Suzuki cylinders...to hone or not to hone

[los36]

OK, I've got an 02 RM 250 and I'm about to do it's second top-end. I'm thinking that the cylinder will probably need some sort of attention this time. I've done a search on "SUZUKI CYLINDER PLATING", "SUZUKI CYLINDER HONING" and on "CYLINDER HONING" and have found no definitive answer.

The manual says NO, but it sounds like it's OK. Eric-can you say YES or NO? When making the decision, assume that I would have a mechanic do the job.

Thanks!!

 

[marcusgunby]

the only one eric doesnt recommend is the KX cylinders.KTM cylinders are the opposite to KXs, the KTM plating is hardly touched by honing.

 

[WoodsRider]

I always de-glaze my cylinder with a "ball hone" when installing new rings. This isn't true honing, but it does provide additional cross hatch for oil retention and seating the new rings to the cylinder. Luckily I have have access to precision measuring equipment. I'll replace the piston and/or have the cylinder honed to the next size (using a true cylinder hone) when they are worn. Also inspect for signs of unusual wear such as scuffing on the piston skirt or plating exfoliation on the cylinder.

 

[Peer Lovell]

A safe way to do this is to use a 3M Scotchbrite pad. Clean the barrel until all the glaze is gone and the hatch marks are visible.

 

[placelast]

In Eric's book he tells you how to do it; 2-3 quick passes with a specific-grade ball hone - yes, on modern plated cylinders.

 

[Jasle]

I think it says use a 240 grit ball hone that is 10% smaller than your bore. I'm only 90% confident it says that as I'm at work and don't have the bood with me.

 

[placelast]

The grit sounds correct but the sizing isn't - it's ~20% larger or so, not smaller. by all means read the book B 4 U buy.

 

[Rich Rohrich]

Originally posted by placelast
The grit sounds correct but the sizing isn't - it's ~20% larger or so, not smaller.

No it's not :silly:

Here are Eric's EXACT words:

All of the Japanese motorcycle manufacturers caution against using any type of hone in a plated cylinder. Its not that its an impossible task, its just because it’s a difficult thing to do correctly. Here are some basic rules for honing light scratches, burnt oil, and minor aluminum scuffs on nickel-plated cylinders. 1) Use a ball-hone with a diameter that is 10% smaller than the cylinder bore size, 240-360 grit, and made of aluminum-oxide material. 2) Never ever use a three-shoe stone hone because they will chip the port edges. 3) Coat the cylinder and ball-hone in oil before honing the cylinder. 4) Chuck the ball-hone in a drill and put the hone in the cylinder completely before turning. 5) Run the drill at a slow speed and stroke the hone back and forth in the bore for about ten strokes. Cylinders that are nickel-plated are very hard (83 Rockwell C Scale) so you can’t remove any metal with a ball-hone. I usually hone a cylinder every time I change the piston assembly. Ball-honing polishes down high spots and sharp port edges without damaging the plating. Ball-honing will insure that the piston and rings have a smooth cross-hatched surface to mate with. Kawasaki cylinders use a different bore material and plating method. The tungsten material is very thin and vulnerable. For those cylinders I suggest using a piece of Scotch-Brite to hand strip the cylinder bore of burnt oil. Whenever you hone a cylinder you should clean the cylinder in mineral spirits solvent and then hot soapy water. Spray the cylinder with penetrating oil to displace the water left over from cleaning.

 

[los36]

thanks all!! :cool:

 

[Chili]

Originally posted by Rich Rohrich
Kawasaki cylinders use a different bore material and plating method. The tungsten material is very thin and vulnerable. For those cylinders I suggest using a piece of Scotch-Brite to hand strip the cylinder bore of burnt oil.

Sorry to hijack your thread los but a quick question in regards to this statement for Rich as I'm about to do the top end on my son's KX 80. Do I need to be careful about how aggressive I am in cleaning the cylinder with a scotch brite pad or is it safe to give it a real good scrub? 1st top end I've ever attempted so I'm trying to get all my questions asked before it's in pieces :)

 

[Rich Rohrich]

The Kawi plating is pretty suspect but you won't hurt it with Scotchbrite pads. I use the #7447 which is a medium aggresive pad. If you do tear up the plating with these pads then you needed a re-plate to start with.

 

[Chili]

Thx Rich!

 

[Peer Lovell]

You can't do any damage with the 3M pad.

 

[placelast]

Here are Eric's EXACT words:...a ball-hone with a diameter that is 10% smaller than the cylinder bore size, 240-360 grit, and made of aluminum-oxide material...

I stand corrected. 10% smaller it is.

 

[Jasle]

Hey and they said my memory would get worse when I got old...Now where was that dany book I can seem to remember where I put it.