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/125986
Front mounting springs on the expansion chamber w ere much better than the YZs . Here's the culprit . The shift adjustment screw came adrift and tangled w ith the pr imary gea rs. Three factors contrib ute to this; an increase in displacement of roughly )2% and a carb-reed valve package that helps the MX 400 reali ze its full potential. The en gine also co ntains a few pu zzles. The side cas es ar e cast with th e f ede rally required shift p attern and " kic kstar ter " label and also have a hole for a tachomet er drive. OUf suspicio n is that th e 360 engine is re ach ing the end of its developme n t an d that nex t year the 4 00 Enduro and :.IX line will share t he same eng ine in di ffer ent states o f t une . Adding to t h is su sp ici on are tw o sma ll brac kets at the bottom of the frame under the engi ne t h at could easily be ce n te r stan d ta bs . The CO l unit has also be en moved up under the sea t into a mor e protected area. It is no sec ret t ha t th e '76 Yamaha dirt b ikes will probably all be monoshock designs so what we have th is year as MX features will probabl y be standard enduro fa re nex t y ear. While at last year's ISDT we no ti c e d a c o u p l e of m onoshock Yamahas co mpe ting in the familiar re d and white European colo r scheme. If the above sp eculation does prove to be c o rrec t th en next year's enduro bikes ar e go i n g t o b e the hi gh performan ce off readers, provided too muc h isn ' t lost in the transition to street legality . There is a co nsumer tre nd tow ard a m u I t i-p u r pose bi ke for every th ing and Ya maha m ay just have the right machinery at th e rig ht time again for another DT·) st yle sales Colft-ng next week: Falta Czechs out the Austrian Grand Prix -... M 0.. < CB400 Super Sport: Inflation fighter of the sporting set success. confused with the 400 Enduro engine in an y way. The Enduro engin e is a further edi tion of th e well tried 360 while th e MX 400 engine appears to be a ma ting o f the 400 cy linder and radial head to a YZ 360 lower unit. The power is remarkable throughout th e rev range and. while we wouldn't call it an enduro engine. it does have more low end grunt than the YZ without losing any of the YZ 's instant power an d still retain a kick on th e top side of the RPM scale. Our te st, or rather impression. o f the bike was not without problems. The h andlin g upended several riders as previously mentioned, but th ese were riders un a c customed to riding a monoshock motorcycle. Rid ers of YZs loved it and co m me n ted particul arl y on th e ex t ra p ower and broad rang e. A rider of a GP works b ike stated flatly tha t he wished the engine was in his frame. We also lunch ed a sh ift adj ust ing scre w th at had co me lo ose and started to tan gle th e primary gears. The result was a few chi pped teeth on the main primary gear. A new screw was installed at Bill Kasson's , th e shi fting adjusted and the bike pe rformed without any further problems. Whether this was a fluke onl y t ime will tell . The screw is held in pla ce by one small lo ck washer and a nut. Attention to this when replacing gaskets or during occasional inspections would be a good ide a. If this (Continued on page 42 ) Pell- mell at Pell City ISDT Qualifier plus 3 .2 ton s of local cov.erage FOLLOW IN ROGER DeCOSTER'S BOOT STEPS rbo x is dual element type. Note COl place me nt change. Take a boot designed by a 3-time World Champion and manufactured to Torsten Hallman 's exacting spec ificat ions, and you have the Roger DeCoster boo t! Padded skin and ankle, steel sole support and steel toes make th is boot one you'll want to wear for maximum comfort and protection. Quick release positive buck les are just one of the many fe atures th at a wo rld champion demands. And it' s available with sure grip soles for enduro riders. 1975 Cata log $1.00 The works exposed. Major changes from the YZ include completely new airbox and swingarm. Snakey exhausu is mounted better than is YZ counterpart. Springs, nuts and bolts and rubber grommeu hold things together. , BAY AREA :'r~ ~~~ ~~tlt 13 5 2 Centinela , W.L.A , 213-826-7856 ,-~,,"61.. '-... ~/ CYCLE PARTS WATCH FOR OUR NEXT BIG SALE IN THI S PAPER - .. 25