piston to a steel sleve?

[helio lucas]

the bike is a 92 yz125 i think, still have not checked, and is from a friend. it´s used only as play\trail bike...
the cylinder is cracked where the sub exhaust ports connect the main exhaust port, so the cheapest option is to go for a steel sleeve... i can have one made if i port it for 80 euros, more or less 100 dollars, fine for me...
now the question: stock piston and rings will be fine? i was thinking in a pro-x piston because they are cheaper, but will the rings will do ok in a steel bore?

thanks in advance :cool:

 

[julien_d]

Only three choices really, sleeve, weld and replate, or replace the cylinder. pro-x piston and rings will do fine in a steel bore. I'm curious about having one made if you port it? You should be able to find a wiseco or la sleeves sleeve for about 80USD.

J.

Like so....

http://cgi.ebay.com/ebaymotors/YAMA...2779335QQptZMotorcyclesQ5fPartsQ5fAccessories

 

[TRexRacing]

It's the ringset that will or will not like the bore.Pistons could care less.I'd send it away and have it repaired and re-plated.Just my preference.

 

[helio lucas]

It's the ringset that will or will not like the bore.

that´s my doubt... which will do fine?
if it was mine i go for a new one, but the person in question just will not spend that money and also doesn´t matter if the bike make good power or not. he was riding with a cracked cylinder, non working power valve and the water pump do not work at all, and he likes it :|

i have phoned several shops for a sleeve and any has them. the importer don´t import it. they import wiseco and pro-x pistons but not sleeves.

 

[TRexRacing]

Chrome plated rings don't like chrome cylinders.Ductile iron or molybdenum coated iron rings are preferred by chrome cylinders everywhere.

 

[helio lucas]

so, may i assume that stock or pro-x rings are just fine to run in the steel sleeve?

 

[whenfoxforks-ruled]

Its early in the morning here, but, I thought it was iron bores like iron rings, chrome bores like chrome rings. And the liner bores take "liner" rings? Hit these guys up with an email Helio, they know best! http://www.wiseco.com/

 

[TRexRacing]

From Hastings website.All they do is rings.

 

[helio lucas]

Its early in the morning here

what?!?! i´ve lunched 3 hours ago... you guys sleep too much ;)

it is pretty much common sense around here that it cannot be used chrome rings in chrome bores... old air cooled sachs are common in my country and they have chromed cylinders... we have to run it with some sort of cast iron rings... (i learn this in the hard way some years ago)
the same with steel bores. cast iron rings and steel bore don´t mix...

but this bike has a plated cylinder with nickasil (i think) and the chromed rings will run fine, that´s why i think stock or pro-x piston and rings will be ok for a steel sleeve... but i really want to be sure, it is the first time i use a sleeve and don´t want to mess...

fox, your right, i will email them or pro-x... it´s the safest way :cool:

 

[helio lucas]

i still have that cylinder that i run chrome rings in a chrome plated cylinder...

 

[whenfoxforks-ruled]

I would have sworn that I bent a ring or 2 back in the day, or they snapped. And, I thought they were iron rings, 75 CR125 Honda. And this is the real fuzzy part was the cylinder bore, STEEL? And now they have how many different types of bore materials, 5 or 6, yesterday I seen an aluminum bore in a lawnmower engine! I hope I remember to see what kind of rings were in it. Now that was a throw away block! Wiseco's website states the difference. But, I do not know how the Portuguese translation would turn be.

 

[dans9717]

I replaced my 89 RM250's top end in 07 with a standard Wiseco piston and a set of molybdenum rings. I have an aftermarket steel sleeve and I have had no problems what so ever. The power valves will have to be ground to insert the sleeve, but I haven't noticed any power loss. I had a local shop do my machine work and I assembled it myself. I'm still using the same top end and the bike runs perfect! I ride desert trails and single track in 100+ degree temps full out and have not experienced any engine problems yet. I probably have around 150 hours on that rebuild. My suggestion is to have a new sleeve installed and throw in a Wiseco piston with some molybdenum rings. As long as you find a shop that does really good machine work you'll be alright. ;)