Cycle News - Archive Issues - 1960's

sen and KenyOll In tow. Hansen' got by DUfeobaugh In lap 2 as I:UfeDllaugh began to look as loose. Hansen then began to pull away unUJ lap 3 when DUfeobaugh got wiele In tile first turn and Kenyon got by with no problem. Kenyon closed It uP unUJ the yellow flag lap where he was right on him, just waiting tor Hansen to make a mistake. In the short bank Hansen did make a mistake. Down went the bike and as the rear wheel went wide Kenyon bad no place to go but down and ott went Dlftenbaugh to the win. Tom Madlem returned to the 375 NovIce class with a C Z and had no problem winning his class. Stan cattott, led ott the 200 Novice main with Ivan Shigemasa In second and It looked as lf they might run oft and hide, but Gary Kunsman all of a sudden appeared In lap 2 to take over. Shigemasa barrel shot Calfolt exiting the tlrst turn and passed him Over the jump and tlnlshed second. (Results on page 20) Gaeele of "elltwelcllls drop 1IIe h3ll)mer as 56x Charlie 5ule finds a little more tradlon 1IIan he desired. - PaI0 All 0 ACI Ion Scott Dlff..baucll cuts It real close to 1IIe turn on his w~y to 375ee Expert elan win. TECHNICALITIES Peaky Power Versus A Flat Torque Curve , , By Tovicda ,Two of our local high speed trial riders purchased Hodakas recently, and like all would-be Tommy Turners, tore the bikes down and started making the rounds to gather all of the speed secrets that they could, One bullt his bike tor maximum horsepower, paying no attention at all to the r .p.m. range where all his add.ed power would hit him In the taU. The other one being (a) smarter (b) more cautious (c) lacking of guts (check one), built his bike towards a more realistic horsepower output and consequently a much wider power band (although not as much ot It), It will still go oft and hide trom a stocker. The would-be hot shoe went tor a 13to-1 compression ratio, seven ported the barrel, raised the exhaust port 1/16 of an Inch and ran the tlnger ports a bit higher than the stock port location. He then removed the fiywheel and added a total loss battery Ignition, advanced 12 degrees beyond stock to fire a surface gap plug ala Kawasaki. Getting into the carburetion department, he threw everything away and started over with a set ot Gemco reeds, Tillotson pumper carb and a to-inch ram tube with the air cleaner tucked under the seat like the big boys. Running a reed valve allows you to do weird things to the back of your piston, and our boy did them. He bought one Dykes piston, one hack saw, and twotUes and did his best to cut a tour-Inch hole In the back of a two-In.ch piston. The machtne was topped oft with one ot Tom Turners' mucho hi-rev pipes and it goes like blazes. Plug reading tell wblch jets to us. Proper Jetting Is critical to keep a 2-stroke tunnlng good. Too lean will burn the piston, too rich saps the power. Now a brlet rundown on the tamer ot the two bikes and then we'll take the little bombs out to the desert. We'll try them against some hills, and do everything but tlattrack with them. The tamer bike Is running stock port location, with the ports highly polished. It's been five ported (tor cooling), raised to 11.5-t0-1 compression ratio with a Dykes piston and blasts out of a Turner Torque Pipe. The Ignition and carburetor have been lett stock. The bike Is easy to tune and at the time we took them out to ride, both bikes were running real strong. It you wonder why we are comparing a tull-race Hndaka against a warm semlstocker, you may be in tor a surprise. With equal riders, both weightng 200 pounds, the bikes were so close In most events that it makes you wonder why hot shoe spent all his bread it Isn't going tor a low number. In a dirt drag race, the mUd one would hole shoot the peaky bike everytime and hold him oft III 3rd gear, then the hot one would come to lite and go around like gangbusters (If the trall were long enough). It there was no room to pass, hot shoe would sit back there eating dirt and cussing. Hill climbing on any 100Cc Is an art in itself, and trying to climb with a ~ tI) .. ~ lo::I oJ U G - Who wouldn't be a racer, wl1ll a pit erew like 111 Is? bike