Lucas Deep Clean Review [Fuel System Cleaner for Motorcycles]

Lucas Oil Products started out with Forrest Lucas developing oil stabilizers and fuel additives in response to problems he saw over his 20 years as a trucker. Lucas Oil Products has been in business since 1989, and it has expanded quite a bit in the intervening 33 years. One of the Lucas products I have used regularly over the years in both my cars and motorcycles—and yard/garden equipment, for that matter—is Deep Clean, which the Corona, Calif.-based company bills as “A Real Fuel System Cleaner.”

Lucas Deep Clean Review Bottles
Lucas Deep Clean comes in sizes ranging from 5.25-ounce bottles to a 55-gallon drum.

The effectiveness of many petroleum products tends to be best measured in increased equipment performance and/or reduced wear over time. In the case of Lucas Deep Clean, I have relevant long-term, in-use experience.

Among my 13 motorcycles, ranging in vintage from 1973 to 2015, with carburetors and points ignition systems to electronic ignitions with EFI, I own a 1981 Yamaha Seca 750 inline-4 and a 1985 Honda Shadow 500 V-twin. Both have carburetors and tend to get a lot of downtime over the long upper Midwest winters. That can lead to problems with fuel system varnish build-up, hard starting, and poor performance, even with non-ethanol premium fuel in the tanks. Add the challenge of cold-weather starting, and you have the recipe for some frustrating times at that first spring start-up.

I tend to start my riding season when air temps are in the 40s and snow still on the ground—conditions that can make 40-year-old bikes reluctant to fire up. The Seca and Shadow are two particularly good examples to focus on. They are kept in the far north, get ridden least often, and sit through the longest period of winter conditions fully fueled up. Neither of these bikes has ever had the carburetors replaced, rebuilt, or even given an off-the-bike cleaning. Yet, this spring, as in years past, despite cold (temps hovering in the 40s) conditions and snow still on the ground, both old street bike motors fired right up and ran like new. How is that possible?

Yamaha Sea 750 and Honda Shadow 500
With snow still on the ground, air temps in the 40s F, and after sitting unused for long winter months, the first start-up of spring could be a problem for my 1981 Yamaha XJ750RH Seca and 1985 Honda VT500 Shadow if those old carburetors were fouled with varnish and gunk build-up. They both started right up.

Key factors include a Battery Tender in use while in storage to keep the cold-cranking amps up there, routine maintenance, and years of regular use of Lucas Deep Clean. Of course, that’s easy to say in speculation. But what makes me think that it is? For that, I look at what it’s made of.

According to the product’s Safety Data Sheet, it is comprised of medium aliphatic petroleum naphtha solvent (30-60 percent) and polyether amine (10-30 percent). No other chemical components are reported because they are not considered hazardous in the concentrations present in the product.

Petroleum naphtha is used as a solvent in a variety of cleaning agents. It has a low evaporation point, making it useful as a diluter for paints, asphalt, and varnish. It burns clean, so it leaves virtually no residue of its own. As a result, it can dissolve that dark, gunky varnish that tends to build up over time in the pre-combustion parts of fuel systems, from the fuel tank to the intake valves. That is particularly important for old bikes, bikes that tend to sit with fuel in them for extended periods or both. Petroleum naphtha works, whether de-gunking the jets and fuel circuits in a carburetor, or nozzles in a fuel injector.

The polyether amine component is useful in cleaning the engine’s combustion chamber, piston, and valvetrain parts. Amine molecules in the fuel stream attach to carbon deposits that build up from the combustion of hydrocarbons in the fuel. It softens the deposits, which allows the carbon to gradually be shed from the internal surfaces of the engine and into the exhaust stream.

Lucas Oil Products claims the removal of carbon deposits eliminates pre-ignition pinging or spark-knock the residues can cause, reduces tailpipe emissions, and improves performance and fuel efficiency. Judging from the product’s chemistry, it makes sense that Lucas Deep Clean fuel system cleaner can actually do those things. However, from my point of view, there’s one more thing it can do—it helps get my bikes going, be they old or new, even in less-than-ideal start-up conditions.