Honing a Shihl Cylinder. What's the proper grit?

[Brian VT]

Sounds like you've got nothing to loose by trying it on that cylinder.
Post some pics of before and after.

 

[shorthunter]

I am in agreement with Brad on this topic. Nothing wrong with a light hone on a chrome or nicasil cylinder.

I do things a little different than most though. I use a 240 grit flex hone that is properly sized to the cylinder (slightly larger). I then submerged the cylinder half way into soapy water. This keeps the hone clean and eliminates any metal buildup in the ports. 3-4 strokes with the hone is normally all it takes to clean up the cylinder.

I really think that honing is more dangerous on a cylinder that is in poor condition than it is on cylinders that are in good condition. I have only damaged one cylinder with a hone and that cylinder was junk to begin with. It had chrome flakes coming off before starting with the hone, as you can imagine the hone enlarged the damaged area by removing more chrome.

The fine grit ball hones that Baileys sells are VERY handy when trying to save a cylinder. I remove the transfer with acid and wet/dry sandpaper by hand. But there are always scratches left over. The hone does a very nice job of finishing it out. I might add that it takes a LOT more to go through the NiSi than many of you seem to think. I've not done it yet. My process is to submerge the cylinder and hone in my parts washer filled with mineral spirits.

Now, with that said, I do not recommend honing a good cylinder when replacing the rings. On the other hand, I know some guys that port finish every job with a quick hone. It may not be necessary, but I don't think it's near as bad as many of you are making out. JMHO

 

[banana boat]

 

[RTK]

Bingo, we have a winner. I was told this many years ago and have used the scotch brite pads ever since.

 

[shorthunter]

My Moto-X engine builders have been honing nikasil cylinders for years and they turn out really good work. I have put hundreds of hours on honed cylinders and never ran into issues. Nikasil and chrome are very hard, you would have to be really careless to actually wear through the finish with a hone. Anybody know who the guy is in the YouTube video?

 

[RTK]

You can but there is no need to try and hone nikasil, more damage than good can come out of it.

 

[shorthunter]

[quote"RTK, post: 4760148, member: 43402"]You can but there is no need to try and hone nikasil, more damage than good can come out of it.[/quote]

I dont buy it. Top AMA MX mechanics wouldn't hone cylinders if it would damage them.

 

[old-cat]

http://www.sunnen.com/graphics/assets/documents/2b6bcac2b33a.pdf
Here's some very interesting reading about honing Nikasil

 

[Jacob J.]

http://www.sunnen.com/graphics/assets/documents/2b6bcac2b33a.pdf
Here's some very interesting reading about honing Nikasil

What that PDF is describing is the "final sizing" of the cylinder after the plating. It is not describing the honing of a working cylinder that's already been in service.

 

[banana boat]

[quote"RTK, post: 4760148, member: 43402"]You can but there is no need to try and hone nikasil, more damage than good can come out of it.

I dont buy it. Top AMA MX mechanics wouldn't hone cylinders if it would damage them.[/quote]





haha like a Top mx mechanic would reuse anything, they would replace it with a brand new cylinder just like every other part on those bikes gets replaced after a few races......hone your funny

I Have had quite a few 2 stroke cylinders ported by some of the biggest names in motocross not one has ever come back looking like it just got honed unless i Was having the cylinder replated at the time of porting.

 

[shorthunter]

Banana boat, you are correct when it comes to the actual race bike. The top pro mechanics use all new components. The reason that they have new components on race bikes is that a race bike starts out brand new, 3-4 motos and it is replaced with another new bike. That bike is then sold or demoted to a practice bike.

They put over 100 hours on their practice bikes each year. Piston & rings are replaced every 15-20 hours on the practice bike.

Done arguing, just wanted to make my point.

 

[Ax-man]

Wish I had read this thread before ordering two hones( 320 grit) from bailey's for an upcoming 066 used cylinder project. The saw has a history of spitting plugs and the plug hole is shot. I got a hold of some parts saws that have good looking jugs. I thought I was on the right track by ordering the hones so I could do a real good job getting this saw back to work. Looks like I might have wasted some money by some of the replies in this thread.

I have always gone the sandpaper and ScotchBrite route in the past when redoing cylinders but this is getting old to me and thought a hone would speed things up and improve the looks of the cylinder before putting it back on. My plan was to sandpaper the cylinder first, getting the rough stuff done, then hone it for a final finish. That NiSil is tough stuff and I honestly think a hone used conservatively wouldn't harm the lining. I have used flapwheels in the past with no harmful effects.

How about this idea. Get rid of the drill and just use some kind of T handle on the end of the hone. To me this is more like hand sanding but your covering more area inside the cylinder. I have honed 4 stroke engines but never a chainsaw cylinder. I really don't want to cancel the order I just placed because I always thought I could use a hone and this 066 cylinder project is important enough to spend some money on a hone to finish the replacement cylinder. I like Brad's reply to this thread. A hone is just another tool. Any more thoughts.

P.S I guess I could hone the junk cylinder to see what happens which is what I'll end op doing just to see for myself and draw my own conclusions.

 

[xxl]

When i put a new piston and rings in my 660 i did not hone it. I just used sand paper to clean off aluminum transfer that was it. Only used about 400 grit. Put new piston and rings in it. Runs very well How well you ask just ask that 3 foot diameter sycamore it took care of big time.

 

[old-cat]

Think of it this way, Nikasil is HARD like a file. Rings are iron (soft). Do you want to run soft metal against rough metal, like a file?
New rings are not smooth, the rough edge rubs against the smooth Nikasil and conforms to the cylinder, making a seal.

Most 4 cycle engine cylinders are iron (soft) so the cylinder and rings conform together. Honing speeds up that process.