Is the piston considered bad when...

[ShanMan]

...it looks like this:



The top of the piston reads: F48N8N on the rear top lip, and STD 575PS 10 on the center.

The bike is an '87...I went to the Kawasaki site and looked up the part number for a stock piston. It gave me 13001-1245. It also only shows one piston ring, and the piston in my bike has two as you can see. Does anyone know who the manufacturer is of the piston that is in my bike? Better yet, does anyone know if a later model (stock or aftermarket) will fit my application? FYI: the bore on my cylinder measured out at 86.05mm with my digital calipers. According to '87 specs, the bore and stroke are a perfectly square 86 X 86mm. Is this true for '88 and up?Please help!  

<edit> I found that the majority of piston kits are good from '88 up to present. I also discovered that they have two piston rings like mine does. Can anyone shed some light on the other differences...i.e. skirt lengths or perhaps crown shape? The piston in the bike is a flat top.....help.

[woodsy]

Hi Shanman:
That 575ps is a Wiseco (sp) Stock piston for your 87.  The Wiseco brand uses "ps" to designate stock, "p2" would be 1st over, "p3" second over and so on...  It is the correct piston for your bike.
Want my opinion about what happened to your  piston.  IMHO, you had some major predetonation happening.  Could be caused from running lean or even running to low of octane fuel.  Do you remember hearing spark knock?
Hope this helps
Woodsy

[ShanMan]

Thanks Woodsy...yes, it had been knocking quite a bit, so more than likely, you hit it right on the head. We have been running 32:1, so it was oily enough that it probably prevented a major meltdown. Guess premium pump gas is out, and VP racing gas is in huh? Thanks again.

Perhaps most importly however, is where I can get a replacement piston, and pronto?! The whole point of fixing the gasket (which revealed this problemo) was that this coming weekend is my first ride after two months off with a broken wrist. I will be very bummed if I have to sit it out.

[sdkx500]

Long Beach?  Try Chapparal Cycle in San bernadino @ (800) 841-2960.  Might have it in stock and you could pick it up.  You could see if Monkeybutt racing would fedex you one.

T

[mikesmith]

I got a Wiseco piston,rings,pin,bearing,clips and gaskets for $139.00 with free shipping and no tax from MotoSport.com.They have Vertex and I think Pro-X kits also,shipping was in 4 days.I was happy.Im not sure what to say about that piston in your bike other than thats scary!

[Paul]

Shannon, with that damage on the exhaust side of the jug what does the nikasil look like around the exhaust port? Still shiney hopefully and NOT flaking.

[ShanMan]

Actually Paul, the cylinder looks really good. There is no flaking and no scoring at all. Even the cumbustion chamber in the head looks perfect with virtually no carbon buildup. I think running it at 32:1 really saved the cylinder...of course, not riding for 8 weeks might have helped too!  

[Zombie]

I ran an '88 sleeve AND '88 piston in my '85 without any trouble. It just looked slightly funky with extra exhaust ports that didnt go anywhere.

-BTW- yes, it is bad when your piston looks like that

-Z

[ShanMan]

Alrighty then....saga number two: how to get a stubborn wrist pin out without using some fancy-shmancy puller tool???    

[woodsy]

Take a socket that is large enough to let the pin into, cover the leading edge of the socket with duck tape about 4 layers thick so it dont mar the piston, take a knife and cut the center portion of the tape out so the pin can go in.  get another socket that will fit inside of the pin hole (probably have to be a deep well).  Put sockets in place and drive the pin out with a C-Clamp - WORKS GREAT!!  
Hey, sometimes you have to resort to "creative thinking" when working on this stuff ))
Wanna hear how I ground the valves in my XR one time.......
Woodsy

[ShanMan]

Well Woodsy, we must be psychically linked! While you were posting this, I came up with almost the exact some solution minus the duct tape. I couldn't give two Hondas what happens to the piston...it's pretty much a paper weight now. I used a 6" 3/8" drive extension with a flat piece of steel across the end (to push on) and then drove the whole thing out with a big 12" C clamp. The one thing I did before that was to brush some Easy-Off oven cleaner onto the ends of the wrist pin to break down any carbon buildup that might be trying to keep the pin in. It worked great! So now it's time to put in a new piston kit and get to back to my normally scheduled program....Roostin'! Thanks again one and all.