Kx 500 help!

mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827
Edited Date/Time 7/14/2018 12:48pm
So I’m throwing a top end in the bike I just bought..
The bike ran before tear down.. I pulled the reed cage and found this!?!?

1)the piston color? Old gas that got by rings and sat or?
2) the black coating that is bubbling and flaking off.. I saw the bubbling and flaked it off with my finger nail.
3) how to clean this black coating? Acetone,cleaning foam, blaster cabinet or let the 500 chew it up! Hahaha
Thanks for the advice





|
mxers37
Profile picture for user mxers37
Posts
32
Joined
7/9/2018
Location
Lancaster, CA US
mxers37 7/12/2018 5:23pm
7/12/2018 5:23pm
i would pull the cylinder off and chem clean it, that doesn't look normal. lol
mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827 7/12/2018 5:26pm
7/12/2018 5:26pm
Haha I know it’s not normal!! Is chem clean a diy or a shop deal
mxers37
Profile picture for user mxers37
Posts
32
Joined
7/9/2018
Location
Lancaster, CA US
mxers37 7/12/2018 5:32pm
7/12/2018 5:32pm
shops have chem tanks, if u use some sort of solvent it should take the black coat off. Im not sure what the black coat does or why its there, on all my 2 strokes there is no film, i use a solvent from tractor supply that works pretty good and A chem tank from harbor freight
mxers37
Profile picture for user mxers37
Posts
32
Joined
7/9/2018
Location
Lancaster, CA US
mxers37 7/12/2018 5:34pm
7/12/2018 5:34pm
It could be caked on oil from running really rich possibly, hard to tell in the pictures. You cpukd use contact cleaner and a brush or scotch bright.
1

The Shop

See All »
Joko
Profile picture for user Joko
Posts
1433
Joined
1/2/2011
Location
Cromwell, CT US
Fantasy
190th
Joko 7/12/2018 9:54pm
7/12/2018 9:54pm
I believe some of the KX500 cylinders were painted as an OEM process.
mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827 7/13/2018 8:11am
7/13/2018 8:11am
Ya Tom Morgan says it’s OEM paint?? Super weird to paint that area but whatever...

Next question is the piston color/lacquer.. there are no digs, scratches piston is smooth only thing I noticed was the bottom ring was tight as hell but top ring was good.. the top of piston looks t have a good burn tho, right?






mxers37
Profile picture for user mxers37
Posts
32
Joined
7/9/2018
Location
Lancaster, CA US
mxers37 7/13/2018 8:35am
7/13/2018 8:35am
The top is it has good burn should be a shape of a heart not the whole piston, definitely ran rich
DynoDan22
Profile picture for user DynoDan22
Posts
775
Joined
9/7/2011
Location
Victorville, CA US
DynoDan22 7/13/2018 9:30am
7/13/2018 9:30am
The black coating on the reed cage portion of the cylinder is a rubber-like paint that the factory applied. Kawi used to put this in all of their intakes until the late 90's or early 2000's. It does chip and flake off, not an issue. The burn fuel on the intake skirt isn't ideal and probably time for a top end.
mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827 7/13/2018 10:15am
7/13/2018 10:15am
The crank is the same color as the piston. But is in spec
Paw Paw 271
Profile picture for user Paw Paw 271
Posts
3640
Joined
4/3/2013
Location
Benton, LA US
Paw Paw 271 7/13/2018 10:26am
7/13/2018 10:26am
Running rich and also run too long between top ends as it shows a lot of blow by.

Paw Paw
KDXGarage
Profile picture for user KDXGarage
Posts
2562
Joined
12/16/2010
Location
AL US
KDXGarage 7/14/2018 6:29am
7/14/2018 6:29am
WOW. That is a lot of blow by. You ran it way too long. It is hard to tell anything about the top since you ran it way too long. If one tries to accurately read a piston top, it is during a normal service interval.
mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827 7/14/2018 9:18am
7/14/2018 9:18am Edited Date/Time 7/14/2018 9:22am
KDXGarage wrote:
WOW. That is a lot of blow by. You ran it way too long. It is hard to tell anything about the top since you ran...
WOW. That is a lot of blow by. You ran it way too long. It is hard to tell anything about the top since you ran it way too long. If one tries to accurately read a piston top, it is during a normal service interval.
I bought the bike and haven’t rode it, so I don’t really know how it ran even.. but it’s smooth with no digs or gouged and getting a gas bath.. and it’s cleaning really well. I’m gonna clean it and then hone it and put a piston in.. I’m soaking the crank too but am on the fence about what I’m doing after that.. pull apart and rebuild or soak in oil after this and run it.. by the way the crank doesn’t have any slop and is in spec up and down and side to side
mwssquad827
Profile picture for user mwssquad827
Posts
1463
Joined
8/4/2016
Location
Twin Falls, ID US
mwssquad827 7/14/2018 12:48pm
7/14/2018 12:48pm
KDXGarage wrote:
Is the cylinder sleeved??
Yup and currently has a B piston. So after I clean I’m gonna measure to make sure a B can go back in.. if not it’s off to millennium..

Post a reply to: Kx 500 help!