KLX450R v KLX300

[The MekonMember]

Arrived home the other day and have now taken delivery of the KLX450. Wasted no time in getting it dirty and headed for my regular ride spot.
This is a very different bike to the KLX250/300. The throttle response is instant and this takes some getting used to after the softer power delivery of the 300. I think though that I was wringing the neck of the little bike most times I got on. Now I find I am often opening the throttle and finding that the bike is not yet pointing in the direction I want!
There is also much more vibration than on the KLX250/300. I am a bit disappointed that this is so, as I like smooth bikes. Maybe the smaller bike is just too smooth.
The suspension is much firmer on the 450, and I am only using about ¾ of the stroke as opposed to the lot on the 300.
The weights appear similar – certainly the 450 does not appear to be any lighter than the other bike.
Mine was delivered derestricted – throttle stop removed, baffle out. It makes a nice growl.

At present I must say I am a bit intimidated by this bike and if given the choice would ride my old bike. It may take some time before the positions are reversed

More later as I have only done 50km so far.

[The MekonMember]

Have had the bike a week now and been on 5 rides. Already damaged the exhaust header in a fall – very vulnerable where it is. Also ran into a bank and cracked the front fender! So much damage in so little time. I have stacked my 300 more times than I can remember and some big ones too with less damage than this thing.
Had one problem apparently common to many. Clutch slipped in higher gears. Some bikes delivered with two washers behind the clutch basket. Fix is easy – remove one washer. Still no Kawasaki bulletin about this, and the dealer says he has had 5 or 6 with this problem.

[Anonymous]

I reckon it will take a while to adjust. For the bush trails and tight stuff though the 300 is a nifty little weapon.

I ride a 450 because I’m insecure and need to feel like a man. I’m positive I could ride a 300 2 smoker quicker though.

The best thing is to do what you have done and have 2 bikes! Albeit two 4 strokes

[Paul SouthwellMember]

I ride a 450 because I’m insecure and need to feel like a man. I’m positive I could ride a 300 2 smoker quicker though.

I ride a 610 because im a big fat bastard:( :blink: :laugh:

[Anonymous]

You were excluded from my generalisations Tiny :laugh:

[aaron childsMember]

Hey meckon
Just new and saw ur topic on recieving your bike de restricted . got a few q’s im new at all mechanics (though know the basics) and aint no (near enough is close enough guy) but when i got my bike from dealer it was a pussy excuse for a 450 so i ripped out the snorkel, bafell (though now im taking apart the throttle to see whats the go)
after my first service I expressed my dissapointment at the throttle responce and recieved a different bike in return ( well seemed to be the mech. said he played with the carb,
Then before the next service i flipped it in 5th and shredded my ass so the bike wasnt looking the best , when i got it back it seemed not as savage….. im up for a few races soon and want the most out of this green machine any pointers???????? though i raced years ago all my mechanics were taken care by sponser and now starting my 5 kids into mx i have alot to learn!!!! any help would be appreciated:S

[The MekonMember]

Hello Aarochild,

It seems like you have done what is required to derestrict the bike. Mine still has the snorkel in. The important parts to remove are the throttle stop screw and the baffle.

My bike had a clutch problem. A lot of the KLX450’s are being delivered with two thrust washers behind the clutch. Should be only one. Clutch will slip otherwise. Still no bulletin on this from Kawasaki.

Sounds like you have a bit of a background riding dirt bikes. If you came off a CR500 or KX500 this thing may be a bit of a pussy! To me coming off the 300 it is a beast. That said it does not have as much go as my mates 05 YZ450 which is a pure MX bike and would have 50+ hp to the KLX’s around 40 hp.
You can make these bikes up to the MX level of 50hp but you will not get the same reliability

[Mick DMember]

The Mekon wrote:

Quote:

Have had the bike a week now and been on 5 rides. Already damaged the exhaust header in a fall – very vulnerable where it is. Also ran into a bank and cracked the front fender! So much damage in so little time. I have stacked my 300 more times than I can remember and some big ones too with less damage than this thing.
Had one problem apparently common to many. Clutch slipped in higher gears. Some bikes delivered with two washers behind the clutch basket. Fix is easy – remove one washer. Still no Kawasaki bulletin about this, and the dealer says he has had 5 or 6 with this problem.

