Kawasaki 2008
By TMX Archives on 13th Sep 07
IN no uncertain terms, Kawasaki has had a a couple of sensationally successful years since it broke with its joint partnership with Suzuki and forged out on its own to produce the all-new KX450F and KX250F models for 2006.
Grand Prix, AMA, National and Youth titlesfollowed in large numbers and already this season the list of wins byKawasaki machinery stretches to World and AMA Supercross titles, bothEast and West coast Lites Supercross crowns, the AMA Motocross Litestitle, the British Under 21 crown and numerous GP wins, while Kawasakiriders also currently lead the British MX series, AMCA 125championship, and the new MXY2 Youth class at the Maxxis series.
Clearly the fact that Kawaski Racing has employeda collection of incredibly talented riders to showcase its machineryplayed a major part in the success, but it should come as no surprisethat the machines themselves have won rave reviews the world over sincetheir release, regularly being at or near the top of magazineshoot-outs and proving hugely popular with the buying public too.
So will this trend continue for 2008?
Well, as you would expect with machines barely twoseasons old and which also saw some pretty major modifications in 2007,Kawasaki has not gone wild with the developments for 2008, focusingmore on minor mods and detail changes aimed at improving the all-roundhandling feel of the bikes specifically.
Launched alongside the long standing trustytwo-stroke KX125 and KX250 models on the new supercross style track atthe excellent Tonymoto MX Park, near Winchester, the end result is twomachines that stack-up pretty similarly to the two previous offerings,as T+MX News office jockey Ben Johnson and guest tester, 19-year-oldAMCA 125cc championship contestant Luke Spence, found out...
HAVING been invited to the official European launch of the KX250F andKX450F in Italy when they were launched two years ago and being very,very impressed with the machines initially, finding the 2007 versions asignificant improvement also, I was really interested to see how the2008 models fared against what had come before.
Pulling up at Tonymoto to be greeted with a coupleof display models standing proud, the first thing that struck me isjust how great the new bikes look.
In an effort to produce bikes closer to thefactory spec models, the Kawasaki designers have shod the 2008four-strokes with black alumite rims and designed the new graphicscheme to include black printed number plates for the KX250F and whiteversions for the KX450F, both teamed with a new factory style all blackseat cover. The result is undoubtedly the best looking pair of machinesthat Kawasaki has ever produced. Bold, solid and aggressive - they'restunning. Surely the KX250F is a contender for best looking bike on themarket in my opinion, although why doesn't it have that ace blacklooking coating that the KX450F forks come with?
Of course looks are important, but it is thechanges elsewhere that really matter, and in that area it is the KX450Fthat leads the way with improvements to the engine response and thebike's balance the main focal points.
To this end, the bike receives a new wedge shapecrankshaft which is claimed to reduce vibration and smoothens off thepower delivery whilst improving the bottom-end responsiveness. Theengine also benefits from a revised shift drum with lighter spring ratefor more positive gear shifting.
The rest of the changes are made to the chassiswith slight modifications made to the frame to improve the overall feelof the bike and low-speed cornering characteristics, while new enginemounts which hold the frame from a 10mm wider position are utilised topromote quicker cornering and increased rear-wheel traction.
Revised suspension settings front and rear havebeen made to also contribute to the bikes' front/ rear balance and helpthe bike turn quicker whilst improving the mid-stroke action, it isclaimed. A friction reducing Kashima coating is also added to the forksto further improve suspension action.
The KX250F shares the modifications to the enginemountings and the revision of the suspension settings to alter thefront/ rear balance also, whilst it features new crankcases withincreased rigidity around the crankshaft area which Kawasaki saysresults in a reduction of mechanical loss and thus more torque beingtransmitted to the rear wheel.
KX250F specific changes to the dampening of thefront suspension have also been made to improve the action in theinitial part of the stroke, whilst to keep in line with new FIM soundregulations, a newly designed 94dBA silencer is fitted, as it is on theKX450F also.
With no two-stroke development coming out of Japanat all at the present time, it is no surprise that Kawasaki's longstanding and still very popular KX125 and KX250 two-stroke modelsarrive in '08 with nothing more than a nice shiny new sticker kit. Itis a shame, especially given that Kawasaki's literature is quick topoint out that it still firmly believes in the two-stroke - obviouslynot enough to do any real development work on them though.
