Cylinder re-coat versus sleeve

[jakeslouw]

L.A. Sleeve offers a replacement CrMo replacement sleeve for the KDX200.

https://www.lasleeve.com/cylinder-sleev ... eve-ka5252

I can buy a sleeve and new piston/ring kit for less than half of the price of just an imported remanufactured cylinder...........IF I could find stock of said cylinder anywhere. They usually go for around USD$500 which excludes shipping.

Considering that finding a competent cylinder refurb shop in my country that can recondition the alloy cylinder and recoat to factory tolerances, is like finding a unicorn, what are the downsides of a Chrome alloy sleeve?

[SS109]

Problems are that the sleeve will need honing/boring at piston changes, tend to retain more heat, port alignment issues are common, and the sleeve can actually move in the cylinder if the press fit tolerance isn't correct and/or if the sees extreme temperatures. If you are going to do a sleeve then make sure to use a shop that has lots of experience installing them and that will at least reduce your risks.

It might be worth shipping your existing cylinder out of country to a place in Europe or the US to get it replated.

[kdxdazz]

i have 2 kdx220's and just got them both sleeved, workmanship here in australia at serco was excellent ,ports lined up perfectly,i'll try post a photo for you when i get home from work, they used the la sleeve,
the problem with asking the question about sleeve vs nikasil is everybody who gets their cylinder re nikasiled will say avoid sleeves and everybody that gets a sleeve says no problems at all, i'm in the same boat as you, nobody in thailand does recoating, there is nothing wrong with sleeves at all, they do have some disadvantages compared to nikasil but they also have some advantages hence the reason i chose sleeves

[jakeslouw]

@SS109: yeah, I hear what you are saying. To ship a cylinder from here to the US or europe, with the cost of the work, would be the same price as buying a low hour WR250F over here.

@kdxdazz: Thanks for that. Having a cylinder milled out and press-fitting a sleeve here is do-able. Then boring it out to the piston size is a service that I can also get access to. Lots more engineering shops here that can do that than Nikasil experts.

Just an update: got pricing from a bunch around 100kms away that are willing to do Nikasil..........for just under USD$400, excluding VAT and shipping.
So we're back to USD$500 without a piston kit.

[Slick_Nick]

I've run a sleeved cylinder for years. It's nice because I can actually hone it when it's time for a top end. Never had an issue.

[jakeslouw]

I've run a sleeved cylinder for years. It's nice because I can actually hone it when it's time for a top end. Never had an issue.

Where is the THANKS button on this forum?

[kdxdazz]

this is the la sleeve

[Chuck78]

****IMPORTANT TO NOTE
Generally, technicaly speaking, you need to discard the piston rings that come with any KDX piston if you run a sleeved cylinder, as all of these pistons come equipped with rings intended for plated cylinders. Cast iron or steel sleeves will require a different piston ring composition to the best of my knowledge, otherwise you won't get the best wear out of the cylinder.
Consult the piston manufacturers for the most correct answer.

[Chuck78]

Also, Nikasil cylinders don't require honing, only de-glazing with a scotch brite type abrasive pad by hand.
Another often overlooked fact is that you should always drain your fiel tank and mix up a gallon of low cost mineral oil pre-mix on new piston rings, for proper break-in. This has been proven by Polaris on a dyno that it yoelds significantly more power than using your normal modern synthetic oil for break-in on plated cylinder piston rings.
The cross hatching pattern is still viaible plenty on Nikasil plated cylinders long after new. On the original electrofusion plating from the 1990's Kawasaki factories, not so much vs the superior Nikasil.

Sleeves work, but are always a downgrade in quality, reliability/longevity, and heat transfer especially in slow technical hard enduro type riding. If you do this type of riding, you should go to great lengths to get a Nickel Silicon Carbide plating job done. They will nearly last the lifetime of the bike and rider.

[kdxdazz]

****IMPORTANT TO NOTE
Generally, technicaly speaking, you need to discard the piston rings that come with any KDX piston if you run a sleeved cylinder, as all of these pistons come equipped with rings intended for plated cylinders. Cast iron or steel sleeves will require a different piston ring composition to the best of my knowledge, otherwise you won't get the best wear out of the cylinder.
Consult the piston manufacturers for the most correct answer.

are you able to provide evidence that the OEM kdx piston rings won't work on the LA sleeve? i'm not aware of any such information and as you know kdxrider is a minefield of misinformation, look at the recent jetting thread where somebody posted completely false needle specs
i'm just completeing a bare frame restoration on my kdx220sr and will be using OEM rings on my LA sleeve, the reputable company that installed the sleeves never mentioned anything about kdx rings not being compatable

[Chuck78]

****IMPORTANT TO NOTE
Generally, technicaly speaking, you need to discard the piston rings that come with any KDX piston if you run a sleeved cylinder, as all of these pistons come equipped with rings intended for plated cylinders. Cast iron or steel sleeves will require a different piston ring composition to the best of my knowledge, otherwise you won't get the best wear out of the cylinder.
Consult the piston manufacturers for the most correct answer.

are you able to provide evidence that the OEM kdx piston rings won't work on the LA sleeve? i'm not aware of any such information and as you know kdxrider is a minefield of misinformation, look at the recent jetting thread where somebody posted completely false needle specs
i'm just completeing a bare frame restoration on my kdx220sr and will be using OEM rings on my LA sleeve, the reputable company that installed the sleeves never mentioned anything about kdx rings not being compatable

KDX Rider is a valuable source of detailed information, but the internet as a whole is a source of lots of opinionated misinformation.

I do, however, stand corrected. Checking with the piston manufacturer as I did suggest, Wiseco says their rings for a Nickel Silicon plated cylinder will work for a chromoly sleeve, although some internet forum experiences will tell you that perhaps they don't play as well with a sleeve as they do their intended bore surface finish. Wiseco says the only big NO is for chromed cylinders.