piston ring 1st over

[FUBAR]

i have a snapped ring on one piston, being that the stock rings are so hard to come by, if i use 1st over rings will i need a larger piston also .. or will they work with stock pistons

i know that on 3rd over you need the larger sized pistons which are 60 bucks a pop.

thanks

 

[xschris]

You will need a .25 piston to go with a .25 ring

 

[HoughMade]

Yep ring must match the piston....and first over pistons aren't too easy to come by either.

 

[volcomskater77]

if your going to go with an over bore, OVER bore it. like 4.00 over. think im gonna do that with my 125. seeing as tho NOS 4.00 over piston and ring kits are 20 bucks.

 

[FUBAR]

yea i agree with you Volc. i just thought i might not need to buy the pistons this way. wheres this kit you speak of??

 

[lhaolpa]

i have a snapped ring on one piston, being that the stock rings are so hard to come by, if i use 1st over rings will i need a larger piston also .. or will they work with stock pistons

i know that on 3rd over you need the larger sized pistons which are 60 bucks a pop.

thanks

Is the cylinder scratched? Sometimes,the rings can break and not do much damage,and can be repaired with just rings and a light honing to crosshatch the cylinder. Look on Ebay,The rings and pistons sometimes come up on there,you just have to refine your search to find the parts you want.I found a jug,head,carb boot,head gasket,and piston w/ rings for my dirt bike for $20.00 + shipping.Good luck. lha

 

[xschris]

Remember you have to change both pistons when you do it. Finding a new set is not cheap or easy. I got a set of .50 pistons and rings from yamaha about 4 years ago and it was like $300 I did not need them I got them to hold on to when I did. They had to ship them from japan because there was only a few left. I don't think you can get them from yamaha any more

 

[lhaolpa]

if your going to go with an over bore, OVER bore it. like 4.00 over. think im gonna do that with my 125. seeing as tho NOS 4.00 over piston and ring kits are 20 bucks.

Where the heck are you getting your pistons and rings at $20.00? I am looking for OS piston and rings for a 400mx jug that I got to modify my '75 Dt400,and they cost over $200.00!!!!Please give me the link or name of the place!!! lha

 

[lhaolpa]

i have a snapped ring on one piston, being that the stock rings are so hard to come by, if i use 1st over rings will i need a larger piston also .. or will they work with stock pistons

i know that on 3rd over you need the larger sized pistons which are 60 bucks a pop.

thanks

If your cylinder and piston are not ruined,You can clean up the piston,cylinder,and use the same piston,jug and just replace the rings. If they are toast,then get OS pistons and rings and go at it! lha

 

[volcomskater77]

ebay. they have AT2 rings and piston over size kits NOS for 20 bones

 

[lhaolpa]

Pistons for my Mx400 are 86.50mm,Wiseco #232mo8650 $212.97.That's just for a piston,not including rings,pin,bearings.I should add that I'm still looking.That is for an over-oversized piston.Yamaha only sells up to 1mm over,I'm at 1.5mm OS.That's 403cc,instead of 397cc . lha

 

[FUBAR]

@ihaolpa the only problem is i have never in my life seen a set of NOS stock sized rings for sale on ebay or anywhere. do you know of a spot?

and no the cylendars/pistons are in fine condition no scratches ect

 

[lhaolpa]

@ihaolpa the only problem is i have never in my life seen a set of NOS stock sized rings for sale on ebay or anywhere. do you know of a spot?

and no the cylendars/pistons are in fine condition no scratches ect

Have you called or gone by your local Yamaha shop?Google "piston rings,Yamaha" and you'll find Wiseco,who sells pistons,rings,etc.There will be others as well who sell rings and related items.I did the same thing yesterday,and found what I was looking for,then searched on ebay,and found a store on there that had my piston,rings much cheaper,1/2 price for Wiseco piston set. You gotta look for it!! oemcycle.com lha

 

[xschris]

Looked at there site oemcycle.com and did not see any for a xs400, did I miss it?

 

[lhaolpa]

google yamaha xs400 piston rings. lha

 

[lhaolpa]

Just found on Bike Bandit,Piston Ringset std #116358,$66.77.There are others,You have to select your bike info when it asks for make,model,etc. Hope you get your bike running without anymore problems.Good luck. lha

 

[khales]

Maybe someone who has done this before can give me a little insight. I've never changed piston rings on a motor before and I'm gonna have to pull the head and put a new gasket on in the next few days due to some major oil leakage. I wanted to go ahead and put new rings in when I pulled it apart. However, I'm not too sure on which rings i'll need to change since there are 4 different ones per piston. Do I need to change all 4 on each if I'm going to do it or just 1 of the rings per piston?

 

[drewpy]

I'd change all 4 and hone the bores. its a diy job for both ( I borrowed a honer off a mate)
rings are brittle so don't stretch them too far out or PING!

 

[khales]

Alright thanks Drewpy. I was really hoping I wouldn't need to change all 4. Those things are retardly expensive.

 

[drewpy]

why do you need to change them? just 4 kicks or something more serious?