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/126436
KESTBA KES TBJlE . ~. , , - - - - - - - - - - - - - - - - -.......----.....1$ Husqvarna 390 CR The most competitive production bike in the Trans-USA Series WaS Chuck Sun's nearly box-stock 1980 production Husqvarna 390 CR. The bike is very similar to the 1979 model with the exception of minor changes to the rear frame section which reduces weight slightly and allows the use of a smaller rear fender and flatter saddle. The bike becomes a lillie more comfortable to ride and a lot better looking in the process. In the handling department the new bikes also come with slightly longer swingarms to keep the front end down on the ground. Mechanic Eric Crippa modifies the new swingarm to make it an additional l-2 inch longer for Chuck, and together with the excellent stock Ohlins shocks the bike has 310mm of rear wheel travel. The front suspension is stock Husky with 290mm air/spring forks and triple clamps from Pro-Fab to stiffen things up slightly. Eric also likes to add his own porting touches to the 390cc engine which is otherwise stock and unchanged for 1980. The transmission remains a 6· speed sitting below a reed valve inducted cylinder fed by a 38mm Mikuni. Some of the Husky Support Team riders like Ron Sun are using the new Mossburger reed valve assembly and reporting excellent results with an inCrease in power and tractability to the already excellent 390cc powerplanl. ~ ~ ..... '"' Q) ,.c e Q) :> o Z Above: Chuck "Rising'~ Sun with mechanic &ic Crippa and the hottest stocker in the series. Husky's 390 CR. Below: "Daddy Long Legs" Mike Bell with wrencher Dave Osterman and the possibly 465cc Yammer. Yamaha OW-41 Yamaha's works open class monoshocker remains unchanged since its introduction at the beginning of the 500cc Nationals earlier this year. The bikes being used by the American team riders also happen to be a year behind what Heilli Mikkola raced in the World Championships. but it doesn't matter much since the present OW -41 is already one of the best works bikes around. Kayaba leading axle air/spring forks offer 290mm of travel up front matched by a Yamaha coil-over deCarbon monocross unit at the rear with equal travel. Yamaha's works bikes are also the lightest and the OW-41 tips the scales at 218 pounds with heavy-duty tires and no titanium whatsoever. The works OW-41 engine has magnesium cases and a 5-speed transmission. l'he cylinder is aluminum with chrome bore, conventional 7porting without any trick RPM compensating exhaust valves, and has reed induction with a 38mT(l Mikuni carb bolted on behind. Exact engine displacement has not been disclosed, but is believed to be 465cc. • 19