Siebenrock Powerkit Cylinders & Piston rings.

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boxertwinjeff
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Siebenrock Powerkit Cylinders & Piston rings.

Post by boxertwinjeff »

Are these Cylinders made of Alloy?, so no corrosion, and are the Piston rings made from Stainless?
Also, will the Nikasil coating help to resist any scouring or damage to the surface if moisture is present?
1973 R1000/5 LWB
1976 R90S Silver Smoke
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mattcfish
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by mattcfish »

boxertwinjeff wrote:Are these Cylinders made of Alloy?, so no corrosion, and are the Piston rings made from Stainless?
Also, will the Nikasil coating help to resist any scouring or damage to the surface if moisture is present?
Yes, high quality, lightweight and strong aluminum alloy pistons. The Nikasil coating is the best you can get for an airhead.
They resist just about everything, are lighter, and cool much more efficiently. The expansion rate is very near the same as the pistons so higher tolerances can be used. Not sure what the rings are made of but they are selected to work with Nikasil.
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
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vanzen
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by vanzen »

The cylinder casting will certainly be an alloy.
Nikasil, introduced by Mahle in 1967, will be a brand name
and essentially what is generically known as a "chrome-bore" –
An electrodeposited lipophilic nickel matrix silicon carbide coating
applied to the machined interior surface where the piston resides.

Common thought says that most normal piston ring materials work well with nikasil-type bores,
but I have been one to only use those rings as prescribed by BMW for their Nik cyls.

Nik bores are known to last, but if they should wear, chip, peel, barrel, or go out of round –
The old Nik must be removed, casting machined/repaired, new plating applied ... a costly process.
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boxertwinjeff
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by boxertwinjeff »

With Siebenrock's Piston rings being of a very high quality, could you thus say they would be
less prone, and more resistant to Corrosion from adverse climatic conditions
( moisture from High humidity) in a bike sitting for say 3 months?
1973 R1000/5 LWB
1976 R90S Silver Smoke
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SteveD
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by SteveD »

With the Euro misbehaving, it sure is a good time to buy the Siebenrock goodies.
Cheers, Steve
Victoria, S.E.Oz.


1982 R100RSR100RS supergallery. https://boxerboy81.smugmug.com/R100RS
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1994 R1100GS.
Major Softie
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by Major Softie »

boxertwinjeff wrote:With Siebenrock's Piston rings being of a very high quality, could you thus say they would be
less prone, and more resistant to Corrosion from adverse climatic conditions
( moisture from High humidity) in a bike sitting for say 3 months?
No.

Nikasil cylinders are specced to run with cast iron rings, so, as far as I know, It doesn't matter what the quality, you either end up with an iron bore or an iron ring, and neither one is "resistant to corrosion."
MS - out
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mattcfish
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by mattcfish »

boxertwinjeff wrote:With Siebenrock's Piston rings being of a very high quality, could you thus say they would be
less prone, and more resistant to Corrosion from adverse climatic conditions
( moisture from High humidity) in a bike sitting for say 3 months?
Your rings won't rust in 3 months if the bike has at least been run once. ...unless you are planning to store the engine underwater (or sitting out in the elements with the intake tract open). I opened my friends bike up after 11 years in Pacific Northwest dampness. No corrosion inside at all (iron bores) . The outside of the motor was covered with white aluminum powder.
Bellingham, WA USA
1975 BMW R90/6
1975 BMW 2002
1971 VW Westfalia
1985 VW Vanagon
http://advrider.com/index.php?threads/b ... s.1074183/
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boxertwinjeff
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Re: Siebenrock Powerkit Cylinders & Piston rings.

Post by boxertwinjeff »

Wolfys been sitting in my loungeroom for 4 months now, had a friend put a few drops of engine oil
in the spark plug holes then turn the rear wheel by hand in top gear a few times.
I've just found this product made by Sta-bil, Engine fogging oil which I'm sending him
to spray on the Cylinders, wish I'd known it existed earlier. Is this the best product
for a laid up bike?, and should he turn over engine by hand once sprayed in the spark plug holes?
1973 R1000/5 LWB
1976 R90S Silver Smoke
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