MOTOCROSS MAYHEMWHICH IS EASTEST

AROUND THE TRACK?o Even though most Open-classers ignorelhe manufacfurers' intended purpose forthese machines, we cart't.If you read lastmonth's shootout between the the KX250and theYZ4004 you know that the 400 isatt unfatr advantage in the 250 class.Yamaha paid the AMA bigbucks to let the

' YZF into the 250 Nationals, but don'texpect to cher4r-pick at your local track(unless you give the promoter alargewadof cash). At most tracks, the 400 will haveto run in the Open class. So be it. Can the400 smoke the 380 KTM and the 500s?

To find out, we assembled Pit Pro'sRuss Wageman (former speedway andMX pro), Shane Trittler, Ron Lawsonand Lumpster to do laps on the fourOpen motocross bikes at Lemon GroveCycle Park (a hilly, fast track with SXobstacles). Conditions were primo. Eachbike was set up for each rider. Aftereachrider had ridden all four bikes, they(the bikes) were ranked , and the voteswere tallied. Here's how the chips fell:

I(awasaki I(XSOO. Power and com-fort were the KX500's two strongestpoints, and they go together pretty wellon outdoor tracks. The KX provedsmooth and extremely fast, and the frontend came up gracefuIly whenever wewicked it out of turns. The soft, wide seatheld the rider on the bike, and the lowbars kept us forward for cawing. The KXwould blubber because of a rich pilot jetand ping in the midran ge, hut it was asfriendly as it was fast. Power was neveran issue, and we could venfure into thedeep mud with confidence that the KXwould plow right through it. The KXcame out of corners well, but it was hardto force the bike into flrrns because of thegyro effect of the massive crank. Betweenthat and a tendency to follow ruts, it wasabttharder to go fast on the KX500 thanthe others. It also tended to wallowbecause of the super-soft suspension. Invoting, the KX tied the Honda for third.

Honda CRSOOR. Without a power-valve, the Honda 500 was the mostJuras-sic Open-class er,but it had the right kindof power for motocross. It hit hard in themidrange but signed off quicker than theKX. Our forearms also signed off quick-er on the CR, and Wageman complainedof blisters aftq riding it. Between thebmtal power delivery and vibration athigher revs, the CR demanded that therider pay a price for going fast. The CRwanted the revs chopped before it wouldlean for turns, just like the KX, but it hadstiffer rurprnrion and better turningmanners. The thinner, flatter, harder

seat also made it easier to slide aroundon the bike, so it was more fun to jumpthan the KX. Brakes were the best in thefield (surprise, surprise), but the CR hada clutch pull that would humble Popeye.Explosive power and a hard clutch pulljust don't mix, so all testers preferred the380 and 400 to either 500 for MX.

KTM 38OIUXC. Powennrise, the KTM380 ran much like the CR500, but therewas less power to deal with, so riderscould do more laps on the Katoom thanany other two-stroke. They also liked theMXC's faiily stiff suspension settings andthin, rigid feel. It was fun to jump andthrow into turns because of its lightercrank. Wageman complained of the frontend wanting to tuck in hrrns, and Trittlercomplained about too-stiff of a shock anda lack of straight-line traction. Clearly,KTM aimed the MXC at (ns) large4 olderriders. Lump complained about stalling,as the flywheel was a little too light andthe brakes too touchy for his tastes. Ev-eryone but Trittler ruted the 380 second(Shane ratedit fourth).

Yamaha YZ4OOF. Even though theYZF outweighed the two-strokes by 14 to17 pounds, it felt lighter on the track,

Surprisingly, the heayrest bike in thiscomparison is the most fun on a mo-tocross track, and it is, by far, the fast-est through turns. The YZF r.s the openbike that handles like a 250 and deliverspower as smoothly as a 125.

and all testers could go faster, longer onthe Yam aha. It made the least peak pow-er of the bunch, but what it did makewas so smooth that nobody complainedabout the engine. It also had the widestspread of power and rarc\y needed to beclutched out of turns. The Yamaha alsohooked up the best and could carry themost cornering speed. We could get onthe throttle much sooner in turns, with-out worry of looping out or slewing side-ways. It required less shifts per lap andless energy to hang on than the two-strokes, too. With the thinnest midsec-tion, the F was the most fun to jump. Itturned best and didn't do anything weirdor unexpected. Wagem anhadn't ridd ett abike in a yea\ and he instantly went faston the YZF. We had a hard time gettrnghim off of it. It pegged his fun meter, soWageman ordered one immediately afterthe test. The YZF had another convertfor its four-stroke crusade. o

