KX Riders

Maintenance & Technical => KX500 Original => Topic started by: shostang on May 27, 2009, 12:12:16 PM

Title: Items prone to fail on the 500?
Post by: shostang on May 27, 2009, 12:12:16 PM
Does anyone have some sort of list of things that are known to fail on these bikes?  Just so I can address them before the race and have a smaller chance of something breaking/failing.  I'm rebuilding the bike for the Vegas To Reno race this summer, and want to make sure everything has been addressed.  Sorry for the noob questions, my main bike is a YZ426 and I bought the 500 specifically for this race.

Thanks for the help.  :-D

Title: Re: Items prone to fail on the 500?
Post by: jfabmotorsports.com on May 27, 2009, 12:31:22 PM
The YZ426 is what made me buy a KX450f. I still have the 426...love it. If the 500 is used it more than likely needs all the linkage bearings replaced. I have bought countless used 500's and not one has had a full set of good swingarm/linkage bearings. Next, check crankcase seals. Those have been my two problem areas.

JAFB
Title: Re: Items prone to fail on the 500?
Post by: Mick on May 27, 2009, 12:33:56 PM
Does anyone have some sort of list of things that are known to fail on these bikes?
Everything  :-D
...but here's a few things mine breaks continually, in no particular order:
1.  Pipe mounts
2.  Silencer bracket
3.  Drive side rear hub bearing
4.  Kickstarter
5.  Every fastener not loctited disapears
6.  Frame behind the engine cradle, near the footpeg brackets crack
-and a few isolated episodes:
7.  Plating came off the carb slide
8.  Electrofusion flaked off the cylinder (caused a huge d**n mess)
9.  Water pump impeller ground it's teeth away

But I've never had any infamous tranny or otherwise engine related problems aside from the above isolated incidents.
Title: Re: Items prone to fail on the 500?
Post by: KXcam22 on May 28, 2009, 02:44:22 AM
Your Nerve.........
Title: Re: Items prone to fail on the 500?
Post by: jdcowboy on May 28, 2009, 03:34:33 AM
Your Nerve.........
Definitely get some extra doses of nerve.

My recommendation would be go over the bike really good check every nut, bolt screw on the machine to make sure they are tight.  When I got mine they all needed to be tightened.  Still I lost the exhaust bolts.  Locktight can be your friend....until you have to remove that item again anyways.

Good luck.
Title: Re: Items prone to fail on the 500?
Post by: turtle22 on May 28, 2009, 03:48:57 AM
it would not hurt to have the shock rebuilt. ive have to do that on both my 500 that i desert race. they take a pretty good pounding out there. the seal head likes to leak after awhile.
Title: Re: Items prone to fail on the 500?
Post by: Polar-Bus on May 29, 2009, 12:46:39 PM
Does anyone have some sort of list of things that are known to fail on these bikes?  .  :-D



The rear tire knobbies?
Chains and sprockets ?
Your forearms?       :)
Title: Re: Items prone to fail on the 500?
Post by: Johnniespeed on May 30, 2009, 02:08:42 PM
 Pipe mounts
 Pipe mounts
 places where the pipe mounts attach too
  Rear tires
  knobs on rear tires
 Did I mention pipe mounts and rear tires ?
Title: Re: Items prone to fail on the 500?
Post by: turtle22 on June 03, 2009, 04:01:59 AM
oh and most important thing that is common to fall of; the rider(if not holding on tight) :lol:
Title: Re: Items prone to fail on the 500?
Post by: barryadam on June 03, 2009, 04:41:50 AM
The above posts list the first items to go.  But on the KX500, EVERYTHING is a wear item.  And I mean EVERYTHING.  I've replaced a cracked airbox, Baja Designs dual sport stuff (horn, horn mount, metal headlight bracket, blinker relay, headlight wiring connection, headlight, etc.) all from wear, not crash damage.  My rear license plate and rear led light both broke from the vibration!  Renthal fatbars cracked (Ok, so those might have ben a manufacturing defect). The radiator screens fall off because the mounting holes in the radiator's aluminum flanges have enlarged so much.  The tank/radiator shrouds crack from the vibration.

I've had my crank aligned and all new bearings in the motor, so it's not an engine maintenance root cause.

I don't seem to be distributing fasteners all over the landscape like other folks, and I have not been using Loctite.

