Cycle News - Archive Issues - 1970's

ASKE.C. ~ ( Got a techni cal problem that need s expert advi ce? Send querie s to " ,Isk E.C." c/o Cycle News . Your reply will appear in the _ paper within a fcw weeks. Hard questiuns may take a lillie longer to answer. By E.C. Birt Suzy Cafe I'm building a 250 Suzuki twin cafe racer with hopes of road racing next year. Cou ld you tell me where I can buy road racing cy linders, heads and pistons? If I can't buy an ything but sto ck cylinders, could you give m e th e nam e of a good road racing porter ? A Iso I nee d help in picking out th e best frame, shocks, wh eels. tir es and etc. . M. J. a 'Blen ess Albuquerque, N. Mex . I've looked allover and I can't co me up with any road racing cy linders you can buy. You will have to have the o nes on your bike built for you. I know of only two shops that have any ro ad racing ex perience: Suzuki City in California, phone (2 13 ) 674-1431 and E.C. & Walker in Florida, phone (305) 737-6917. If sent down to me I would have to have the complete engine and you will have to be ready to have yo ur bike tied up fo r awhile because I won't build it except one way. It wiII be dyno buil t which takes time but assures us both that the end res ult is what you need. Forframes , try Redline, phone (2 13) 886-1728. For shocks, you're going to have to have so me pre tt y short ones probably b uilt fo r yo u. On wh eels and tires I' d look at t he road racing art icles and see what the fast hays arc using. T hey can't be too wr ong. •. . Down range power I want to bring the power down in the range on th e '73 25 0 MX Yamaha at th e ex pe nse of a new enduro cy linder . I was plan ning on ma king th e ex haus t and th e intak e th e same as th e MX barrel; but what w ould be do ne to th e transfers and bo ost p orts ? .l1ayb e wi de n transfers or bo ost? Rais e transfers and lea ve bo ost ports st ock, or vice versa ? Increase stinger diam eter ? Thanks ' loads for y our help. D. McNeely South Gat e, Calif 34 First thi ng I'd do before I spent the bucks for a new cylinder would be to buy an enduro piston assembly. First oversize and bore the cylinder to .0025 clearance ; be cool about breaking it in so you won't stick it. T he enduro piston is a two ring piston (01' ke ring on the top) and straight rail on the bottom. This p ist on will im prove your low end a bunch. If yo u do get an end uro cylinder and raise your exhaus t port up the sa me as yo ur MX cyli nde r yo u're going to be in th e same boat that yo u're in now. Fro m top dead center t o wh er e the ex ha us t opens is t he most crit ical port in th e 'cylinder be cause t his is wh er e yo ur po wer stro ke is. I th ink I kno w what yo u want yo ur bi ke to do. You wa nt it just like m y own pers on al riders wan t their racers to be, p ull like a 501 Maico off the bottom an d run like a Yamah a road race r on th e top en d . Well, if fro gs had wings he wouldn ' t bump his butt when he j umpe d either. You can get close to having your pie wit h ice cream o n it . Try th e pist on tri p firs t. If y ou 're not hap py wi th that, ge t the enduro cylinder and raise the exhaust .0 25 and rais e th e transfers .050. This will give you what you want. and the rmal fu sion of th e impregnated fluo ro po lyrne rs. (T hat big word there is the special tr ick co mpo und. ) Don't co n fuse this pr o cess with the spray-on Tefl on (R) th at yo u have o n yo ur fry ing pan. 2) Do es it wor k? T ha t 's th e ne xt que sti o n that I have to ans wer and y o u will see all th e de tail s in o ur ne w co lum n callcd, "E. C. ~, Test Bench:" in a short time. I'm in the pr ocess uf havin g two of my Maicos and two of my 125 Tyrans treat ed no w in Flo rida wit h wh ich I wi ll be doi ng the testing. 3) If it 's steel an d it moves agai ns t any kind o f surfac e it can be tr eat ed. Sh ift ing bac kward B ein g ra ised or! [ apan csc and European machinery, I have grown quite accustomed to shifting gears on the left and braking on the right. When riding my B5 0 liSA .