Cylinder Rebore, Replating and Repair.

US Chrome

Extreme Engines Limited under take all kinds of cylinder plating, cylinder honing, cylinder repair and cylinder reboring work for 2 stroke single cylinder and 4 stroke monoblock motorcycle cylinders.

We are the UK dealer for the American Company U S Chrome. Who has been in the plating business since 1946 and since that time they have plated over 1.000.000 cylinder bores.

No other cylinder repair company can compare with their experience, technical depth and business integrity. With over 11,000 satisfied customers, engineers, power-sports racers and riders worldwide in our active customer network, it is easy to see why the other cylinder re-plating shops try to imitate but can never duplicate the U.S. Chrome business and technology models.


Technical Data

Electroplated composites consist of a plated metal matrix with one or more other materials uniformly dispersed throughout it. These coatings are applied in a single plating bath and any material that can be plated with other metals can be plated with composites.

Honda CR125
Composites combine the properties of two or more separate materials synergistically to produce new materials with properties superior to any of the components. A familiar example is concrete which is a composite of Portland cement, sand and gravel.
Our electrodeposited composites are principally nickel and silicon carbide in which the nickel is the matrix analogous to the Portland cement in concrete while the silicon carbide can be compared to the sand and gravel. With any of our composites a very small amount of a laminar lubricant such as boron nitride or graphite can be added to improve the frictional properties.

Occasionally technical people will express concern over the fact that silicon carbide is also an abrasive. An extremely hard material, its function is to greatly increase the wear resistance of the coating. IT IS ABSOLUTELY NOT ABRASIVE in our composites because of its minute particle size which averages three microns.

All surface finishes possible with other metals and ceramics are possible with these composites.


Honda CR250
In sliding wear applications, under a wide range of loads, U.S. Chrome's NiCom wears up to ten times the same thickness of chromium. This is its most outstanding property, but it also has good frictional characteristics, in part due to its superior wettability compared with chromium or electroless nickel. It is very easy to maintain hydrodynamic lubrication conditions because of the oleophyllic nature of the coating. This accounts for its very extensive use abroad in internal combustion engine cylinders and hydraulic equipment. Additionally, it has excellent corrosion resistance and its upper operating temperature is greater than chromium or electroless nickel. Prolonged exposure to 1200 F (540 C) does not result in significant loss of its physical properties.

Our unique honing process uses a double diamond plateau technique that symmetrically sizes the bore. The finished surface allows for superior oil retention due to the oleophyllic nature of the silicon carbide in the NiCom coating. The repaired part is then thoroughly inspected before being returned to the customer.


Yamaha YZ125
U.S. Chrome has more than twenty years of experience with Nickel-Carbide composites. Our principal contribution lies in our proprietary technology that enables us to apply the coating as easily as ordinary nickel plating using standard equipment to produce thicknesses up to 0.025". As a practical matter, electroless nickel composites are limited to coatings of 0.001" (25.4microns) or less.

Nicom Nickel Silicon Carbide Dispersion Coating

NiCom is an electro-composite coating consisting of a nickel metal matrix with hard particulate dispersed uniformly within it. The process involves electroplating nickel in the presence of hard particulates, such as SiC, under conditions allowing the hard particulate to co-deposit with the nickel. The result is an electroplated composite material where engineering thickness can be achieved for both original equipment manufacturing (OEM) or overhaul and repair (O&R).

Electro-composite materials, such as NiCom, are viable alternatives to Hard Chromium Plating due to their excellent wear resistance. Superior sliding wear characteristics are achieved due to the hard particulates dispersed within the metal matrix. Mating


Features & Benefits

Porsche 911 3.2 litres 1987
1. Excellent sliding wear rear resistance usually 2 to 10 times better than chrome
2. Build-up possible up to 0.030+
3. Superior adhesion to all metals including aluminium and titanium
4. Outstanding corrosion resistance



Race-Proven Increases In Performance/Horsepower

1. Significantly better heat dissipation, heat transfer, and cooling
2. Greater durability and wear resistance compared to conventional steel or cast iron sleeves
3. Wear resistance provides tighter piston-to-wall clearances reducing blow by
4. Piston “ring-drag” reduced
5. Bigger bore-bore displacement possible



NiCom OEM & Repair Applications

1. Snowmobiles & Motorcycles
2. Dirt Bikes, Street Bikes, & Drag Bikes
3. Personal Watercraft & Marine Blocks
4. A TV & Shifter Karts
5. V8 Automotive Mono Blocks
6. Porsche Blocks (911, 944, & 928)


Please call us for further details and pricing by contacting 01354 680164