Hone Nikasil cylinders?

[montmil]

I currently have three Airheads. The '81 R65 is getting new iron piston rings and freshened cylinder heads. A local indie motorcycle shop, operated by a grey-beard Butler & Smith service school graduate, is inspecting the new-to-me cylinder heads and will IRAN the pair.

As to the cylinders, the gentleman suggests a very light hone -with heavy emphasis on the light- then a wash out with a solution of laundry detergent such as Tide. Here's where I'm really looking for some feedback:

After wash and a rinse (this is beginning to sound like a hair salon rather than a machine shop) allow the jugs to sit for a couple hours until a light tan/brown oxidation appears. Then wipe the bores with a lightly oiled towel. A thin wisp of oil on the piston skirts and reassemble. This method is reputed to aid in ring seating and less unwanted exhaust smoke... which I already had.

I've read Oak's Top End Manual and quite a few posts on different forums regarding Nikasil cylinders, but this is the first suggestion I've heard/read about the Tide Treatment. Comments from the Council of Elders would be most appreciated.

Monte Miller
Denton, Texas, y'all

[enigmaT120]

I just follow Oak's manual. I've had two sets of rings in my R65 and still have the original hone marks. Both sets seated basically instantly, with the first minute of running the motor. No smoke, no oil usage. The second time the bike had somewhere around 85,000 miles and the original hone was still enough to do the job.

[Duane Ausherman]

That wash and rust advice was for iron cylinders, not the Nikasil as I remember. It was made by Butler and Smith to solve the problem of the /6 not seeming to seat rings. The real problem was the rear main seal.

What is the proper amount of rust in your engine? How many manufacturers recommend putting rust in your engine? How many times in your life have you put rust into some engine?

Are you getting the picture? I think that you asked because it didn't sound right. Good for you. This whole subject died out decades ago.

[montmil]

I thought something sounded not quite right about the Tide Treatment. As Duane mentioned, adding rust to an engine, "does not compute".

Back to the honing question- The bores on the '81 R65 show no hone marks at all. Might a light, diagonal swipe with something like 400 wet/dry be beneficial? I have a few small, soft rubber sanding blocks left over from an automotive paint project that might aid in dressing a curved surface.

One down n' one to go! Thanks.

Monte

[Kurt in S.A.]

There is a special type of hone (ie, special material) to use with Nikasil walls. And there are also special rings (IIRC) that go with Nikasil...I don't think you use iron cylinder rings. Could be wrong...

Kurt in S.A.

[SteveD]

There is a special type of hone (ie, special material) to use with Nikasil walls. And there are also special rings (IIRC) that go with Nikasil...I don't think you use iron cylinder rings. Could be wrong...
Kurt in S.A.

That's right Kurt. The pn's for the earlier rings for the R65 are different. Nikasil from 10/79 according to the fiche.

RealOEM--

REPAIR KIT PISTON RINGS D=82 ? 10/1979 11251337401 $72.28

MaxBMW--

11 25 1 337 401 SET: REPAIR KIT PISTON RINGS - D=82 (from 10/79) 0.08 X $66.91
One set has a set of three rings in it. Applies to Nikasil cylinders.

[PAS]

Iron cylinders use chrome rings, Nickasil cylinders use cast iron rings. I used Goetze rings from Motobins years ago in my 81 R100RT jugs. They are the OEM mfg'r
Bike has 164K and doesnt burn oil.

[montmil]

Thank you, PAS. As the Nikasil coating is harder than my younger son's head, chrome rings will likely never seat well to the walls; hence the use of iron rings that will break-in and conform to the Nikasil bores. Non-Nikasil bores do utilize the chrome rings and the bore breaks-in to conform.

Aluminum Oxide stones and/or bore brushes are used, gently, on the Nikasil bores to re-establish a close to 45-degree angle cross-hatch pattern. The bores on my Airhead in question show no sign of the OEM cross-hatch pattern so will benefit from a light hone.

Monte Miller

[montmil]

Quick follow-up regarding the Nikasil cylinders:

Further research with several hours spent bouncing between different sections on the Snowbum's site -Thanks, Bob- turned up this little gem. Das Bum suggested using a green 3M Scotchbrite pad along with hot, soapy water to break/remove any glaze on the Nikasil bores.

A tub of hot water, some Dawn liquid dishwashing detergent -if it's good enough for oily sea birds, it's good enough for my cylinders- and a closer look from my tired, old eyes revealed... OEM hone marks.

I'll get this top end project completed pretty soon but I'm still a bit hampered by a finger that lost a first-round bout with a carbide tablesaw blade. The orthopedic surgeon told me, "Your days as a fashion photographer's hand model are over."

Monte

[Ken in Oklahoma]

. . . I'll get this top end project completed pretty soon but I'm still a bit hampered by a finger that lost a first-round bout with a carbide tablesaw blade. The orthopedic surgeon told me, "Your days as a fashion photographer's hand model are over."

That's funny. I hope I never have an opportunity to use that line myself. (Note to self: Even though you pay attention to safety in the shop, pay more.)

Ken