Author Topic: Rebuilds  (Read 3001 times)

0 Members and 1 Guest are viewing this topic.

Offline martinfan30

  • Sr. Member
  • ****
  • Posts: 456
  • 2000 KX500
Rebuilds
« on: February 04, 2009, 01:57:41 AM »
I've been told these cylinders cannot be bored. Is this true?
2000 KX500
2005 XR650L

Neither are stock, and both are great desert bikes.

Offline don46

  • Hero Member
  • *****
  • Posts: 1,140
Re: Rebuilds
« Reply #1 on: February 04, 2009, 03:31:26 AM »
Thats right, unless they've been sleeved, and assuming your talking about a K5
Live today, for tomorrow may never come

Offline martinfan30

  • Sr. Member
  • ****
  • Posts: 456
  • 2000 KX500
Re: Rebuilds
« Reply #2 on: February 04, 2009, 06:52:53 AM »
Yeah 500. Why is this and what are the options?
2000 KX500
2005 XR650L

Neither are stock, and both are great desert bikes.

Offline gwcrim

  • Hero Member
  • *****
  • Posts: 673
    • http://profiles.yahoo.com/gwcrim
Re: Rebuilds
« Reply #3 on: February 04, 2009, 07:42:48 AM »
A standard cylinder is 86mm and can be bored to 88 if you replate it.  Or you can put an iron sleeve in it.

Personally, I wouldn't sleeve one unless I had to.  However some people feel that the plated aluminum isn't as durable.

YMMV
~Crim~
You raise the blade
You make the change
You rearrange me 'til I'm sane

Offline don46

  • Hero Member
  • *****
  • Posts: 1,140
Re: Rebuilds
« Reply #4 on: February 04, 2009, 07:47:25 AM »
Your cylinder, assuming it is stock, is aluminum with a Nikasil coating (Nikasil is ha hard surface that will not wear, or at least not very much) if you tried to bore it you would be taking the hard coating off and be down to Aluminum, and we know how long a piston would work in that environment. You can have you cylinder re-coated, there are several companies that do it, US chrome, Millenium technologies and many others, for about $250 they will redo your cylinder to like new condition. If there is serious damage they can usually fix them. The other option is to sleeve it with a cast iron sleeve, you could then bore it to oversizes, I wouldn't do that unless you were looking for a big bore, then it might be a possibility. I would caution buying a cylinder off ebay, if you did you would probably have to have it coated as well.

Live today, for tomorrow may never come

Offline martinfan30

  • Sr. Member
  • ****
  • Posts: 456
  • 2000 KX500
Re: Rebuilds
« Reply #5 on: February 04, 2009, 03:06:02 PM »
How thick in thousandth's is the Nikasil coating?
2000 KX500
2005 XR650L

Neither are stock, and both are great desert bikes.

Offline Friar-Tuck

  • Hero Member
  • *****
  • Posts: 1,827
  • \o/ Live Free or Die
Re: Rebuilds
« Reply #6 on: February 04, 2009, 05:24:12 PM »
 What is Nikasil ?   http://en.wikipedia.org/wiki/Nikasil
 
(Scroll down to post#38 for a peek at newly re-plate)
http://www.kxriders.com/forums/index.php/topic,4918.30.html   

Max Power
http://www.maxpower-engines.com/plating-and-repair/cylinder-express.html
 
Tuck\o/
« Last Edit: February 04, 2009, 05:33:06 PM by Friar-Tuck »
"The Truth Has No Agenda"

Offline tharden

  • Full Member
  • ***
  • Posts: 109
Re: Rebuilds
« Reply #7 on: February 05, 2009, 01:08:28 AM »
I believe Nikasil is a mixture of chromium and nickel.  It can either be plated or sprayed.  I have read where a plating company mixes carbide with the nikasil and makes the cylinder last much longer.  With a dirt bike turning high rpms and limited cooling due to some riding conditions a plated cylinder is the best choice.  Too me $250.00 is not a lot of money to keep a functioning kx500 running and especially if it lasts 5 to 10 years.

Offline martinfan30

  • Sr. Member
  • ****
  • Posts: 456
  • 2000 KX500
Re: Rebuilds
« Reply #8 on: February 05, 2009, 01:51:15 AM »
Not that mine needs it, just gathering as much info as I can on this beast. I really appr. all the info guys.

If there is some damage, they can fix the aluminum part, then replate it back to std. bore...
2000 KX500
2005 XR650L

Neither are stock, and both are great desert bikes.