Piston Slap?

[Longview]

tell me what kind of piston you want and what size it has to be and I'll find the lowest price for ya I got plenty of time online.But if your getting a piston make shure it's forged they last a good bit longer.here you go just click the link also amsoil dominator will make your piston last longer that that yamalube your probably useing ok. also keep in mine going through a dealer will end up being an easy 40-50 dollars more than the piatons in the links ok. also RJ-atv is a very reliable and trustworthy company I just got my 50 over piston for $85 no gaskets without a hitch
Yamaha Blaster Wiseco STD Piston Gaskets Bearing Kit | eBay
Yamaha Blaster Wiseco .Std (66.00)mm Piston Kit YFS200 | eBay

Wow, thank's a lot man, when i get the money for a kit I'll totally PM you to see if you still interested in helping. Thanks. +Rep I:I

 

[Longview]

Numbers on the piston.

Center number: 573MO6600

Closest to intake: 7529A

I don't have any PB Blaster to get this muck off, but that's what i could read, could be wrong letters/numbers.

 

[Racer51]

Great I like making new friends. SBut yea shure thing I'm on here at least once or twice a day if i can help it (chuckle). Just so you know the last 4 numbers 6600 on the piston are the size of your piston you see 66MM is the stock size of it, and the japaneese use Millimeters or commonly MM as their unit of measurement.

 

[Longview]

Great I like making new friends. SBut yea shure thing I'm on here at least once or twice a day if i can help it (chuckle). Just so you know the last 4 numbers 6600 on the piston are the size of your piston you see 66MM is the stock size of it, and the japaneese use Millimeters or commonly MM as their unit of measurement.

Alright so that means i need a 66MM piston correct?

 

[Blaaster]

Spot on.

65.965mm - 66.00mm measured 10mm up from the bottom of the skirt.

 

[Longview]

Spot on.

65.965mm - 66.00mm measured 10mm up from the bottom of the skirt.

Do you think after i hone my cylinder i should take it to a machine shop to see if it's still that size?

 

[Blaaster]

Honing will take very little material off the cylinder and measuring is not needed.

If you feel the cylinder is worn or marked badly it should be bored.

 

[Longview]

Honing will take very little material off the cylinder and measuring is not needed.

If you feel the cylinder is worn or marked badly it should be bored.

It's not even scratched, just like, black scuffs from it running for 12 years. I just didn't know if it took off a lot.

 

[Blaaster]

It's not even scratched, just like, black scuffs from it running for 12 years. I just didn't know if it took off a lot.

You would have to run that hone for a long time to take too much off.

I am assuming that you only ran it long enough to obtain a full coverage cross hatching.

If you had to run it for a long period of time to remove imperfections it may be that the bore is out of specs and requires a rebore.

 

[Longview]

You would have to run that hone for a long time to take too much off.

I am assuming that you only ran it long enough to obtain a full coverage cross hatching.

If you had to run it for a long period of time to remove imperfections it may be that the bore is out of specs and requires a rebore.

Full coverage cross hatching?

 

[Blaaster]

Full coverage cross hatching?

All surface showing hatching, no shiny bits.

 

[Longview]

All surface showing hatching, no shiny bits.

Oh no, i don't know how much you can see from the pictures, but it's not that bad.

 

[Blaaster]

If there are no shiny bits from previous piston ring wear, you should be good to go!

 

[Longview]

Alright, i think I'm good then.

 

[Blaaster]

Alright, i'll be sure to look at that when i do the full tare down.

But here are those nasty photos i was talking about.

Just had another look at these pics, it looks like something has been smashing around in there, like a reed screw or the earth electrode of a spark plug.

Lets hope that it went out through the exhaust port.

Did you say the screws were all still in the reeds?

 

[Longview]

Yeah on my Cylinder head right? I actually didn't check, do you mean, the screws mounting it, or the screws internally?

 

[Blaaster]

The screws that mount the reeds to the housing, they are only little and will vibrate out if not fitted with Loctite.

 

[acezeesawtooth]

the cylinder walls might look good. but when it you take it to the shop and i cannot stress this enough. have them measure and make sure the cylinder is still in round. running for 12 years is hard all that heating and cooling causes the cylinder to warp out of shape. if its still round then no problem hone rings and go. but if its not you may need a bore

 

[Longview]

the cylinder walls might look good. but when it you take it to the shop and i cannot stress this enough. have them measure and make sure the cylinder is still in round. running for 12 years is hard all that heating and cooling causes the cylinder to warp out of shape. if its still round then no problem hone rings and go. but if its not you may need a bore

Alright, I'll have someone look at it, And what should i do with the cylinder head?

 

[Blaaster]

Sealing surface looks good enough to clean up with a greenie or fine steel wool.

If you are concerned about warpage, lightly, I mean very lightly, smear some sewing machine oil on it and place it on a sheet of glass.

Look at the head sealing surface through the glass, if it is bad you will notice no oil sticking to the glass where it is warped.

The imperfections in the combustion chamber should give you no greif, leave them as they are.