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/126343
Trans-AmA Bike Test Suzuki works RO-420-78 an produ[tion Rm-400 n By Jim Gianatsis Photos by Chuck T~nnland and Glanatsis Part Two: Koji Masuda's Production Machine It may be somewhat precocious to call Koji Masuda's RM-400 N 'a production bike since it was probably assembled with just as much precision hand care as its RN-420· 78 works bike counterpart we looked at last issue , More accurately it is a pre-production test bike being used by Suzuki in the Trans-AlvlA Series to check for weaknesses and possibl e flaws in a design which is production oriented using m uch of the tooling , dies , and molds the eventual production bikes will probably use . Suzuki no longer does any of their production motocross bik e testing at the factory inJapan, but rather sends to America the pre-production bikes for testing and evaluation here by the U_S . Suzuki race team . Some three or four months after the pre-production models have arrived in th e States for testing and racing, and if no major design plans have to be ch anged, the ac tua l p ro du ction bikes can be expected to be availab le. This 20 means the RM -400 N will probably be availab le around the first of the year, while the RM·250 N , wh ich has yet to appear for testi ng in preproduction form , won 't be available until at least Feb ruary of 1979. Incase you were wondering along with me why the new RM's will be called "N" models instead of "0" mod els, to follow the logical progression of classification from the present C models , the a nswer from Suzuki has something to do with computer programing, and N is the next letter in the sequence of things that is available for use . So much for technology. Bu t technology and p rogress is what the R M-400 N is all about. And as im port ant as the original RM-250/ 370 A models wer~ to the sport of motocross when thev were first introduced back in the fall of 1975, so will the new R M-250/ 400 N models prove to be . We gave you a look at th e RN420 -78 works bike in part one of this impression , and in the words of Team Suzuki's Mark Blackwell, "The new production RM's will be as close to works bike quality and specification as possib le while keeping the bikes at an affordable price and allowing the owners to keep the bikes on a low maintenance schedule." To look at Koji's RM-400 N , other than the plastic tank to replace the much mo re expensive aluminum RN fuel tank, the production bike is indeed a direct copy of the works bike. The redesigned smaller engine cases with rearward positioned counrershaft sprocket, the 417cc cylinder fed by a 36mm Mikuni ca rbu retor , the frame design with it's long banana extruded aluminum swingarm , are nearly direct copies of the works bike. If it weren't for the fact the engine's main cases wer e di e-cast aluminum instead of sand-cast magnesium , you cou ld switch th e chassis and engine ' assembly on Rog er De-Coster and he wouldn't know the difference . And like the works bike, the production R M's are now back to la rge full -