Panhead weak points or sensible mods etc.

[MartinsFLH]

Hi, I maybe have chance of a 58 Panhead motor . I have some questions for those sages on Panheads. -
First, I am familiar with Shovel engines and working on them etc. and I know the Pan of course to be very similar but I have no experience of working on one. So -
What points have I to look out for, what are the weak points and what can be trouble and "upgraded?" I hate that word because people use it as in- "upgrading to a stroker"( which to me isn't!). The engine will remain a 74"
Is the original oil pump ok or should it be, ahem, "upgraded"
For instance I hear they are prone to cracked heads? What areas do they crack? Should the valve seats be messed with?
Where exactly should the belly numbers be situated? can you get barrels or good aftermarket ones if need be? Etc. Etc.
What are good mods to do for reliability etc?
Finally as its just motor and box I will need a frame so is the Paughco rigid frame any good? I intend if I got the engine and box to make a nice ridable bobber.
Sorry for all the questions. Martin.

[Cotten]

Martin!

Many of us seek in earnest hardware that has not been "upgraded".

Maybe we are just sentimental old curmudgeons,
but please remember that these machines did not become legendary for their fragility, but for their durability.

Many of the "upgrades" incorporated by the MOCO itself made them profits, but also shortened the fuse on the bomb.
(Just one example would be the '58 conversion to an inboard cam needle bearing instead of a bushing.)

I caution you to only fix what needs it.
Most "modernization" is already incorporated into the available replacement parts, whether they needed it or not!

....Cotten

[1964FLDUO]

Panheads can tend to leak from the rocker covers, not a big issue, just makes the heads dirty. They also all leak oil from the cranckcase breather, so you will have oil on your garage floor inevitably. If your mechanically inclined, have an understanding of engines and recognize that they aren't Evos and will need to be worked on if you want to ride em. As far as the Paughco frame I don't think you can go wrong, at least it isn't made in Taiwan like some other company's.

[Huck]

they crack from the plug hole to the valve seat.
after you check everything they crack while you're not looking.
Hippys do stupid stuff to them with welders.
the nipples fall off.
the intakes refuse to seal.
you can't tighten short reach plugs that much WTH?
the threads pull on the valve covers after it's in the frame.
those little pins that hold the rockers are a bitch to find.
it sounds like it has marbles rolling around under the covers.
very few people know how to fix them.
they can be a complete train wreak and still run!
I love my 58!
if it'll run ride it, oil's cheap.

[1964FLDUO]

they crack from the plug hole to the valve seat.
after you check everything they crack while you're not looking.
Hippys do stupid stuff to them with welders.
the nipples fall off.
the intakes refuse to seal.
you can't tighten short reach plugs that much WTH?
the threads pull on the valve covers after it's in the frame.
those little pins that hold the rockers are a bitch to find.
it sounds like it has marbles rolling around under the covers.
very few people know how to fix them.
they can be a complete train wreak and still run!
I love my 58!
if it'll run ride it, oil's cheap.

Well said, Huck.

[58flh]

Martin-----Ito run a 58flh motor, Huck summed it up real nice-(if your use to putting in gas & pushing a button--Its the other end of the spectrum) As to the questions you have asked Look at the Posts In the (knowledge base) section of this site---Valuable info on everything you asked! & Yes they are durable - I ride mine 10 months out of the year for well over 20 years now--With 2 overhauls---when I got it as a basket-& I think 9-10yrs ago. I pull heads every 2 yrs just to visually check stuff If needed or not!----Once a pan is broke-in then do regular preventive maintenance!-they trat you good. I roll on a rigidframe so my intervals are 4-500 miles depending how hard i push it. If you build your motor to live in a good rpm range itll run forever -I can stay doin 70mph about 3000rpm. Its what you want & need it for. GOOD-LUCK on your project & keep the boys up to date as you go---There are some great mechanics on this site/& a good bunch of guys!--Richie-(58flh)

[MartinsFLH]

