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What is typical Panhead motor mileagle/life expectancy aprox

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biker_grunt
Posts: 3
Joined: Sun Nov 02, 2008 1:49 pm
Bikes: 60 rigid pan, 71 rigid/springer ironhead, 99 Sporty

What is typical Panhead motor mileagle/life expectancy aprox

#1

Post by biker_grunt » Thu Dec 18, 2008 5:21 am

Guys...

I just scored a clean, panhead period chop/bob w/15k miles on the rebuilt motor.

Can somebody give me a rough "ballpark" idea as to how long a good pan motor rebuild should last in terms of mileage? I have no idea and am trying to gauge when I should expect to have to do major repairs and another rebuild.

ANy knowledgeable input is highly appreciated!!
:?:



biker_grunt
Posts: 3
Joined: Sun Nov 02, 2008 1:49 pm
Bikes: 60 rigid pan, 71 rigid/springer ironhead, 99 Sporty

Re: What is typical Panhead motor mileagle/life expectancy aprox

#2

Post by biker_grunt » Thu Dec 18, 2008 7:35 am

Anybody???

steve_wood
Posts: 947
Joined: Tue Jan 08, 2008 12:32 am
Bikes: 56 FLH, 2007 FLHRCI
Location: Belleville, Ontario, Canada

Re: What is typical Panhead motor mileagle/life expectancy aprox

#3

Post by steve_wood » Thu Dec 18, 2008 12:29 pm

Wow. Tough question. There are so many variables. Who rebuilt the engine? Did they use quality parts? How was the engine broken in? Is it running hot (vacuum leaks)? Any other defects in the engine?

I've heard of rebuilds that fail immediately, or after 500 miles, or 5000 miles. If yours has 15K miles on the rebuild, you've probably got a fairly solid motor. I've also heard of folks with really good engines doing valve jobs every 20K miles - that might be something to think about.

Try a compression check and leak down test. That will tell you the state of your valves, heads and rings. Fairly easy to do and a much better idea than tearing down a running engine.

steve

john HD
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Bikes: '42 WLA X 2, '55FL, '93 Ultra Classic, '91 Fatboy, '97 883, '71 Suzuki Duster 125, '83 GPz 750.

Re: What is typical Panhead motor mileagle/life expectancy aprox

#4

Post by john HD » Thu Dec 18, 2008 12:34 pm

my guess it would depend on a couple of things.

was it rebuilt correctly?

did the oil get changed regularly?

does it have a timken bottom end?

did it pull a sidecar?

did it operate in extremely hot or cold condititions?

does it have a aircleaner? oil filter?

i have about 15K on my last top end, i still have good compression and power. i will probably rebuild the entire motor some time soon, i just figured it is running fine and why bother right now.

i would have to believe a light bike like yours would last longer than a workhorse or a bike pulling a hack if it has been well cared for.

john

Cotten
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Joined: Mon Aug 26, 2002 9:09 am
Location: Central Illinois

Re: What is typical Panhead motor mileagle/life expectancy aprox

#5

Post by Cotten » Thu Dec 18, 2008 2:57 pm

The longevity of any motor is inversely proportional to how loose the nut on the handlebars might be.

....Cotten

panz4ever
Posts: 522
Joined: Fri Aug 12, 2005 5:45 pm

Re: What is typical Panhead motor mileagle/life expectancy aprox

#6

Post by panz4ever » Thu Dec 18, 2008 3:43 pm

Cotten wrote:The longevity of any motor is inversely proportional to how loose the nut on the handlebars might be.

....Cotten
Now that statement is priceless! :mrgreen:

caschnd1
Posts: 606
Joined: Tue Apr 25, 2006 3:45 pm
Bikes: 1949 FL Chopper

Re: What is typical Panhead motor mileagle/life expectancy aprox

#7

Post by caschnd1 » Thu Dec 18, 2008 6:17 pm

Cotten wrote:The longevity of any motor is inversely proportional to how loose the nut on the handlebars might be.

