Compression ratio for daily rider panhead

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Huck
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Re: Compression ratio for daily rider panhead

#16

Post by Huck »

So what did you do to get the hack bike to quit shakin the pistons?
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Re: Compression ratio for daily rider panhead

#17

Post by Cotten »

Huck wrote:So what did you do to get the hack bike to quit shakin the pistons?
Huck!

I avoided lugging it.

Not easy with anything "hotter" than an FLH cam.
There's a reason why they made FLs...

I guess my point is that "knock" loud enough to hear is a matter of circumstance, and a bad one at that.
Lots of folks have burnt a valve or piston without noticing a thing, and ring land wear prevents most simple overhauls from re-using pistons that would otherwise be... desireable.

....Cotten
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Re: Compression ratio for daily rider panhead

#18

Post by 58flh »

I know I use to set my shortsters timing against a wall,when going out to have fun &(maybe put a few bucks in my pocket!.My buddie just put the wheel on a cinderblock wall & I ADJ. the timing right to the point where it stopd PINGING!--A Pre-detonation is a diff. sound & more Diesel-like is my best way to describe it!.Dieseling sound is from low-octane fuels & Timing not properly set!-So alot of carbon gets built-up on top of piston & all the way down the insulater on the plugs!.These deposits GLOW RED-HOT & Light the mixture prematurely most of the time!--Ive found it to not light at all,& when it does--Its VERY hard on the slugs as well the valves.--In the late 60s you would do the same thing with somebody behind the wheel ,holding the brakes & turn the dist. in your car until QUIET!--Then you can always check what your total ADV. is later.-(The big diff. is there water-cooled & our bikes arent!).But thats an auto,& were talking Big-twins!-- I believe even at 9 to 1 comp./You can stop ping!,It shouldnt ping to begin with! ,unless you get a bad tank of gas!-& on the coast being west or east I have got water in fuel ALOT!--Everyone does!-(I can honestly say that SUNOCOS 94,89,&87-octane gas-I never had a bad tank from!).But all the others & in winter & spring is the worst! to get gas from.The OHV-twinns are very forgiving motors!-----Respectfully---Richie
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Re: Compression ratio for daily rider panhead

#19

Post by Bosheff »

Like Cotton said, to keep em from knockin, don't lug the engine, which also translates into not gearin these things to tall. Usually, like anything else, it's a combination of little things and not just one major change....bosheff
Huck
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Re: Compression ratio for daily rider panhead

#20

Post by Huck »

Clunker asked about cams...
I run the H cam on a low compression motor, It seems to pull really well around 3K, I like it.
Who makes a good copy?
58flh
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Re: Compression ratio for daily rider panhead

#21

Post by 58flh »

Clunker---I run a FLH cam ,like huck!---Its a real nice cam,& like the man said -(I like it!)--I have checked into Black-widow Cams--Who are making the old SIFTONS THAT EVERYBODY LIKES!--They have the original prints & are making the grinds for our pans!--Also custom grinds as Ingram does.-Im purchased a 440 Widow/Sifton grind for my 49-bobber project.The grinds that would interest pan users are the ArisTocrat,cobra,& the others that escape my memory-ALL by (Black-Widow).There are some good crane-grinds ,but there not drop ins!-You have to set spring-hight & some dremmal work in gear case!-its the 296-A by crane!,Alot of guys like this one in a pan!--Clunker you need to find what is in yours & weather it will be a runner or a light-hopper!.Just remember if running daily go mild!-Like stock grinds!-No worries & you will enjoy the bike!.---Respectfully---Richie
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Re: Compression ratio for daily rider panhead

#22

Post by VPH-D »

The old Sifton 412 was a great cam for Pans and Shovels, good bottom end and mid-range. IIRC, it was a drop in cam. I have one in my 51 FL, and like it.
VPH-D
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Re: Compression ratio for daily rider panhead

#23

Post by Bigincher »

My research into a modern substitute for the old Sifton 412 led me to the Andrews J-grind as about the closest that can be had these days.
The Sifton 412 was very close to the old 'H' cam, or 'Victory' cam, I believe it was.
It's also worth pointing out that the Sifton we all knew back in the day has been purchased by V-Twin and now all Sifton products are made in China and are not of the same quality. Most everyone probably already knows that, but maybe not everyone.
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Re: Compression ratio for daily rider panhead

#24

Post by Panhead Ed »

NO MATTER what cam you settle on use a degree wheel to check that the timing events happen happen as stated on the info card . BRAND NEW Cams have frequentlly shown up with the gear installed incorrectly ! your bike might run ,but like shit and send you looking for problems when the problem is the new cam you just installed .

OH YA IT HAPPENS MORE THAN YOU MIGHT THINK ED
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Re: Compression ratio for daily rider panhead

#25

Post by VPH-D »

I bought a new Sifton 468S cam back in the 70s that had the gear pressed on in the wrong position. I didn't notice this until I bent valves...
The Andrews J cam is nice 'small" cam, I have two of them.
VPH-D
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Re: Compression ratio for daily rider panhead

#26

Post by james »

I bought a new in box FLH cam from Harley. Do they still make them or was it nos?

Jim
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Re: Compression ratio for daily rider panhead

#27

Post by VPH-D »

I would guess the cam was NOS. I know the cam was still available in the later 70s, but it probably went obsolete sometime in the 80s.
VPH-D
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