, already obligated to the upcoming show, signed none other than DAVE ALDANA to take his place. While cast-clad Droste kept the crowd entertained with wheelies and seat stands, Aldana jumped six cars, split a gas tank on the landing, and exploded flames. Naturally, Dave was unhurt and later that night jumped another six, then seven cars. Hartline beamed, "The crowd went nuts." Then he added that Dave, looking for a ride since BSA dropped the team, may sign to do more of the same. Aldana has more balls than a Christmas tree and may have found his calling. r:: - By Rod Breaker COSTAL MOTOR SPORTS, Corpus Christi, Tex.; DONALD BRIDGETT, St . Charles, Mo.: JOSEPH P. McCAMLEY. Jr.: Morrisville, Pa.: D.A. FRYER, Baltimore, Md.; E.J. YOUNG, BUCkner, Mo.; JAY YOAKUM, Artesia, CaUf.: BILL HAGUE. Pawhuska, Okla.: DON WHITCOMB, Bowie, Md.: FRANCIS G. BLAKE... Anaheim, Calif.; DANIEL L. DeVOLLD ,-ambridge, Ohio: JAN GRANDIDIER La Puente, Calif.; ROBERT B. HARMON, Chelmsford, Mass.; DENNIS J. KENWA, Portland, Oregon: MIKE McPIKE. Vandenberg AFB, Calif.; WILLIAM J. McCOMB JR.; Philadelphia. Pa.; MIKE MALTESE. Howell, N.J.; LENDALL TERRY. Santa Mana, Calif.; DARLENE WARD, Charlotte, N.C.; SHAWN TWITCHEL~t Riverton. Utah: D.E. WRIGHT, Elm Grove, wis. • ROrON rCont'd. from page 20) the above mentioned lack of a sense you really have to watch yourself going down fire tra1ls and dirt roads. The stability of the machine and the ability of the suspension to soak up Just about anytbing you run over gives you a lot of confidence. You ftnd yourself not worrying about failing, but worrying about over- shooting the next turn. The brakes, if anyth1ng, are too good. They are not overly sensitive, but requ1re experience to get the maximum without getting toto trouble. In woods the bike is WlbeUevable; getting through the tight stuff like a machine half Its size. The ready power, always having Just the right applicaUoo gear-wise to the rear wheel makes for some revelations the first time you hit the woods. The Hokon is an American motorcycle, 'being bu1lt in Keene, New Hampshire. When It reaches the production stage, it could have about as much effect on enduro riding as the Chapparal had on Can-Am sports car racing. Cycle News will hopefully have a more complete report on the production version of the machine as soon as It is ready. of speed, '" but it seems your only way. out. I am assuming that you are checking it at full throttle, the main jet only takes effect between three-quarters and full throttle, if your problem is not here, you must look elsewhere. ROD Dear R.B.: I've been looking for somebody who makes frames for small bikes. I own a 1968 Honda 125 SS twin. They put this engine in a pressed steel frame and I don't like it. I wrote Roehr Bros. and got a notice that they were going out of business. Could you suggest somebody who might make a frame for this model? Also include a price if possible. Just to give 'lne an ideal of what it will cost to build it. Any time you spend will be greatly appreciated. PlliLLIP RICHARDS Leisure City, Fla. To Leisure City. Fla.: As this particular model of Honda is in very short supply, I doubt if you will find anybody who makes a frame just for it. As most frames are Jig-Welded, the expense of setting up a jig has to be based 0 n th e p rem isse th at a good number of the frames will be sold to compensate for the expense and to produce a profit margin. You might be able to contact some of the frame manufacturing companies such as Trackmaster or possibly someone locally by checking in the Dixie Cycle News and they might be able to help you out if you send them some exact measurements of your engine, but I think you would get better results if you had it done locally where you could take the engine into them so they could build a frame around it. As for cost, I can imagine that it will run you from $200 to $400 depending on how much labor is involved. As this would require an investment that is equal to or more than the blue book worth of the machine, it does not seem to be the way to go. On the other hand, you might check around the local shops or if you have any motorcycle breakers (salvage yards) in your neck of the woods, you can check for a frame from some other model or even some other brand that you may be able to slip your en9ine into without too much hassle. It may require making different mounting brackets and such, but if you have the work done by a reliable shop, you will probably be happy with the results. ROD • • Since Papa Wealey dreamed up the idea of my answerin9 questions sent in by our readers, everybody in the office has been calling me the Ann Landers of the morcyde set. This is something new new to me. I'll probably butcher it up, but I will try my best to help you out if I possibly can. I'm not about to admit that I will probably make some mistakes, but keep in mind that "to erris human". Also try to keep in mind that my main responsibility is Malfunction Analysis and Correction. I gave up race tuning some years a90 so try to avoid such questions as "how can I get my Alstate MoPed to 90 fast enough to keep up with the freeway traffic?" (Trade it in), but if enough of you ask, I'll dip into it now ana again. When definin9 a problem, try to give as much information as possible. it is difficult enou9h tryin9 to cure a problem without the machine, it is next to impossible without the pertinent information. One of the trade magazines once received a letter to their Q & A column, "Dear Sir. I have a 1965 Honda. it won't run, what's wron9?" Had it been me, my answer would have been "The Nut That Holds The Handlebars." . Anyway, I think you get the idea, I wlll try my best to come up with the right answers. but all I ask is that if I blow it, please for9ive me. ~ w Z w oJ U >- U

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