KX Riders

Maintenance & Technical => KX100 / KX85 / KX80 / KX65 / KX60 => Topic started by: DAGGITS on August 08, 2008, 02:35:52 AM

Title: big end bearing replace
Post by: DAGGITS on August 08, 2008, 02:35:52 AM

My son's friend was afraid to leave 2nd gear.  even at high speed.  The result was a seized lower end bearing.  I am somewhat mechanical and have a good understanding of the 2stroke.  Can I replace this bearing and inspect the lower end myself, or do I need special tools?  willthe bearing need to be pressed out?  I am more of what you would call a "parts changer" than a mechanic.  but I have no fear when it comes to trying.

Title: Re: big end bearing replace
Post by: DAGGITS on August 08, 2008, 02:37:03 AM

Please let me add that it was a lower end piston rod bearing.

Title: Re: big end bearing replace
Post by: DAGGITS on August 08, 2008, 02:39:03 AM

and let me add that it was a kx100 2001.   

Title: Re: big end bearing replace
Post by: DAGGITS on August 10, 2008, 04:23:17 AM

well , i seem to be the only one replying , but I decided to buy the whole crank and install it myself. Tearing down the old crank and replacing the bearing is just a littleabove my head.

Title: Re: big end bearing replace
Post by: Wizzy214 on October 27, 2008, 03:32:26 PM

post some pics of the progress.

Title: Re: big end bearing replace
Post by: KXcam22 on October 28, 2008, 03:51:00 AM

Daggits,
  As a suggestion check what 2-stroke oil your friend is using.  I had an expereince with a friend who blew up their KX60 a number of times, lower end rod bearing each time from overreving.  They were using the "dealer" recommended oil which was a low grade injector oil that was not really meant as mixing oil.  I got them to switch to a more expensive high grade synthetic 2-stroke oil and their problems went away.  They then figured out that the "expensive" oil was actually the cheaper one to run. A $3000 lesson.  Cam.

ps I witnessed the dealer recomend this oil to a number of KX owners.  Must increase his business.

Title: Re: big end bearing replace
Post by: hughes on October 28, 2008, 06:53:08 AM

To replace the big end bearing you would need to press the big end pin out of the crank shaft halves, and you'll need a special devise for tune / balance the crank once new rod and bearing was replaced. You made a good choice to buy a complete crank kit since they are priced about right. Might be a good time to replace crank main bearings and complete top end while your there.

Title: Re: big end bearing replace
Post by: lumpy790 on September 15, 2009, 11:20:06 AM

I do not know if they are making kits for 80's yet but I just picked up a Wiseco Bottom end kit for my YZ250 that included a complete crank, main bearings, piston bearing, seals and gaskets......and retails for only $216

Mind you that I could have pressed & trued the crank my self....but bought it all ready to install.