Oh yeah, one of the "fail" items right up there with the pipe mounts is that the chain grinds it's way through the subframe leg.
Title: Re: Items prone to fail on the 500?
Post by: Johnniespeed on June 03, 2009, 12:15:22 PM
 A little clear RTV silicone on the plastic radiator grills at the mounting pegs will keep you from spending fifteen dollars at the dealer.
 I bought a nice big bag of those special 8mm hex head 6mm bolts from a member here, I plan to distribute them all over the landscape, so when other KX500 owners need one, all they have to do is look down.
 What is  the high score for number of pipe mounts broken ? 
John
Title: Re: Items prone to fail on the 500?
Post by: demographic on June 08, 2009, 11:57:15 PM
This thread might help you out with some of the faults and fixes...
http://www.kxriders.com/forums/index.php/topic,434.0.html (http://www.kxriders.com/forums/index.php/topic,434.0.html)
Title: Re: Items prone to fail on the 500?
Post by: Ahole500 on June 10, 2009, 02:10:13 PM
i've killed 2 kickers,snapped rite off.
Title: Re: Items prone to fail on the 500?
Post by: martinfan30 on June 10, 2009, 02:57:09 PM
i've killed 2 kickers,snapped rite off.

Curious, where are the kickers prone to fail? Where do they break? With a good kick start routine, can this be avoided?
Title: Re: Items prone to fail on the 500?
Post by: snoopjonnyjon on June 16, 2009, 09:36:51 AM
Well, I've owned my KX500 for about two weeks, and it seems the weaknesses listed are true. This is on a one owner, original tire (since replaced if you noticed the Maxxis rear on it) bike I bought that he estimated had around 20hrs total time, not an old clapped out raced bike.
(http://i106.photobucket.com/albums/m252/snoopjonnyjon/nisbet021.jpg)

Upon getting it home I noticed the subframe was worn by the chain. After reading the pipe mount tab on the frame breaks off, I discovered that was also the case on mine. And the last time out riding it I broke two of the little rubber pipe mounts, and broke off the kick start lever (apparently 02-04 levers are beefier, so that is what I ordered). I also lost the bolts that hold the silencer to the subframe.

Also, the little rubber cones in the top triple clamps were distorted which made the handle bars look bent. And the lower pipe spring was lost, presumed broken.

And as other people have said, they like to eat rear tires, and drink a lot of fuel!
Title: Re: Items prone to fail on the 500?
Post by: Ahole500 on June 29, 2009, 02:42:13 PM
i've killed 2 kickers,snapped rite off.

Curious, where are the kickers prone to fail? Where do they break? With a good kick start routine, can this be avoided?
all mine broke at the pivot point,the part and the shaft breaks.the main part of kicker just wears a groove into the monting part and makes it weak and snaps in half.i wish i could find a billet one and not the cast b/s
Title: Re: Items prone to fail on the 500?
Post by: DoldGuy on June 29, 2009, 03:02:54 PM
We do have some gifted machinist here on this forum. Anyone??
Title: Re: Items prone to fail on the 500?
Post by: martinfan30 on June 30, 2009, 02:03:33 PM
We do have some gifted machinist here on this forum. Anyone??

Only problem with that is, I'd rather have the kicker break at that point. Instead of strengthening the kicker and finding the next weak point inside the case.
Title: Re: Items prone to fail on the 500?
Post by: JohnJr on June 30, 2009, 02:43:12 PM
People"s smile when you blast past them on a kx500!!!!!!
Title: Re: Items prone to fail on the 500?
Post by: Ahole500 on July 01, 2009, 02:50:19 PM
We do have some gifted machinist here on this forum. Anyone??

Only problem with that is, I'd rather have the kicker break at that point. Instead of strengthening the kicker and finding the next weak point inside the case.
good point
Title: Re: Items prone to fail on the 500?
Post by: snoopjonnyjon on July 02, 2009, 04:53:24 AM
I got my replacement kicker earlier this week, and the 04 kicker was definately slightly beefier than the 98. I'll find out if it holds up or not.
Title: Re: Items prone to fail on the 500?
Post by: BDI on July 02, 2009, 10:56:07 AM
People"s smile when you blast past them on a kx500!!!!!!
:lol: :lol: :lol: :lol: Sure they do :lol: :lol: and then they sing the happy happy joy joy song as they pick the rocks out of their teeth  :lol: :lol: :lol: :lol: :lol:
   

                       http://www.youtube.com/watch?v=QqGsxwQpa_g&feature=related