APRIL 1998 / DIRT BIKE 31

NEwSPEcIEq *j!!#,#Ifi,-,IN ILIRA S S IC #H";"?:ir,:if 'Jitt't f :1":;!,x?::'n'

" T:ffr:teaniis more predictabte than

DOIN'THE DUNESTEAM SMP'S

INFLIGHT FAVES

o To ahardcore se$ment of the off-road'

c1an, Open-class bikes should come

stock with paddle tires instead of knob-

bies. Duners and hillclimbers love the

adrenaline rush of aimin$ the front fen-

der at an insanely steep rarnp, pullingthe open-class ttt$$et and upshifting'Guys 1it<e Robbie Knievel, Paul Pinson-nault and video sensation Mike Cinq-

32 DIRT BIKE / APRIL 1998

mars live to $o big on dirt bikes' So we

enlisted the help of Team SMP for the

duning section of the shootout' Mike,

Shawn Highland, Dou$ DeHaan and

Tommy Clowers aired out the contend-

ers at the ImPerial Sand Dunes (ak'a

Glamis). We aie talkin$ pinned in fifthd.une d.oubles. Here are their thoughts

on the four oPen-classers:Kawasaki-KXsoo. If theY had to de-

scribe the KX500 in one word, thatword, would be "couch." The KX was

wid,e, soft and more plush than aBarca'lounger. It was comfortable and stable

Oddty, Team SMP liked the heaviestbike-in the comparison for its 21o-likehandling and iumPing Prowess' TheYamahi YZ4OOF has the least crankinertia and the thinnest pilot compart-ment, so lT iumPs most like a 25O andgets the SMP squeal of aPProval'

runnin grrdges and cawtn$bowls, but itwas a pig on jumPs. Clowers com-

plained ibout the massive flywheel ef-

fectwhen jumpin $, and' the whole crew

felt the sutptttsion was soft' Nobody

complained about power' thou$h' TheKX pnt out the most boost but burbledat low rpm and. Pin$ed under a load(raising ih. ttt.dle helped, but it n-eeded

iu.r g;). Vibration was noticeable butnot alnoying. Havin$ the widest mid-section, tLe KX wasn't an SMP favoritefor jumps.

fiotdt CRSOOR. SMP liked the

NEWSPECIESIN JTJRASSICK

CR500's monstrous hit and top-endpower, and they felt it tan cleanq thanthe Kawasaki. They also preferced thestiffer Honda suspension to that of theKX500, but thought the Honda forkwas still soft for their needs. The abilityto move around on the bike is super-im-portant when you are tapped in fifth,and the SMP guys liked the CR's thin-tter) flatter midsection. Some rated theHonda third-best for dunes, while somevoted it second. It pinged some, but notlike the KX and KTM.

KTM 38OMXC. Nobody complainedabout a lack of power, as the smaller Ka-

34 DIRT BIKE / APRIL 1998

For running ridges and bowl ballet,the KXS@ is the king of the dunes,but its couch-like pilot compartmentand super-soft suspension turned offthe SMP freeriders. They complainedof heavy landings and a lack of whip-ability.

toom ran much like the CR500: cleanand hard-hitting. Some believed it hitharder and lower than the 500s. Every-one complained about vibration, how-ever. The hands went first, but therock-hard seat took its toll, too. The stiffsuspension was well-received by theleapers , and they liked the light feel inthe atr. The comparatively light fly-wheel gave it inflight manners like a

250, so SMP was impressed with theAustrian machine.

Yamaha YZ4OO:F. We honestlythought the new super thumper wouldlose in the dunes. Ever since its intro-

SMP's freestylers whipped the KTM38O hardest and launched it the far-thest of all the two-strokes. Iheseguys usually fly tweaked 250s, so theyfelt right at home airing out the MXC.M ike Cinqma rs demonstrates.

duction, w€ have looked for conditionsthat would put the YZ400F at a disad-vantage. The dunes were our last two-stroke hope. Team SMP voted theYamaha tops because it did the best250cc two-stroke impersonation. Han-dling was light and crisp, like a paddle-tired 250 (*. simply let the air out ofthe new K695). It even whipped like a

250 in the air. SMP liked the F's mid-section and ergonomics best, and themidrange torqu e made up for the com-parative lack of top-end. It outjumpedthe two-strokes and was fought overlike the only girl on a desert island.o

NEWSPECIESIN JL]RASSICK

OFF.ROAD RATINGSHOW THEY COMPARE

ON THE TRAIL

o Kawasaki and Honda are sti1l making500s because people are still buying500s-but not for any motocross track.Most Open-classers dig the versatility ofthe big bikes over everything else. Bigbikes work as well on trails and in thedesert as they do on a real MX track. Atthe top of marry of our gnarlier testhills, only Open-class tire tracks are vis-ible. With the addition of a big tank,500s become the ultimate all-aroundmachine. Here's how the mixed tratl

Pertect carburetion, instant thtottle rc-sponse and claw-hammer reliability high-light the Honda S(X)'s engine. lt can alsobe bored. Off-roaderc have the option ofadding flywheel mass, sfeel clutch platesand a wide-ratio tranny to smooth thebeasf for trails.

Stock, the KXS@ burbles and pings onits way to a 62-horsepower top-endrush. Team Green leans the pilot (55 vs.58) and needle (one clip) and richens themain (170 vs. lffi) for off-road use (withrace gas and oil @ 4O:1). The KXSOO alsoneeds more flywheel for trails.

NEWSPECIESIN JIJRASSICK

The Yamaha YZMF is pertecily jettedand doesn't demand attention withmoderate altitude changles. It's geareda little tall for tight trail, and the clutchpull makes the two-strokes' clutchesfeel light. On the other hand, it doesn,tstall at low revs like a two-stroke.

nuts at Dirt Bilee rate the four con-tenders:

Honda CRSOOR. 'Backing off of allfour compression clickers gave the Hon-da 500 decent tratl manners, but it wasoutshined by the Kawasaki for desertand woods use. The CR's explosive mid-range made it a handful in tighter sec-tions, and its twitchiness at speedelevated the desert pucker factor. Witha massive flywheel weight (and steelclutch plates), valving and a steeringdamper, the CR carT be made to run

l Ot alt theopen bikes,the KTM38OMXC is themost finickywith changesin altitude.Tranny ratiosare identicalto the 38OSXbut final gear-ing is lower(14152 vs.14/50), andthe MXC hasa lighting coiland flywheelweight tosmooth poweron tight trails,

with KX500s, but it still isn't as easy orcomfortable to ride off-road as the KXor KTM.

Kawasaki KXSOO. For masters ofthe casual pace, the KX500 is the mostcomfortable choice. The wide, pillow-soft seat and feather-bed suspensionisolate the pilot from the terratrt he isstrafing. A big tank makes the midsec-tion wider still, so it gets harder to moveforward for turns. Stone stock, theKX500 is the ultimate desert machine,and simple mods make it capable ofwinning arry desert race. However, intratl testing, the Kawasaki fell behindthe KTM and even the YZF. Far behind.It was simply too wide and cumbersomeon tighter trails.

YamahaYZ4OOF. Since the Yamaha\ /R400F didn't arcive in time for thiscomparison, we enlisted the YZ400F asthe four-stroke alternative to the bigtwo-strokers, and it performed surpris-ingly well. It gobbled high-speed sandwhoops well and showed the stability atspeed of the KX500. In the woods, theYZF proved extremely sure-footed onsingletrack, and it leaped logs easily.The suspension wasn't as plush as theKX's, but it got the job done. Only on€oat trails did the YZF's motocross her-itage become unwanted. First gear wastoo high, so clutch slippage was mas-sive. Again, the V/R400F would be bet-ter in high-speed sand and whoops.

KTM 38OMXC. Wirh its pseudo-wide-ratio transmission and enduro fly-wheel, the KTM 3BOMXC was the kingof tight tratl., and it had enough grunt toscore well in desert settings, too. TheMXC also had more gas range than theothers, yet it was almost as thin as theYamaha. We liked the suspension actionbest in the desert, but it was compliantenough to be comfortable on roots androcks. However, the 380 was the easiestbike to stall on the trail. It barely edgedout the fuIl-moto YamahaYZfor trail use,but the \ /RF sets the new high-watermark for off-road Open-classers. tr

APRIL 1998 / DIRT BIKE 41