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Harley Flathead engine.

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Old Sep 30, 2016 | 09:36 AM
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Default Harley Flathead engine.

I was browsing through the new 2017 Harley brochure and there is a page which shows the engines Harley has used in its bikes over the years.

I noticed the Flathead motor said it was used from 1929 until 1973.

At first I thought that was a misprint....then I checked out information on the internet.

It seems that Harley stopped using this motor in its two wheeled bikes in 1948, and continued using them in the Servicar up until 1973.

I wonder why they didn't change the motor in the Servicar in all those years?

They could have used a Knucklehead, a Panhead, and a Shovelhead in the Servicar up until it was discontinued in the mid 70's.

I am sure with a Shovelhead, someone would have started using those for flat track racing!
 
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Old Sep 30, 2016 | 10:09 AM
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The servicer was mainly used for low speed use by traffic patrol ("meter maids") by then. When I was in college in the early '70's, the campus police still patrolled on a fleet of them.


As such, it didn't need a larger, faster, more modern motor. The tooling for the 45" flathead was long paid for, and the motor itself was a proven design in WWII. The intended customers were also probably not whining year in and year out about "why isn't Harley-Davidson giving us something new and exciting this year?"
 
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Old Sep 30, 2016 | 11:09 AM
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48 saw the last of the large displacement side valve motors. The servicar design (45 cu. in motor) like it's bigger brother side valve motors were a proven design and very easy to work on. And as stated they were sued primarily by police department for meter maid service and as. Such did not need a high top end.
 
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Old Sep 30, 2016 | 12:40 PM
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Servicars did most of their work at idle or very low speed. Running for hours on end in all climate conditions. The OHV engines of the day just wouldn't have stood up to the beating. The Astrodome used Servicars for a long time in their parking lots. I recall wondering at these machines idling from the beginning to the end of games in 100 degree heat. When Servicars were no longer available I heard they tried a trike type machine with a Honda CX water cooled engine. I don't think they lasted very long.

The 45" WL was an excellent machine in peace and war. I rode the one shown from Georgia to Milwaukee for Harley's centennial. A slow trip no doubt, but one I'll always remember.

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Old Sep 30, 2016 | 01:19 PM
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Originally Posted by DaddyKnuck
Servicars did most of their work at idle or very low speed. Running for hours on end in all climate conditions. The OHV engines of the day just wouldn't have stood up to the beating. The Astrodome used Servicars for a long time in their parking lots. I recall wondering at these machines idling from the beginning to the end of games in 100 degree heat. When Servicars were no longer available I heard they tried a trike type machine with a Honda CX water cooled engine. I don't think they lasted very long.

The 45" WL was an excellent machine in peace and war. I rode the one shown from Georgia to Milwaukee for Harley's centennial. A slow trip no doubt, but one I'll always remember.

That is pretty awesome. What would you say the top cruising speed is. How did the bike handle compared to more modern choices?
 
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Old Sep 30, 2016 | 02:09 PM
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There was also an abundance of engines left over from the war, I suspect they used war inventory for years.
 
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Old Sep 30, 2016 | 02:38 PM
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Originally Posted by Kayakguy
That is pretty awesome. What would you say the top cruising speed is. How did the bike handle compared to more modern choices?
Thanks. The guy that built my engine said they were called 45's for a reason. One will run forever at that speed. We had a group cruising the blue highways on the way up. I doubt we ever went much faster than 55. If I was being chased by **** troops I suppose it could do 70-75 for a little while.

The technology is beyond antique. Hill holder front brake. An on-off switch rear brake. Hand shift, foot,clutch, and a spring fork with clamped cork discs for damping. Did I forget to mention manual advance ignition and 6v electrics? Any similarity between that bike and a modern machine is just coincidental.
 
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Old Sep 30, 2016 | 04:20 PM
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I also discovered that fact in the HOG magazine.

I guess that I was just never around an area that used the three wheelers.
 
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Old Sep 30, 2016 | 09:16 PM
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Originally Posted by Kayakguy
That is pretty awesome. What would you say the top cruising speed is. How did the bike handle compared to more modern choices?
If you got one to 60 you had a good tailwind downhill, gave shake rattle & roll a whole new meaning. Far as handling they rode like a brick on 2 wheels. Around town off highways they could be fun particularly if somebody put a reverse tranny in a 2 wheel frame, that was always fun at parties.
 
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Old Oct 1, 2016 | 05:24 AM
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Originally Posted by Kayakguy
That is pretty awesome. What would you say the top cruising speed is. How did the bike handle compared to more modern choices?

I bought a 1963 Servicar from a city auction.
$700 in 1981.
Didn't run, hoses hanging off the gas tank.
As I pushed it to my truck, someone mention "Got a flathead huh?"
I didn't know what it was, other than a "Harley."


Changed rings and gave it a valve job.
It started up on the 1st try.
(My dealer warned me to retard the spark. It would have thown me over the handlebars if I didn't do it.)


Last year for kick-start.
Cool with the 3-speed shifter w/reverse on the tank.


When I got to 50 MPH, that was pretty much the end of any speed.

Dealer said it was geared for chalking tires.
Even had the loop on the box to hold the chalk wand.
More speed was available if I changed out the sprocket.


Sold it because I couldn't carry anybody.
Gas tank hit me in the crotch and the box was against the back of my butt.


$700 to buy plus some parts and valve job.
Sold it in 1982 for $1,700 to a guy 77 years old that didn't look 77.
Said he had one as a kid and wanted another before he died.
Never saw it on the street again.


eBay didn't exist in 1982.
That $1,700 now could probably add another zero to the price.


Made $1,000 and I was happy.
Used the money to buy a 1970 Oldsmobile Cutlass W-31.
116 built in my body style.
Still have the car.
 
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