Thanks for all the replies guys.
Its all the little things which owners having and riding one I wanted to know and you have filled me in on.
Yes, I am used to (and love) working on and riding bikes for the past 40 years. BSA's, Ariel,Triumphs, Nortons, etc. All I wish I still had now! Bought in the days when you could pick an old triumph rigid or sprung hub for peanuts! Sold my last lot of pre unit triumph engines and parts to buy my first Shovel(75FLH) back in 82 which I still have.
I always wanted a Pan. I still have a pic of me sat on a 54 Hydraglide Pan back when I was 14. I used to watch the owner start it and loved the sound. I Love the look of the engine/ Pans.
Hopefully the owner of the engine/tranny I am chasing will still sell and doesn't change his mind (I dont get to know for a few months).
Anymore tips or pointers, quirks of the engine etc, is always welcome.

[caschnd1]

I've experimented with a lot of different modifications to my panhead. I'm not going for performance modifications. I'm looking for reliability and reduced maintenance (I average 300 miles / week so I don't want to always be wrenching).

When I built my motor in 2003 I made the following modifications hoping to improve reliability:

1) Dual Plugged Heads - Improves fuel burn - cosmetically it screws up the heads. Don't do this mod if you want a stock looking bike.

2) Electronic ignition - Very reliable and easy starting. Only have to adjust the timing if I've removed the circuit breaker or moved it. Once it's set, no adjustment needed. The "circuit breaker" no longer looks stock, but easy to go back to stock if you want to later.

3) Evo Lifter Blocks - Bullet proof valve train. Requires no adjustments after the initial setup. These parts again don't look like stock parts.

4) CV40 carb - Easy starting, never have to mess with it. I get 40+mpg around town, 62mpg on the highway (my bike is sub 500# so it's light, and it's geared high for cruising on the highway).

I wouldn't recommend any of these mods if you want a "stocker". But if you want a very reliable bike that can go a lot of miles every week without having to spend an afternoon in the garage every Sunday I think they have been good modifications.

Since 2003 I put over 90K miles on this bike. Back in May I rode it from Arizona to the east coast. Spent a few weeks riding around there and then rode it home. Over 6000 miles. During the entire trip I could barely squeeze a quart of oil into the oil bag. When I got home I decided it was time to at least pull off the top end and see how things were doing (had developed a base gasket leak the last two days of the trip). I ended up freshing up the heads and installing new rings and breaking the glaze on the cylinders. Not much motor work needed for >90K miles.

-Craig

[Cotten]

Martin!

Bringing it back to classic hardware,
a 12v charging system is certainly convenient.

....Cotten

[Speeding Big Twin]

Hi, I maybe have chance of a 58 Panhead motor. I have some questions for those sages on Panheads. -
First, I am familiar with Shovel engines and working on them etc. and I know the Pan of course to be very similar but I have no experience of working on one. So -
Where exactly should the belly numbers be situated? Martin.

Martin, welcome to the forum. Panhead belly numbers are usually on the underside of each crankcase half near the outer edges and somewhat toward the front. They’re in the same location as the belly numbers I’d expect to find on your 1975 Shovelhead.

However, the usual belly number format for a 58 Pan is different to the usual format for a 75 Shovel. A 75 Shovel format would usually be similar to the following example: 175 123 123. But for a 58 Pan, the belly number format should be similar to the next example: 158-1234(5). Or perhaps even one year earlier—for example: 157-1234(5). Also, belly numbers on a couple of 1958 Panheads have been seen with code number 3 at the start instead of code number 1 so you may find something like 358-1234(5).
Eric

[Hauula Pan]