So, with all of the technical data run through, itwas out onto the newly built Tonymoto supercross track to try out thebikes and, true to form, all four machines performed pretty much as wehave come to expect of them over the past two years, which is no badthing in my book, and once again it is clear that Kawasaki has produceda seriously competitive range. It was no surprise that I continued myfine tradition of crashing either and a get-off meant that my day'stesting was cut short and I will have to leave the reporting back onthe KX125 in the very capable hands of young Luke Spence.
Two-strokes
KX125
LUKE: I'm a big lad at over six feet tall and Ireally noticed the effect this had on the KX125 as I really did justhave to keep it pinned everywhere to keep up my momentum.
This is usual for 125c two-strokes, but I don'tthink the KX125 has the strongest motor and it did struggle to pull mea bit a times. It's not a weak motor but it is very smooth and broadand not too fiery, and there are definatley stronger 125's out there.
For Youth riders and smaller guys though, it wouldbe perfect and the excellent handling is more than impressive. It'sreal light, razor sharp and so easy to throw around in the corners andinto berms and ruts that you can't help but have fun on this bike.
I'm not really the target rider for the KX125, butall in all I think it's a good, solid all round performer and a greatbike for Youth riders in particular.
KX250
BEN: IT'S easy to forget that it is just twoseasons ago that the KX250 was still capable of winning AMA supercrossand motocross national races, so it is no surprise that the bike isquite possibly the best 250 two-stroke on the market.
The engine is its big selling point, but really it doesn't have any weak points.
Refined is the word that springs to mind when Ithink of the motor. Along with Yamaha, Kawasaki continued its 250development longer than the rest of its Japanese rivals and I thinkthis really shows on the track with the bike
Right off the bottom-end it is very responsiveand, from there on out, the motor produces strong but very controlledand useable power right the way through the range and the torque andtraction it makes is very, very good for a two-stroke. In my mind it isthe most tractable, useable and rewarding engine in the class.
Perhaps the bike tails off at the very top-end abit quicker than some of its rivals, but to be honest, for me and themajority of riders, this is not something that you're really going toworry about too much, especially 15 minutes into a moto on a rough,choppy track.
As you would expect from a bike with the years ofdevelopment behind it the KX250 has, the chassis is excellent too. Wellbalanced, well sprung and handling superbly, the bike is razor sharp inturns in particular and it changes direction much more impressivelystill than the four-stroke models. The overall front to rear balance ofthe bike stands out as being better than the KX450F also and inparticular the front-end feels solid and planted at all times with thesuspension action >>> smoother and more progressive too.
All in all, the KX250 is a great two-stroke bike, I was very impressed.
LUKE: I do not have much experience of 250cc two-strokes at all, but like Ben I was very impressed with the KX250.
250's have a reputation as being too fiery, but Ididn't think the KX250 was like that and although it definitely has areally strong motor, what I really enjoyed about it was the smoothpower delivery. It was surprising how smooth it was and I found it aneasy bike to ride aggressively, which I was really impressed with,especially given that the track didn't offer much grip at all.
The chassis was great too and the easy handlingthrough the corners made it less effort to turn than the big 450 andless tiring. As you'd probably expect, the standard suspension isn'tperfect but it didn't seem to matter too much and the action was quiteplush through the bumps and over the jumps soaking up the heavylandings well.
Four-strokes
KX250F
Ben: So, the KX250F looks great and, after turning a good number of laps aboard this bike, it is clear that it rides great too.
It is easy to see why the bike is winning at alllevels for the AMCA and Youth ranks right up to the World and AMAchampionships. It is totally solid, a very impressive performer in allareas. Motor, handling, suspension, looks - it doesn't have a weak spotat all and as such it is a serious contender for the best bike in theclass. Really you don't need to say much more than that.
It is the engine that really shines through for methough, it's a very strong performer indeed. I've always felt that theKX250F was probably the most race orientated of the Japanese motors andmore on a par with KTM in terms of sheer grunt and torque, and thiscontinues to be very much the case for 2008.
