Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles
Issue link: https://magazine.cyclenews.com/i/125500
QUESTIONS AND II, ANSWERS the Answer Man SeDd JOur qa.stl.. s to TIl. AIlS_ .... Car. of Cycl s, Bos ea, LOlli Buell, Calif. Sony, wlu 011 lUll do.. IIOt all_ us to seod IDdlvidual replies. QUESTION: What changes if any, can I make in my engine to run at Bonneville and maintain a stock classification? J.P.-Altadena. ANSWER: Any change such as compression. cam s, Darting and etc., is quite legal as long as there are no alterations to the engine's original design, such as changing from push rod to overhead cam system. You must also maintain original disDlacement with no more than .040 overbore. QUEmOI: 1 have been running NGK plugs bat wisb to change to another type. What is the equivalent to B9E in other brands? W.W. - Pomona. AIISWER: A utolit e-A 660 3, CbampionN-57R, Lodge-RL49, KLGFE280, and Bosch-W310T 17. QUEm 011: 1 am 15 years old and own a Hodaka. 1 am interested in competing in Hare and Hound, enduros, trails' and maybe MotcM;ross. I would like to know how to get a number. Do I need an A.M.A. or some other type of license to compete? 1 am going to start mixing castor oil with my gas and would like to know what gas to oil ratio I should change to. I am now using a • 20:1 ratio with RPM S.A.E. 30 oil. What is the dillerence between hare scrambles and regular hare and hound? What is meant by bore and stroke, torque and oil dampened springs? How do you pronounce Husqvarna? B.K. - Burbank, Calif. AIISWER: To obtain a number and compete in any event of the type you describe, a membersbip to the A.M.A. will be required and if the event bas prize money awards, you will need an A.M.A. competition license. A purchase of the said license will give you a number in the A.M.A. competition ranks. The recommendation for a castor oil aod gas mix ratio will vary from 20: 1 to 53:1. I suggest that you run 40: 1 or greater for competition. Be prepared to tear down your engine's upper and for carbon removal quite often. SOme riders do this after each day of the engine's running. Tbe major difference between Hare SCrambles and Hare and Hound events is that scrambles are on a closed course of approximately five to ten miles, while the Hare and Hound is held over any course, preferably cross country at least 40 miles in length. The bore of an engine is the diameter of the cylinder bole in which the 1 Distan travels. An engine's stroke is \ the distance a piston travels from ,top dead center to bottom dead center. The torque of an engine is a reaction force equal and opposite to the crankshaft rotation. The entire engine tends to rotate around tbe crankshaft. This force is measured in ft. lbs. Oil dampened sDrings are ones enclosed wi thin a bousing that incorporates oil for bydraulic dampening. Tbe oil may be forced tbrough small boles or slots, controlled by valves made of balls or discs and closed by sllrings. The control of oil now slows the springs' movement and they are thus referred to as oil dampened springs. Husqvarna: Husk-var'-nuh. QUEmON: The slide in my carburetor is constantly sticking. What can be done to correct this and what caused it? B.D.-Canoga Park, L.A., Calif. AISWER: The common reason for a sticking slide is the warDing of tbe carburetor. If the mounting studs or bolts are tightened unevenly and the engine becom es hot, the carb body will distort from its correct shape. Even when cooled down tbe carburetor does not return to normal. I believe the only correct way to cure tbis is to purchase a new slide or apply a thin coat of wax gilt -mfg. by Connoisseur studio of Louisville., Ky, and obtainable in art stores,· to the old slide. Placing the slide in the carburetor and working it up and down will reveal the points at which contacts are made between the carburetor and slide. With a piece of fine emery cloth the slide may be buffed down to a working tolerance that will prevent future sticking. Do not rely upon the signs of contact on the old slide before awlying gilt, because many of the marks may have been caused by small pieces of grit. or dirt that became wedged in the carb's barrel and caused the scoring marks. If the carburetor is warped severely enough to cause contacts at more than half the ·barrel's· diameter, then purcbase a new carb or replac em e nt part. QUEmON: I have read many books on motorcycle maintenance and most of them were written and printed in England. In these books they recommend paraUin as ideal for cleaning engine parts. Paraffin is a wax, bow do they use it? ANSWER: am definitions of the word Paraffin are different. In England k.erosene is called paraffin, here it is a wax as you mentioned. SO, of course use tbe kerosene for that is what they mean. 7~7e44 7w.p44 11726 s.u ....Ica Blwd. W.st LIlS ARceln PII: GR 3-1101 TA E ALTY! 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