KFX450?? the truth about um...

[zjmr51]

EVERY ONE PLEASE TELL ME THE TRUTH ABOUT THESE KFX450....
i currently have a 04 YFZ450 i bought new and it has everything done to it set up for GNCC racing and i love it.
I ran across a good deal on a new 08 KFX450 bone stock and bought it thinking i may switch to KAWI... i have realized its gonna take atleast a grand to buy pipe,programer,intake on this thing to get it to run with the other brands... BUT I WANT TO KNOW HOW THEY ARE HOLDING UP AFTER BEING RODE!!!

ANYONE HAVING ANY PROBLEMS OUT OF THESE NEW BIKES?? ANYTHING BREAKING, MOTOR, FRAME, any common problems,ECT.....

shoot me straight and give me some feed back... you wont hurt my feelings either way.....

--i not heard much about them and wondering how the aluminum frame is holding up.... anything cracking or striping out.

--hows the E.F.I doing? any problems with the motors or wireharness like the KFX400 had WAY TOO MANY TIMES.

--drivetrain holding up? since this does have reverse...

ANY INFO U GUYS CAN GIVE ME ON HOW THESE ARE HOLDING UP OR ANY PROBLEMS PEOPLE ARE HAVING WOULD BE GREAT TO KNOW..... before i decide to keep and dump a lot of money into it getting it set up for GNCC.

THANKS to all exrider members.....

:eek2:

[k4f5x0r]

ill try to keep this short and to the point. if you have any questions about any of it just ask and ill go into further detail.

Frame: i have not heard about any frames breaking under any NORMAL circumstances. I have heard of one rare instance where the guy claims to have flipped going 10mph and cracked the front square area where the steering stem mounts.

Engine:although they have had some trouble keeping these together under extreme race motors( factory kawasaki, cody gibson etc) as long as they arent put under any crazy stress they are pretty good. In a few rare instances(on bone stock motors) the connecting rod has broke causing the motor to tear itself apart. I have heard once you put too high a compression piston on the stock rod that it greatly increases the chance of it to break. no info to back this up just a mixture of an assumption and some forum info.

EFI:I'll be honest here, it doesn't have all of the kinks worked out like the LTR. for some reason alot of guys on kawi's have to turn the killswitch off to kill the motor, and while leaving it in the off position turn the key to off. On some KFX's the battery's would have a slow drain if you just turned it off using the key for some strange reason.
I know a guy over on kfx450hq.com strips wiring harness's down to the bear minimum for a small fee. With the powercommander3 the tuning possiblilities are pretty vast. i havent heard anybody complain about needing to go to a bigger injector size from lack of fuel. i dont know too much about the ecu so somebody else will have to give more detailed information on this topic.

Tranny: So far I have had absolutely no problems at all with my kawi tranny. It always shifts smooth and i havent had any false neutrals post break-in. Reverse has always worked great for me and its extremely helpful in trails or occasionally when you spin out on a berm at the track(made me feel stupid :o ).
I've read a few stories of guys on balls to the wall built motors having 3rd gear go out but you gotta go with the old saying "cheap fast reliable. Pick 2".


anything else your curious about ill try to answer, its pretty late here and im falling asleep while typing this :p

[631kfx400]

im gonna use that in the next essay for school^^^
:blah: :devil:

[BLU82]

I've been racing motocross with them for nearly three years now. I've never had a problem with my batterys going dead, but all my harnesses are gutted. Other than my gas tank completley failing on my first year kfx, a problem which caused a recall and has been since been fixxed, I've had no major problems.
Motor: Once you go up in compression the stock rod has a pretty good chance of breaking. Carillo makes a much stronger replacement that solves this problem. Other than the weak rods on heavily modded motors I've seen no problems.
Frame: Never had any problem with my frame. I've only seen one cracked frame on one my pro friends quad. He landed on a rock off of one of the larger jumps at a notoriously rocky track. It was only a small hairline crack and I doubt a steel frame would've held up much better.
EFI: Once you take your time to learn your way around the various sensors and such, it is actually fairly easy to work on. The pcIII and now the pcV make tuning it fairly easy aswell

[tscracing]

I love mine. I have raced it going on 3 years. First year hare scrambles, then the past 2 motocross. I do maintain it though. anything in question gets tossed.

[MtnEX]

No major problems I know of mechanically or structurally.

Though I have read where a guy or two broke steering knuckles. That scares me.



I find owning one to be frustrating compared to Yamaha, Honda or Suzuki though...

The support out there is not massive when it comes to "peer feedback" like on forums, etc... not a lot of owners.

I liked the bike when I brought it home... then something went wrong, and I hated the complication of the EFI, ECU, Sensors, Wiring, Etc...