I wrote earlier but it didn't post so I'll try again if I can remember what I said. Mostly Panheads are very reliable if put together properly & they're usually pretty forgiving. You'll notice tolerances are much looser than more modern engines & you can get away with a lot of wear & they'll keep on running. The 2 biggest things I can think of that are major headaches are Intake Manifold Leaks which will cause all kinds of problems from hard starting, poor running, overheating, and many more so Make Darn Sure you don't have any. You will find they don't run much oil pressure when warmed up, you will start of with around 30psi cold & it will drop to as low as 3 to 5 psi when warmed up. Not an issue, its normal, as long as you have oil returning to the tank you have adequate oiling. The threads for the Pan covers often get worn out & need to be repaired, I've seen several that had stripped holes & people just use a nut nuder the lip but some holes don't go through & you can't use a nut & have to fix the threads. A lot of heads will have cracks that go from the valve seat to the spark plug hole, while this should be repaired I've seen several run for years with the cracks. In fact I have one now & my motor runs fine. The Linkert carb. can develop leaks and the floats can stick & many people have had them spit back & catch fire because gas soaked the air cleaner element. Timing needs to be dead on or you'll have hard starting issues. OK those are the quirks I'm aware of. For the most part, they're very forgiving motors that will take a lot of abuse & wear & tear & keep on running. If you're familiar with shovel heads you won't have any problem learning the Pan. Just make sure its put together right & it'll be as reliable as any other motor.

[kitabel]

Re: "Evo Lifter Blocks - Bullet proof valve train. Requires no adjustments after the initial setup.

???

[Cotten]

........ The Linkert carb. can develop leaks and the floats can stick & many people have had them spit back & catch fire because gas soaked the air cleaner element. ......

Hauula Pan!

If the aircleaner is "gas soaked", it would seem we have an operator error!
And you already covered the "spit back" when you addressed the intake leak syndrome.

Martin,

If you intend to scratch-build the entire machine, you are only limited by your resourcefullness.
(That means other things than money, too.)

It will be an achievement you can truly be proud of.
And one that nobody else can work on.

Kitabel asked,
Re: "Evo Lifter Blocks - Bullet proof valve train. Requires no adjustments after the initial setup.

???

You got me Kitabel.
I have no experience with Evo hardware (or at least recollection of it), but I always thought ordinary OEM hydraulics were set-em-and-forget-em too.

....Cotten

[kitabel]

Electronic is an improvement in that the setting doesn't move as the point gap wears.
On the other hand, do you want to carry a spare module with you all the time? When they go, they're one - wiggling the wires and cursing (which is helpful with points) does nothing.

[Hauula Pan]

Oh yeah one more quirk to watch for if you have the old style fuel shut off make sure it actually shuts off. This is one cause of some of those carb. fires I mentioned earlier. A combination of a shut off that allows fuel to keep flowing, along with a sticking float can cause the carb. to leak, usually it will just run out the vent & make a mess, but I've known them to also fill the throat & if you try to kick it over with the timing advanced that's when you get the spit & fire. Yes it is a combination of mechanical malfunction combined with operator error, that error usually being not retarding the spark, but I've seen it happen & the result can be just a minor spout of flame or a major fire depending on how much gas & fumes you're dealing with. One last quirk is depending on what year tanks you run you need to know if you have to run 2 vented gas caps or just 1. Earlier tanks do not have the cross over vent at the top so you have to run 2 vented caps. Problem here is if you fill the left tank & put the bike on the side stand gas is going to pour out of that left cap. You'll need to learn what your bike likes as far as starting procedure too. Most like a couple of primer kicks with ignition off when cold along with a little choke & fully retarded timing, & when warm no choke or prime, just switch on & kick it mine likes the timing about 1/2 advance when warm. Each will have its own, "personality" & once you learn what yours' likes it will be the same procedure every time. If you aren't staying stock you can, "upgrade" the carb. & ignition to just about anything you want. & go to a 12 volt system. That's a subject I won't comment on other than to say its been s source of many a debate on this forum. Personally I love my 6 volt system. Basically it all depends on what you want to do with Your bike. Stock, simi-stock, modified, chopped, bobbed, what ever. Build it the way You want it, but build it & keep the old iron on the road ! Hope we've been of some help to you & keep coming back, everyone here is here for the same reason. Helping one another & keeping the classics on the road.