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/125568
• "" "" r- ~ '" .. e, co to .... .... 0> QUESTIONS AND • • * ANSWERS * .. * ~ By Th e Answer Man The copyri ght will only protect your e nginee ring drawings from reproduction. It does not prevent a perso n from manufacturing the objec t in the drawi ng. The patent is to protect you from a nyone mak ing or 's e ll ing your inventio n. fIJ '" "" '" -e en = ~, ~ QUESTION: ....:J U >. o QUESTI ON: I am i nterested in drag racing and would like to know the current reco rds cer tified by A.H.R.A. I s i t possi ble for me to obtain such a list? T. T.-Rochest er, NY AN SWE R: Sure, just s end a reques t est to: A.H.R .A .; 1820 W 91st P lace , Kansas City , Missouri, 64114. QUESTION: W here can I con tact 'someone who can give me inf orma ti on in regards to a Vin cent" Meteor Comet ," the 500ccsingl e cylinder machin e? W. F . - Chula Vista, Cal if. ANSWER: W su ggest yo u try Mr. e Marty Dicker son. 292 Beyer Lane , Thousand Oaks , Calif . QUESTION: I have designed a new smog control device for motorcycles, bot h two-and fourstrokes. I wi sh to take the necessary steps to protect my ideas and would like to know which is the corre ct method to apply, copyright or patent. How are they different? M.B. - Van Nuys , Calif. ANSWER: .F'trs t le t me s ugges t you obtai n the services of an attorney, for if your device .is worthwhile. the cost will be well spent for qualified expe rtise. 1 have a 650cc Triumph that vibrates rathef severely. I intend to overhaul the engine and w 0 u I d like to have the crankshaft balanced. 1 was told I would have to specify a "bal ance hat facto r" to the machi ne shop. W are the figu res I should give them? A. P. - El ko, Nevada. ANSWER: Number one , be sur e and deliver to them all components that are a part of the re ciprocating mass . Crank , rods, ins erts . pistons , pins and circlips. If your e ngine .is a pre-unit , tell them you want .it balanced at 71%. If a unit e ngi ne, sp ecify 85%. QUESll0N: I purchased a Norton 400cc · Electra·. Can you give me the bore and stroke specifications for this model? What did the factory claim in performance figu res? D. C. :... P as co, Wash . ANSWER: T he 24 i nch or 400cc" Elec- tra" had a bore of 66mm or 2. 598· and a st roke of56m m or 2 . 20 5~ The Nort on was clai med to deliver 276 hp at 6800 rpm, wit h top speed of 90 mph. QUESTION: Sinc e I still have a twostroke motorcycle from the old school of mix it by hand rather tnen : Auto-Lube" what is the average fuel to oil ratio 1 shoul d use for general purpose running? G.P. Cleveland, Ohio . ANSWER: A mix of 1:24 or one third pint of oil per gall on of gas has been found a safe mix on all two stroke motors . Q UESTIO N: In recently gunking down my bike I flooded the mag wi th water and despite blowing out the unit with air and heating it wi th a tor ch there i s still water in the case. Short of takin g it off and having to retime my ignition i s there any way I can dry i t out? B. R.-Monterey Park, Calif. ANSWER: 1 s ure hope you have an armat ure le ft after hea ting the unit wi th a torc h! I s ugges t you re move one of the s park leads and pour so me Carbon Tet int o the magne to body . Carb on te trachloride evaporat es quickly lea vin g no res idue. Since water and Carb on Tet mix toget her, the evapora tion proce ss s hould tak e the wat er wi th .it. QUESTION: I am restoring a '250cc Aerial " Arrow" . How do I properl y take down the l ower end? R. V. - Huntsville, Va. ANSWER: I pre sume the top e nd , pri- mary c hain co ve r and chain has been removed . Nex t remove the c lutch a nd engine s proc kets , alternator and rotor. T here are two crankcase cove rs to remove. The drive s ide is secured by four nuts and one screw, one bolt. Th ere is an engine sprocke t key that s houl d also be removed. The right sid e cover is held by thre e s crews a nd three nuts. There is a lso a cranks haft rotor key that s hould be removed . T hi s e ngine ac commodate s a twopiece c ranks haft tha t must be split. Note that the right s ide .is hollow. 1nsid e the re is an .Alle n head bolt that mus t be removed by a lot of levera ge in a counter-cloc kwise direction . If yo u feel the bolt come loos e a nd the n ti ghten again and ke ep turning, for the bolt is al s o an e xtrac tor that will caus e the cra nk half to break free of .its taper joint with the left side half . Re move the right half of the cran kc ase by positioning the conne cting rod at the bottom and the n give a hearty outward pull. The left sid e may then be removed by positionin g the rod at top and exe rti ng the sa me outward pull. Both halv e s should now be fre e of the cra nkcase ce nter bearing. To remove that bearin g, heat the cran kcase and us e a drift to dri ve the bearing from its s eat. QUESTION: Is there any way I ca n check the rectifi er in my ignition circuit? P.O.-Granada Hill s, Calif. ANSWER: Dis conne ct a ll wiri ng from the rectifier termina ls and remove it from it s mountin g. Obtain a 6 volt battery (or twelve) and 6 (or twelve) volt .04 amp li ght bulb , dependent on ignition voltage • .Attach one wire from the .battery' s positive (+ ) terminal to the re cti fier mountin g post of bolt . Connect an oth er wire to the battery's negative terminal a nd' the other end to the li ght bulb. Now touch the bulb's metal body to ea ch of the rectifier's A.C. terminals , one at a time. If the bulb li ghts at a ny point the unit should be di scarded due to e xce ss ive " bac k flow ." Ne xt, connect the re ctifier's D.C. terminal to the batt eries negative post (-) and the wire and bulb again to ea ch of the .A.C. conne ctions . If the bulb lights, the re ctifier .is defective . Another check.is for continuity and an amp m ter.is need ed a long with a 30 e watt light bulb and 6 (or twelv e) volt bat tery. Conne ct the bulb a nd amp meter .in series with the bat tery ' s negative terminal and then to the rectifier A.C. terminals one at a time . The re ctifier's D.C. termtnal s hould be connec ted to the batte ry's positiv e pos t . In touc hi ng ea c'i of the A.C. terminals the bulb s hould li ght a nd ammeter read approxima te ly 4.5 amps a t 6 volts or 9 amps at 12 volts . Next , leave the wire s co nne cted as they ar e at the ba ttery pos t s and connect the ne gative lead to the re ctifi er s mountin g post or bolt. .Again put the bulb, me ter and positive lead in co ntac t with the rectifiers .A.C. terminals a nd look for a me ter readin g of 4. 5 amps (or 9 arnp .) , If it .is bel ow 3 a mps or 7 amps respective ly e. the rectifier must be changed . 100cc PRODUCTION CLASS WILLOW SPRINGS ROAD RACES WILLOW SPRINGS RACEWAY JUfY 1, 1968 st STAN SMITH BRIDGESTONE .: ON STOCK JOOn BRIDGESTONE JUST LIKE THE ONE YOU CAN GET AT YOUR NEAREST BRIDGESTONE DEALER 100 -, fOR THE NAME Of YOUR NEAREST DEAlER SO. CAL. McCUllOCH DIST. Inc. (2J3) 772-2J08 NO. CAL. COAST McCUllOCH (405) UN 3-5520 • • •