It's a pain to work out even the kinks and bugs. I for instance crawled all over it, pulled my hair out, and eventually surrendered... hauled it in to the dealer.

Dealer did the same dang thing, then gave up and put it back together. Luckily it was fixed. All that BS over just a bad connection.



Compared to the built YFZ... I just didn't like it in the woods... liked it otherwise, but not in the woods. I like the KFX better.

[hondaracer_34]

I agree ^^, i liked mine when i brought it home, bearing carrier went out the first month, replaced it ( thank god for the warranty ), then for the first year she was amazing. After the warranty went out, **** broke. I've had the worst luck keeping sprockets, chains, and sprocket hubs. I even had the dealer replace it the 2nd time, so its not me. The bolts are ****. Then my last ride, bye bye cases, damn chain snaps, hits the case. I havent had anything go bad with the electrical though. I love the quad to death dont get me wrong, but ive only road a few times this year and its sad.

[zjmr51]

are u guys keeping the chain tighten to spec so its not slapping causing it to break or weaken the sprockets....????
i have heard a lot of people have this prob and say bolts are tight and running bigger bolts and dif type of metal sprockets... but never mention if they keeping chain adjusted right.... i have looked at a few around the area and most of them have had the chains way to loose.... and slap LIKE H*** when trying to ride it, which is way to loose!!

-- may not help buts thats my (2 CENTS)...

[k4f5x0r]

i try to keep mine within spec, but it was really loose at one point and nothing ever happened to mine.

even when the chain is in spec, it still seems to make a sort of slapping noise when at lower speeds. never figured out why, i just got used to it i guess

We been trough a few cases on the kawi do the chain, One something got stuck in the sprocket and ripped the front sprocket out of the tranny.

Others happened because of broken sprockets. Mostly because the stock bolts always came loose and the sprocket had play and broke apart. If you drill out sprocket hub and run bigger bolts. and get your self a chain guide it would never happen.

And kawi chains are weird. You can have 4inch chain play at full extension and when compressed it can be super tight with less then a half inch. Thats where you have to be careful.

Besides electrical issues you will run into. Since there are a ton of wire and suggest a gutted harness if you decide to mx with it. We never have issues with them els wise. Motors run really strong and frames are holding with no issues.

[Jessem24]

dude keep your yfz. if its built then its even better. most of these kawi guys are having problems and its not worth it. i think you would be pissed after awile regreting your decision if you got a kfx. id keep the yfz in a heartbeat :eek2:

[k4f5x0r]

he's asking the kawi guys their opinion on them. you dont own either of the quads, so unless youve ridden both quads and can site examples of pro's and con's your opinion isnt to useful.

and please dont start with the, well my friends riding buddy's uncle had a kfx and he didnt change the oil for like awhole 3 hours and the transmission imploded into the top end causing the valves to flying into his crotch! :p

[Jigsaw]

I had only one problem and that was the chain popping and binding at the shifter taking a chunk outta the engine case.

Other then that its an awesome, reliable machine. I have not had any other problems for the 1 year I owned it. Handles great and feels real comfortable in the woods.

FWIW, I rode a 525 outlaw and my quad feels like it has more torque

[jimmyjames1700]

Originally posted by zjmr51
are u guys keeping the chain tighten to spec so its not slapping causing it to break or weaken the sprockets....????
i have heard a lot of people have this prob and say bolts are tight and running bigger bolts and dif type of metal sprockets... but never mention if they keeping chain adjusted right.... i have looked at a few around the area and most of them have had the chains way to loose.... and slap LIKE H*** when trying to ride it, which is way to loose!!

-- may not help buts thats my (2 CENTS)...

I check my chain tension before every ride to be sure it is within specs and it always still has a bit of a slap at low speeds. It is a bit better after it is freshly lubed though.

[DEVINF450R]

Do you guys think a TMM Chain guide would help this problem. It would keep more tension on the chain

[MtnEX]

Wow...

Dunno if I see you guys posting elsewhere about these problems... or if I see an issue developing with this over time.

I had been shrugging it off, but now I'm starting to be concerned.

What should I watch for?

[bryce3]

i race mx with mine. this year was my first year on the kawi. i had to start running bigger bolts on the rear sprocket cuz i kept snapping the others off. my rod broke and sent it thru the case. i hav blown about every fuse on it. i hav had alot more dnfs this year than i had last year on my suzuki. but now im pretty sure we hav all the problems ironed out and it runs great.

[WildWestRacing]

We just broke our 2nd set of sprocket bolts this past weekend. I should mention that our bike is a full blown Hetrick built race bike.

Just curious, what size bolts did you use to replace the stock ones with. Honda sprocket bolts seem like they will be too big.(Wont leave enough meat on the hub)

[Pappy]

We went through a set of spocket bolts as well. Drill them out and install the honda bolts