I've spent the past 22 years as a professional in the HD Motorcycle industry, I started at the end of the Evo/Beginning of the Twincam eras, Road Kings & Fatboys were everywhere and Road Glide owners were looked at like BMW owners... Times have Changed!

Coming from the Automotive Industry, I felt like I stepped backwards twenty years. Carburetors were still stock, entertainmanet was terrible, and those new Computer Thingys were starting to show up. That being said, the engineers have made great strides in a relatively short period of time, In my opinion the technology in todays models are relative, and the M8 is hands-down the best Powerplant they've built. Unfortunately, like everything else in the world, it has some inherent flaws.


HD motors (like most Internal Combustion Engines) operate using a Dry-Sump System, the reciprocating parts are lubricated by direct and Splash lubrication while maintaining the balance of the oil in the oil pan. The Internal rotating components are not intended to be operated in standing oil, this creates drag on parts and will affect performance, heat, possible component failure. 

Big Twin Motors use a Two-Part Oil Pump, one is to create oil pressure and the other is to Scavenge oil from the crankcase. The early M8 Oil pumps were designed with a flaw that created more pressure than scavenge, in scenarios of Hot Temperatures, excessive high RPM riding, or thin oiil viscosity, the engine will "Sump". Sumping is when the engine is not able to effectively remove the oil from the Crankcase, this creates pressure which in turn pushes oil out places it wasn't intended to (Out your Air Filter, down the side of your bike, all over your Passengers Fancy HD Jeans that cost $$$$$).

Luckily there's an easy solution for this one, replace the oil pump. Updated (2020 & Newer) OEM pumps and most After-Market pumps resolve this situation, if you own one of these models and intend on replacing your camshaft, it's a great time to address the issue. If you're on a long ride and feel like your bike is losing power, there's a good chance this is your issue.


Rings... (I'm not talking about your Skull/Bar&Shield/FTW ones)

Cylinder Ring to Cylinder seal is critical for a proper operating engine, unfortunately somiething is amiss at the Factory, we see a significant number of stock M8's with poor seal. There are some theories floating around as to why this is occurring, that's not our job, our job is to find an effective solution to the problem. We've found that Aftermarket Cylinders with High-Quality pistons is the solution! We inspect all our kits to verify proper fitment, we cut rings for proper end-gap based on the application, our in-house engine builds are Broken in on our Dyno in a controlled environment so that we can monitor data and have the best opportunity for longevity. 

By Creating a Proper engine seal we're able to eliminate the chance of excessive Crankcase pressure, this reduces the likelihood for the breather system to get overloaded, a lot less chance of having to replace those $$$$ Jeans.


There's a lot of products floating around intended to cure this issue, I'm sure most had best intentions, but in our opinion, they won't fix the root cause. If you notice excessive oil consumption, oil leaking outside of the air cleaner or a strong scent of burning oil from your exhaust, there's a good chance you may be experiencing one (or both) of these issues. With relatively easy inspections we can determine if you have a problem, make good recommendations for your riding style and expectations. 

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