6 Common Issues With Harley's Twin Cam Engine

Good and Bad

Harley-Davidson has churned out its fair share of powerplants over its century-plus in existence, and as it typically the case, some of those engines are better than others. The Twin Cam powerplant, for example, experienced its fair share of problems early on, though that isn't necessarily a good reason to shy away from motorcycles powered by it. Regardless, if you're in the market for a Twin Cam-powered Harley, here are some common issues you should be aware of, straight from the folks at S&S Cycle.

Photos: Harley-Davidson

Cam Chain Tensioners

First up, we have the cam chain tensioners, which tend to plague the Twin Cam 88, specifically. Early models utilized plastic tensioners, which wore prematurely and led to shavings entering the oil pump. As one might imagine, this can result in total engine failure and can do so without any kind of warning, which isn't ideal, to say the least. 

Photos: Harley-Davidson

Oil Leaks

While many Harley engines are notorious for leaking oil, the Twin Cam 88 is worst than most. The most common areas for leaks tend to happen near the base and rocker box gaskets and can lead to seepage problems in a variety of components - including the engine itself. 

Photos: Harley-Davidson

Crankshaft Runout

Excessive crankshaft runout is a bit less common in the Twin Cam engines, though more prevalent in Stage 2 and 3 upgraded versions. This issue can cause a variety of problems such as increased vibration, noise, and premature wear for various components, which is why owners should measure runout before slapping a bigger cam in their Twin Cam powerplant.

Photos: Harley-Davidson

Transmission Issues

In some cases, Twin Cam 88 owners have had issues with the transmission making clunking noises, trouble shifting gears, or even finding neutral. Trouble is, that these problems can also lead to premature and excessive transmission wear, which isn't ideal, either. 

Photos: Harley-Davidson

Stator Failure

Stator failure is also quite common among Twin Cam owners, which can be caused by charging system issues. This can cause the battery to drain, along with difficulties starting the bike, and is one of a few electrical issues that seems to plague this powerplant. 

Photos: Harley-Davidson

Engine Heat

Finally, some owners have reported having issues with their Twin Cam engines generating excessive heat, which is especially true when their motorcycle has been sitting in traffic or idling for a long time. This problem became less prevalent later on thanks to cooling system improvements, and owners can also look to the aftermarket for upgraded oil coolers to help resolve it, too. 

Photos: Harley-Davidson

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