Liquid Cooled HD

It has been 2 years since Harley-Davidson announced that several bikes in their 2014 lineup will feature liquid-cooled cylinder heads for the first time in their 111 years history. But what does liquid cooling really mean for the rider and for the Motor Company?
Here’s the lowdown, first some people might assume that the term “liquid-cooled” refers to a full-blown, water-cooled engine, but Harley’s Twin-Cooled power plants use both oil and water for cooling, applying coolant only to the cylinder heads (which leaves the engine block cooled by oil and air), and focuses the cooling effort towards the hottest part of the heads: the exhaust valves.
Next you may have heard that Harley has boosted engine output between 5 and 7 percent, which might make you think those gains are all due to liquid-cooled heads. But that’s not entirely accurate.

liquid cooled

The engine improvements which came with Project Rushmore include new cam profiles with higher lift and duration, which aids overall performance. But both the standard and Twin-Cooled engines see the performance gains. The main advantage is the Twin-Cooled engine is considerably more comfortable thanks to its liquid-cooled heads, but other parts of the engine still managed to heat up your legs and lower thighs.
Contrary to popular belief, Harley-Davidson didn’t have to go with liquid-cooled heads because of regulatory constraints or government certification requirements. The system was designed based on customer feedback, and Harley left the door open to either expand it throughout the lineup, or eliminate it if customers revolt.
But based on initial public reaction, it looks like Harley’s Twin-Cooling system is here to stay, and probable expand throughout their lineup of bikes.

Trivia Question of the Month:

Question: What classic logo did Harley-Davidson use for the first time in 1908 and didn’t have trademarked until 1910?

Answer to last month’s trivia question:
Question: Popular belief is the 88B twin cam motor released in 2000 was Harley’s first twin cam motor, this is actually not correct. What year and model featured the first twin cam motor by Harley-Davidson? Good luck!

Answer: In 1928 the model JH was a variant of the popular JD model with a 61ci. twin cam motor known then as the “two-cam.” The J series was replaced by the D series in 1930.

Bo’s Monthly Words of Wisdom:
The definition of “Junk motorcycle parts” are something you’ve kept for years and throw away two weeks before you need them.
“Live to Ride or Step Aside”
Written by Bo
“The Hog Shoppe”

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