replacing piston rings question.. should i do both?

[FUBAR]

i have a snapped ring on one piston, but the other piston is intact and looks to be o.k...

im ordering a new ring set but should i just replace the damaged side or replace both sides and get the whole thing honed?

 

[lhaolpa]

If the cylinders are not scratched deeply,you can just replace the ring although you'd be better off re-ringing both cylinders.Get a new ring,put it squarely in the cylinder about 2" into the cylinder,and measure the gap in the ring. Compare the gap with the specs in the manual.If it's in the range,go for it. New rings all around will get you more compression,power. lha

 

[khales]

Fubar when you do end up ordering the rings, post up where you got them from. I've been looking for a set for my 77 but they are ridiculously expensive.

 

[drewpy]

hone the bores too, it takes seconds to do

 

[FUBAR]

the ones im looking at are like 70 bucks a set, which is just retarded in my opinion but theyre impossible to find elsewhere

 

[Lepttack]

If you hone the bore is there anything else you need to do before putting the rings back in or do lyou just fire 'em in there when you're done?

 

[drewpy]

you'll have to bed them into the bores (by riding the thing)

two schools of thought;

1) ride it like you stole it for 20 miles on mineral oil and change oil

2) gently build up the load on the engine to bed them in.

I subscribe to #1 did my bike 6 years ago, total rebuild and doesn't smoke.
honed the tracker bore and will do the same to that too!

 

[Grayum-Rig]

Found the STD size rings here for $50 I haven't ordered mine yet but will soon enough.

http://www.boats.net/parts/detail/yamaha/Y-2A2-11610-00-00.html?CAWELAID=976938584

 

[vfost]

Found the STD size rings here for $50 I haven't ordered mine yet but will soon enough.

http://www.boats.net/parts/detail/yamaha/Y-2A2-11610-00-00.html?CAWELAID=976938584

Careful! that looks like you need to order a qty of 2 at $50 apiece! but none the less atleast you found some.

 

[lhaolpa]

you'll have to bed them into the bores (by riding the thing)

two schools of thought;

1) ride it like you stole it for 20 miles on mineral oil and change oil

2) gently build up the load on the engine to bed them in.

I subscribe to #1 did my bike 6 years ago, total rebuild and doesn't smoke.
honed the tracker bore and will do the same to that too!

As long as you don't maintain a steady speed for too long,you'll be OK. Getting a new car,for example and going on a long vacation driving across the country at 70 mph is the perfect way to assure a short life for your rings,while driving across town to work is about the best way to set the rings as the motor isn't under much stress and shouldn't get too hot. lha

 

[Grayum-Rig]

That's correct, This was the cheapest place I found. Other places ether didn't have the rings in stock or wanted around $80 a set.

 

[lhaolpa]

Have you done a search on ebay? Just put "rings,xs400 Yamaha",and see what happens.I've seen lots of ring sets for cheap while perusing the files on ebay. lha

 

[FUBAR]

ebay was my first try but i could never spot a STD set, mostly 3rd and 4th over.. and i tried going that route and buying the corresponding pistons only to find they have been discontinued. i didn't want to end up with 2 new 4th over ring sets and only one 4th over piston and be stuck.

i just accepted the brutality of the bike bandit price and bucked up. ouch it still hurts..

 

[lhaolpa]

Yeah,some things are hard to find,and if you want them now,you have to bite the bullet.Hope you get it running well and without much probs. That being said,there's a whole motor for $100.00 on ebay. lha