....Cotten
LOL... how true!

I'm closing in on 60K miles since my rebuild. I do have hard valve seats. They haven't fallen out like so many tell you they will. My almost 60K miles includes daily riding through 4 Arizona summers. I did lap the valves in August 2007 because I had the heads apart to weld on new exhaust spigots. Not sure how many more miles I'll get from the top end. No issues with the motor at this point so I'll just keep riding it.

-Craig

Cotten
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Location: Central Illinois

Re: What is typical Panhead motor mileagle/life expectancy aprox

#8

Post by Cotten » Fri Dec 19, 2008 12:31 am

Craig wrote: "I'm closing in on 60K miles since my rebuild. I do have hard valve seats. They haven't fallen out like so many tell you they will."

Craig!

The harden'd seat thang has many, many aspects and uncontrolled variables; (Early heads suffer the worst,... many installers botch them,... etc.)

If your set has survived the test of duty, then you need only prevent any extraordinary temperature spikes to enjoy them for many more miles.

I have a set of my own installation that I fully intend to put into service some day.

But all with such an update must be aware of the risk that they inherently contain: If combustion temperatures exceed the critical point that the seat material can sustain, they just fall out.
Timing must always be dead-on, vacuum leaks are deadly, and always seek out the highest octane fuel available!

...Cotten

caschnd1
Posts: 606
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Re: What is typical Panhead motor mileagle/life expectancy aprox

#9

Post by caschnd1 » Fri Dec 19, 2008 3:47 am

All good tips Cotton. I do keep an eye on the timing and the vacuum leaks. But I run the lowest octane fuel I can with no ping. That means 87 in the winter and 89 in the summer. As far as heat spikes go... yikes. That's a difficult one for me to avoid. My work day is usually 6am - 4pm and at 4pm in July/August/September in Arizona we often see 115F ambient temps. The ride home gets toasty.

-Craig

RussW
Posts: 170
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Bikes: 1961 FL
2007 Kaw. Vulcan 2000
Location: Western Mass

Re: What is typical Panhead motor mileagle/life expectancy aprox

#10

Post by RussW » Fri Dec 19, 2008 4:42 am

My '61 got a ground-up rebuild about 50K ago, with S&S 4.5" stroker wheels. Needed a top end about 25K later when front cylinder broke the top ring. Heads got a clean-up, new pistons@.060 over , valves were still OK. Hardened seats had been installed originally by Dave Macky, guess he did an OK job. Motor runs good, keep waiting for that dreaded "new noise" to develop but nothing yet. If it grenades tomorrow, I'll let you know.....

steve_wood
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Location: Belleville, Ontario, Canada

Re: What is typical Panhead motor mileagle/life expectancy aprox

#11

Post by steve_wood » Fri Dec 19, 2008 11:37 am

RussW:

Just curious, how did you know the top ring was broken? Was there some strange sound? Loss of power?

steve

RussW
Posts: 170
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Bikes: 1961 FL
2007 Kaw. Vulcan 2000
Location: Western Mass

Re: What is typical Panhead motor mileagle/life expectancy aprox

#12

Post by RussW » Fri Dec 19, 2008 2:40 pm

It seemed to kick thru easily on that stroke, compression check was real low on that cylinder. Didn't know what was wrong until I pulled it apart.

kevsett
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Location: Missouri

Re: What is typical Panhead motor mileagle/life expectancy aprox

#13

Post by kevsett » Fri Dec 19, 2008 4:43 pm

Piggybacking with a similar question or two of my own.........I am wondering what kind of mileage stock 50's and 60's panhead motors got back in the day they were created and placed on the road before the heads or lower end needed attention? For instance, heavy duty under LEO use and lighter duty under civilian, personal owner use? Obviously there are numerous factors such as oil type, oil changes, temperatures, frequency of use, frequency and magnitude of abuse, and likely even the gas of yesterday versus todays stuff. 15K? 25K? 40K? 50K? More?

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