I saw one the other day at the pony express and was surprised at how vulnerable the extravigant pipe configeration was.

[ChrisMember]

Mekon, I’ve seen dyno charts that puts the KLX250 at about 26HP that’s with Pipe, jetting and 300kit, any ideas what the 450 puts out stock.

Cheers
Chris.

[Anonymous]

Chris, form the look of his post above is would seem about 40hp. This seems down on most other 450’s though which I believe are generally over 50hp.

[Anonymous]

Mekon – Are the figures/estimations quoted flywheel or wheel based HP?

[The MekonMember]

It is my belief (from reading US magazines) that the current crop of 450 enduro bikes only put out in the region of 40hp when on a proper rear wheel dyno. (not the drum type which are a joke) This means all of them. The worst may be around 38hp and the best around 42hp. The equivalent MX bikes top out around the 50hp mark – I think the KLX was 50hp with the new KTM 51hp. These MX bikes are much more prpwerful than their enduro cousins, though the enduro bikes can be modified to approach the MX bike HP.
No one should delude themselves about true rear wheel HP. My much modified 300 would be lucky to have 25hp.
Some years ago I had a modified E type Jaguar that only pulled 168hp at the rear wheels. The dyno operator said that the V12s (rated at 300hp) only made about the same, and that only race cars showed more than 200hp.

[aaron childsMember]

The ass shot im posting was a result of 5th gear flip ,over crest of a hill , had a mate next to me and herd the hulk valve bouncing as it flipped end over end 95km! i agree the pipes are very vunrable though after checking mine out all i had to do was replace my number plate!!! lol (though i wouldnt recomend this as a test!!) ouch!!

[Mark TimmermansMember]

I have a klx 450, traded in my klx 250 on it, I was a bit intimidated with it at first, had it derestricted at the first service now it flies. I am 105kg pulls me up any hill easy. No problems with this bike it flies heaps of power, the more you twist the throttle it just keeps going harder

[Anonymous]

The Mekon wrote:

Quote:

It is my belief (from reading US magazines) that the current crop of 450 enduro bikes only put out in the region of 40hp when on a proper rear wheel dyno. (not the drum type which are a joke) This means all of them. The worst may be around 38hp and the best around 42hp. The equivalent MX bikes top out around the 50hp mark – I think the KLX was 50hp with the new KTM 51hp. These MX bikes are much more prpwerful than their enduro cousins, though the enduro bikes can be modified to approach the MX bike HP.
No one should delude themselves about true rear wheel HP. My much modified 300 would be lucky to have 25hp.
Some years ago I had a modified E type Jaguar that only pulled 168hp at the rear wheels. The dyno operator said that the V12s (rated at 300hp) only made about the same, and that only race cars showed more than 200hp.

I agree, rolling drum type dyno’s are not accurate. However, they can be used for comparison. Bike against bike will still a percentage deviation in terms of power and torque.

MX bikes are made for more explosive power as they only run for shorter periods of time. Enduro bikes have to be far more reliable and therefore are effectively ‘detuned’. Normally a set of cams will make an enduro bike much more lively.

Going back to the drum dyno. They measure power in terms of effort and then people use some value for transmissions losses to determine what the flywheel HP is. Flywheel hp is what most manufacturers quote (although not many bike manufacturers do) as they test the engines on a test bed. It also sounds much better in the sell.

Rear wheel HP is a true picture of what your beast can do. I had a Toyota Supra with 343 rear wheel horse power. Equivalent fly wheel horsepower would be high 400’s.

The V12 Jag wouldn’t give very high horsepower figures as they were designed for cruising not racing. It would pull a train along all day but horsepower is more function of top speed than acceleration. That and the fact that they were shit :p

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