that's peaky and has no power below five grand really Is a pain. When you slog it down to six grand in second cog, you have maybe 4 hp so It's getting steep and you bave to pick uP first cog, right, so you stab the lever, grab tlrst gear and try to teather the clutch between 0 and 17 hp on the side of a mountain. Sometimes you can make It, but most of the time you pull a 360 degree wheelie and loop out. On the tamer bike, we wouldn't even have to downshift till the engine revs about tlve grand, and we would still have about 6 hp left. Going into tlrst, we pick uP to approximately 11 hp and the bike would stay In the track and make the top tlve times as often as the peaky one would. On the Saddieback motocross course, the starting line Is almost a straightaway for 100Cc machtnes and with that In mind, tha peaky one would always pull maybe tive bike lengths on the torquer. But as soon as you head into the bends, the torquer would be right uP there dicing, and several times copped the lead, at least until the short straight. Bear In mind that we changed riders back and forth to compare the bikes' ablllty, and not our high speed trail riders. We didn't take them on a tlattrack because the hot one would always be In 1ts power band and would hide from the torquer, same tor the rast courses. ~ ~ · I J Across the desert It's not so much horsepower, but who bas the most hair. The Hndaka, with its stock suspension, just won't take a flogging with 200 pounds ot lard trying to stand up and go, so it It were smooth enough, the hot one could get away. But that smooth stretchAlways leads to a hill where the torquer would pass hot shoe sliding down the hill on his side alter a glant loop. Just touching lightly on the subject of reliability, since this article was begun, hot shoe has blown two pistons and is making noises that sould like, HI beat all you guys, so I think I'll delune and give you guYs a break." It you are an out and out racer, this article won't do a thing tor you. But It you are like 95% ot the Hndaka owners and just want to play in the dirt a little bit, try to keep your hop- up in line wi th the type of riding you will be doing and don't lose the reliability the tactory built In for you. And it you do go tor a bunch ot modifications, try to stay away trom a road racing tuned engine, unless you're a road racer. TURNER Expansion Chmlbers Port, Polish, Five .. Seven portlne lor (213) most 2-strokes 519-7717 Also Reed Portlne HolI's 10-' 6025 Maywood #11 Closed Wed. & Sun. HlIlIlinelon Park, Calli. ~~~~~ --~~~~ ~--F;i;;;iScOUNTCOU-PON-·BO;H-' (present at :: bOI office) i@l .-:1 DAYS: ~}@I NS4 .00 I~ ews-~ : : Car I s b a d / Cyc I e .!el ~ Motorcycle Circus I~I ~.; · ~ By W,H. Spencer FREMONT, CA" June 1 - Palo Alto M.C.'s second scrambles ot the year at Fremont Raceways played to a thousand spectators and nearly 300 riders. The track was rough and the racing tast. Lance Anderson won the maln event, on a Triumph borrowed trom Gene Connant, over lOw, Rick Otto on another Triumph. Both otto and Anderson pulled away trom the pack and bad their own race. One of the best shows of the day was the 650 Amateur maln in which Steve Spence worked his way trom the back of the pack to a tlrm third place tlnish on a track that is very hard to pass on. Paul Karpinski won his main and promptly tell ott with much enthusiasm as Craig Goodwin went ott the track with mechanical ills alter baving passed the first lap leaders; The 375 Expert maln brought out District 36 #2 racer Al Kenyon to ride against Dave Hansen, Scott Diftenbaugh and five other riders. After Kenyon's double win at Uvas Dam and a win iii the 250 Expert here, It appeared that he was going to do It again. A t the drop of the flag, Dlftenbaugh took the lead with Han- ! ~ i '0. . .., " U e 4 to 12 years old: June 14 & 15 , 1969 C~lldren Admission prices: Saturday S2.50 Overnight campine: FREE $1 both days (no discount) ~ • S2.00) With Coupon: ... Sunday S3.50 With This Coupon S3.00 This u . WITH THIS COUPON 0 ''m . I@I I~ .... 1 ~@li . _ - - - - - - - . _ • • • • - - . __ . - • • _~ ! -

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