\IX I find it a very spine chilling experience to be under hard acceleration in third grear and stab the brake pedal or co me down a steep hill wi th a hairp in t urn at t he bottom. reach fo r th e brake, and hit neutral. Now, some p eople say give it time and I'll get USc to t he bike. but I lik e my reflex es just the way t hey are. 1I0 w can I switch sides of t he braking and gearing of this bik e ? Do es so meone manufacture a k it ? Can a sh op perform th e operatio n? What parts co uld I scra pe up t o do it myself? A lso , I would lik e to retain th e o ne d own and three up gear pattern. Michael Hopk ins FPO Sa n Francisco. Calif. Super Rat I wis h t o m od ify my 19 72 Hodak a Super Rat . What recomm e ndatio ns would y o u ma k e as to fuel oil mixt ure, po rting t ech niq ues, a larger carb , exhaust sys t ems. prop er j etting, bo ring out? Presently I ha ve a Web co head , com bined w ith a G.E.M. re ed valve. I have been t hink ing ab out th e k it th at yo u make for th e Barnt bik es. I wo uld appreciat e any help y ou ean gi ve m e on this matter. Mark Rusche Arlington Heigh ts, Ill. Mike, good thing that yo u 're in the Navy and have free medical care because it sounds li ke you 're guing to need it. Don't feet bad, I was born with two left feet also when it co mes to shif ting an English bike and I never co uld master doing things backwards. I called BSA and talked to the R and D Dep artment. They d on't have a kit and nev er made one. I co uldn' t co me up with an yone wh o has ever made a kit. But one th ing I do kn o w is th a t there is n o way to do it in sid e the engine. What I wo uld do is try and figure o u t a way to ma ke a lever type syst em with a rod th at goes under the bi ke and makes it sh if t o n the left side. It \\~II, not be a fun job bu t on e th at you should be a b le to handl e. If no t, back up three s te ps a nd punt. I) Fu el oil mixture; l 've used every oil there is at one time or the o t her, but I think th at I've finally come up with what I like the best. This is what I'm running in all m y Florida Pro team bikes at the moment : I1RL two stroke oil. mixed 3 2; 1 in m y 12 5 bi kes and 20 :1 in my 2 50 an d 450 Maicos, These are Pro bi kes an d we have watched them very closely during this series race and have had no se izure . no be aring loss, less wear than an y of th e other oils and no carbo n huild up. As far as horsepower, I haven't had a cha n ce to dyno that part but my mem ory tells me that it wasn't th e highest .out pu t when Dirt Bike te sted it. But that doesn 't mean to o much. There's horsepower in heat, for a sho r t time and I' m not interested in flash horsepower just as long as it makes t he com p lete mota with the same amount that I started out with, 2) Dig out your back issue of Cycle N ews, Feb. 19, 1974. I had an ar ticle on the Dirt Squirt that I think will answer most of your q uest io ns. Or if you wish you can se nd yo ur complete top end down to my Florida shop and we will be glad to look at it for you and advise you of what t o d o with it. I get th e feel ing t ha t it 's been wo r ked o n before3) If yo u 're loo king fo r ho rsepo wer you will need a reed pipe. Have yo ur dealer order an E.C. p ipe fo r yo u to fi t the type of ridi ng yo u do most. I ca n ' t list them all but there are 117 different pipes th at we build fo r Hodaka only. 4 ) The alloy top end like t he Bamt bikes and the serio us racers use costs $3 00 . What do you get for thai kind of mon ey? Well, a top end th at ha s taken me two ye ar s t o perfect. They're made in all sizes from 80cc to 140cc . T op end Jackpiner pipe kit I recently read your article. page 34, Cycle News East . July 24, 19 73. It was ab out "G o Fast m odif ications fo r t he Ja ckpiner." . I own a [ackpin er and am in te reste d in building an ex pansion cham ber f or it. Can y ou give m e th e dim ens ion specifications ? Can I use th e front half of myoid pip e? Thank you for your time and trouble. Louis Bondurant Atlanta, Georgia . No proble m. Th e near est dealer to you who carries E.C. prod ucts is Preci si on Cycle, 3403 Covington Drive, D e c atur, Georgia 3 0032. Phone 404/288-1220 . He either has it in stock or can order it for y ou . This is a kit th at lets yo u use the front part of y our Pen t on pipe. On e is availab le for all the Penton models 100 t h ro ugh 175 an d we're wor king on o ne fo r the 250, also . Cost is $24.95 wit h instructions so y o u can tun c yo ur pipe in three d ifferent st ages . A new side cover costs S 12.95 but you don't have to have it - it just makes yo ur bi ke look trick. 1 Goleta gas up: MX with Simi Valley Me By Ter ry Ash GOLETA , CA L., AU G . II Divisi on II' o f the 125 Experts rac ing today a t Golcta saw Mark Gambella, brother of Political Enduro ace Sharon Gambetta, (Bul) totally dominating the rest of the field. In the first mota it was Rob Ro llins (Bul) who grabbed the early lead, with Gambetta a close second. After almost co llidi ng in mid-air over th e triple jumps, the two d iced fo r a couple of laps before Gam b'et ta took over the lead for good , leaving Rollins and Ron Haase (Han) racing hard for second . When the checkered fe ll it was Gambetta fo llowed by Ro llin s and Haase . The second mo ta saw Rollins again get the early lea d , on ly to he passed by Gambetta after half a lap. This time Gambella wasn't fooling around, he went wild over th e triple jumps and was by far the fas test thru the hig sweeper. At the end it was Gambetta by 3 0 se conds, with Roll ins and Haase foll owing. Overall it was Gambetta with his grand sla m, with Roll ins in se cond and Haase in third. The Division II Expert 25 0 class was exciting as Danny Sanchez won both motos on his red tanked Penton. Sanchez got the hole shot in the first mota and held it till the end, winning by eight seconds over Danny Waller who had moved his Bultaco into second. Moto tw o w as N ate Sci . .. Sk icq . . . Scia cua's tum to take the early lead. It was really a thrill w a t ch i ng Seaqu . . . Squic . .. Squak .. . (oh the hell with it) hold off Sanchez's trick Pento n with his ratty old Yamaha. However Nate fell back to t hird, leaving Sanchez with th e win and Walle r in second. The Open Expert class was Von Pe terso n 's (CZ) . In the first mo t a he took th e lead on the first lap 'an d stayed in front, finishi ng 12 seconds in front of second place J im Co nn oll y (Bul ). In the second m o ta Pet er son had t o wo r k a little har d er , however st ill passed Mi ke Bea nway (B ul) an d Co nno lly for th e lea d. Entering t he last lap it was Petersun followed by Connolly. Two turns from the finis h Connolly 's Bultaco br o ke , but his wife and several onlookers helped h im push it across the line for third. Peterson took the Overall win with Robin Clark (!Ius) in second and Connolly pushing for third Overall. Results in the Results Se ction. Demolish ing a berm , Go leta sty le. Hey, is this Dirt Bike or something? ... Impreglon I un de rstand t here is a co m pa n y in FUllert o n, Calif orn ia that has a pr o cess calle d lmpreglon. It is claimed t hat th is process is unique in t hat T eflon (R) is im preg nated into th e m etal. No w th is outf it claims that a tr eat ed pisto n is much less lik el y t o seize and will last mu ch longer. My q uest io ns are: I) Do you have an y information o n this pro cess? 2) Docs it work? 3) If it does work . could various parts of suspension units be treat ed? Cary Bujan A nali cim, Calif Yes, I d o know so me t hing ab ou t it. I was con tac ted by this company a few wee ks ago an d t hey explained wha t th eir process is all abo ut . In short, Imp reglon is a process in which they penetrate right in to the metal. I) It is not a surface coating. Actua l penetration of the surface oc cu rs d uring the process. It produces a mechanical co mes compl ete with allo y cy lind er, por t in g, radial head. KaJ Gard, pist on assem bly. a nd choice of reed for stock carb or Bing , • :;; oJ oJ! Z Z w a

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