Very revvy, the motor picks-up at the bottom endvery well indeed, and without the need to use the clutch to keep itfrom stalling, and from there it builds power quickly and verysmoothly, with a lot of torque through what is an exceptional mid-rangeto an impressive top-end performance. The motor does perhaps tail-offquicker than I would like, meaning you sometimes have to snick an extragear when you'd rather not but, all in all, the motor is very strongall the way through with no flat-spots or below par aspects that let itdown. Nor is it too strong and uncontrollable at any point either. Thebike's torque puts that power down to the ground very well too and, inthe mid-range in particular, the traction is superb and makes gettingthe power on out of corners a rewarding experience, and thefree-revving nature of the motor encourages you to be hard on thethrottle. It's very much an engine racers will like, and as you shouldexpect from the Japanese the gearbox shifts faultlessly too. However, Ifeel that fourth gear in particular would benefit from being justslightly longer to give riders an easier time with regards to thenumber of times they have to shift.
The excellent traction is also afforded by thechassis which is rock solid and is, to me, just a bit better with thosenew engine mounts.
The Renthal bars have a perfect bend for the bikeand were very comfortable from the off - which for me is surprising asI'm incredibly picky about that - and the whole positioning of theseat, bars, levers and pegs felt natural, and the whole bike just feelstotally planted and like nothing is really going to upset it, and thisis very much the case with you having to really get it wrong tounsettle the bike. It's getting up there with Honda now for stabilityand, teamed with the engine performance, it is a formidable package.
One area where it really shines for me is onsweeping corners where the back-end feels very stable indeed, butcornering in general is superb. My only grumble with the cornering isthat the Kawasaki seat foam is still too soft for my liking and youfeel as if you are sat in the seat on corners and not on it. Out of thecrate, the suspension was pretty good in my opinion, soaking-upnumerous big landings at Tonymoto without a glitch, but I did find theinitial part of the stroke on the front forks quite harsh still, whichis something I've found previously, but this is a minor grumble andsomething that, with the time to set-up the bike, I'm confident wouldbe remedied.
LUKE: I'm a 250F rider usually and although Ienjoyed riding the other models I felt most at home on the KX250F.However, I do feel that is the strongest model out of the range too.
The power produced by the motor is awesome, enoughto make me consider one for myself but, like Ben said, it is verycontrollable power and not too aggressive at all for any level ofrider, so you always felt in control of what the bike was doing whenyou cracked on the throttle hard in the berms and ruts, and not theother way around.
I was really impressed with the handling too. I'mover six foot but there was plenty of room in the cockpit to movearound without feeling cramped, and although I felt the back endsquatted down quite bit in the corners, I think the bike handled verywell indeed, and even the back-end sitting low didn't disrupt thefront. It seemed very light on track and easy to wrestle around in thecorners and over the jumps, and not too different from a 125 really. Itdefinitely was well balanced and changed direction really well, andalthough I'm no suspension expert - I've ridden bog standard stockstuff for four years - there was nothing that stood out to me as beingespecially hard or soft or too fast so, for the majority of riders, Ithink it would be fine right out of the crate.
All in all it's a really good 250F and the bike of the Kawasaki range for me.
KX450F
Ben: I've ridden the KX450F quite a lot over thepast two years, more so than any other 450 on the market and it's abike that I always felt could have been perhaps the best in the classbut for one small issue - I felt the back
end sat too low which made the front end too light and bit unpredictable, especially un-der power.
I was particularly keen to see how the bikeperformed in regard to this after reading the technical data andchanges for 2008 which allude to this being rectified, and to a degreeI feel that it has made the 2008 machine a noticeable improvement onthe 2007 model. You can't ask for much more than that really, can you?
I'm going to hold my hands up though and say thatI still think there is room for improvement on the balance of the bikeas I think the front end still gets light easily, but it is noticeablybetter, especially at speed. and the revised suspension settings,particularly on the front, make for a more supple, controllable ridetoo.
It is out of corners, particularly if you don'thave too much to turn against, where I think the bike sits low on theback and still unweights the front end a bit. This makes it push a bitand if you are not fully committed it can catch you out quite easilyand make the bike a bit of a handful when you tire.
I don't think this has been particularly helped bythe snappier bottom-end performance afforded by the new crankshaftsthough. It reminds me of the CRF450 from three or so years ago and itcan be just a bit fiery off the bottom end if you really crack open thethrottle in second and third gear out of corners. I prefer the slightlysmoother power delivery of the previous two years.
The power through the rest of the range is superbthough and very, very smooth. The mid-range torque in particular isexcellent and on the many jumps at Tonymoto that require just a quickblast of throttle to clear, the torque of the KX450F really shonethrough and made life very easy.
What also like about the KX450F is the gearbox.You do actually get four usable gears out of it, which is rare for a450, and for me it makes it a more rewarding bike to ride.
It's easier to find the right gear for maximumtraction and power and I actually find working the box more regularlymakes you concentrate more, stops you being so lazy and translates intoyou hustling the bike round the track faster than you would if you justsat in third the whole time.
I don't want to make out the KX450F is a poormachine, especially in the handling department, it isn't at all. Thebike is actually one of my favourites on the market.
It is just this one small area where it isn't asstrong as the rest of the machine, and as a complete package it is avery impressive motorcycle indeed and more than a match for its rivalsany day of the week. I'd quite happily shell out the money for one andride it all season long.
Luke: The 450 - I really enjoyed riding this bike.
As you'd expect there is loads of power on tap,especially off the bottom-end, which I thought was a bit too strongactually and made the front-end ride up and push a bit.
I think it feels quite a heavy bike, maybe becausethe centre of gravity feels low, but the power makes up for it asyou're hanging off the back coming out of corners - well me anyway.Unlike the Yamaha and Suzuki 450's, I thought the power was a bitsmoother through the mid-range and top end too, and the torque wasdefinitely better.
I also thought the handling was really goodconsidering it seemed quite beefy when I sat on it. I never really hadmuch complaint about suspension and it seemed very plush, the rear unitparticularly, which didn't seem to kick you in the ass going throughchoppy bumps or in the ruts.
All in all great bike!
SPECIFICATIONS 2008 KAWASAKI KX250F
ENGINE
Type: Liquid-cooled, single cylinder DOHC four-stroke
Displacement: 249cc
Bore x Stroke: 77.0 x 53.6mm
Compression Ratio: 13.5:1
Carburettor: Keihin FCR37
Ignition: Digital AC-CDI
Starter: Primary kick
Lubrication: Forced lubrication, semi-dry sump
Transmission: Five-speed
Primary Ratio: 20:67
Final Drive: 13:48
Clutch: Wet multi-disc, cable operation
CHASSIS
Frame: Perimeter, aluminium
SUSPENSION
Front: 47mm twin-chamber KYB telescopic fork with16-way compression and rebound dampening
Rear: Uni-Trak type KYB unit with 13-way compressiondampening and 17-way rebound dampening
Travel Front/ Rear: 315mm/ 310mm
BRAKES
Front: Single semi-floating 250mm petal disc with dual-piston
Rear: Single 240mm petal disc with single-piston
WHEELS
Front: 80/100-21''
Rear: 100/90-19''
DIMENSIONS
Steering Angle: 42 degrees
Length: 2,160mm
Width: 820mm
Height: 1,270mm
Wheelbase: 1469mm
Ground Clearance: 335mm
Seat Height: 955mm
Dry Weight: 92.5 kg
Fuel Capacity: 7.2 litres
SPECIFICATIONS 2008 KAWASAKI KX450F
ENGINE
Type: Liquid-cooled, single cylinder DOHC four-valve four-stroke
Displacement: 449cc
Bore x Stroke: 96.0 x 62.1mm
Compression Ration: 12.0:1
Carburettor: Keihin FCR40
Ignition: Digital AC-CDI
Starter: Primary kick
Lubrication: Forced lubrication, semi-dry sump
Transmission: Five-speed
Primary Ration: 22:60
Final Drive: 13:50
Clutch: Wet multi-disc, cable operation
CHASSIS
Frame: Perimeter, aluminium
SUSPENSION
Front: 48mm AOS-type KYB telescopic fork with 22-waycompression dampening and20-way rebound dampening
Rear: Uni-Trak type KYB unit with 22-way compressionand rebound dampening
Travel Front/ Rear: 315mm/ 315mm
BRAKES
Front: Single semi-floating 250mm petal disc with dual-piston
Rear: Single 240mm petal disc with single-piston
WHEELS
Front: 90/100-21''
Rear: 120/80-19''
DIMENSIONS
Steering Angle: 42 degrees
Length: 2185mm
Width: 820mm
Height: 1280mm
Wheelbase: 1485mm
Ground Clearance: 345mm
Seat Height: 965mm
Dry Weight: 99.8kg
Fuel Capacity: 7.2 litres
Specification: