Description: Does anyone know how to ID a stock Pan cam
Does anyone know how to ID a stock Pan cam (51FL)? I think the one I have currently is stock but don't know for sure. The only marking on it is a W on the back of the gear.
Thanks
King
Pan cam identification
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Cotten
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Re: Pan cam identification
Stock like original? or stock replacement?
I shouldn't trust my memory, but I think an FL cam has a lift of .409" (You can determine this by either setting it between centers and measuring it with an indicator, or if installed, set the indicator upon a tappet adjustor for a carefull guesstimate. Later FLHs had a .412 lift, I think, and an "H" stamped on the rear intake lobe.)
Originals had a welch plug in the cover-end journal. Note also this journal was about a thou smaller than later needlebearing journals. (.812 compared to .8135" but my memory is fadeing fassst, so please doublecheck!)
I shouldn't trust my memory, but I think an FL cam has a lift of .409" (You can determine this by either setting it between centers and measuring it with an indicator, or if installed, set the indicator upon a tappet adjustor for a carefull guesstimate. Later FLHs had a .412 lift, I think, and an "H" stamped on the rear intake lobe.)
Originals had a welch plug in the cover-end journal. Note also this journal was about a thou smaller than later needlebearing journals. (.812 compared to .8135" but my memory is fadeing fassst, so please doublecheck!)
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King
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Re: Pan cam identification
Thanks Cotten
Reason for the question is, that as I was checking out a new cam for bushing fit and lobe interference, I noticed that, although it reputably has a .450 lift, the lobes did not seem any higher than on the "stock" one that came with the bike (32 years ago).
I measured the lobes from base to tip with an outside caliper and compared the old with the new and they were only a few thousands different. Given the fact (as you noted) that the stock cams have ether .409 or .412 lifts, that was a bit of a head scratcher as I am pretty sure that the old cam is original stock since I know both of the previous owners were not the modifying kind.
Anyway, the new cam fits well (after some journal shaving) and doesn't bump into anything, so after we resolve the gear lash hassle I'll just run it and see what happens.
Thanks again,
King
Reason for the question is, that as I was checking out a new cam for bushing fit and lobe interference, I noticed that, although it reputably has a .450 lift, the lobes did not seem any higher than on the "stock" one that came with the bike (32 years ago).
I measured the lobes from base to tip with an outside caliper and compared the old with the new and they were only a few thousands different. Given the fact (as you noted) that the stock cams have ether .409 or .412 lifts, that was a bit of a head scratcher as I am pretty sure that the old cam is original stock since I know both of the previous owners were not the modifying kind.
Anyway, the new cam fits well (after some journal shaving) and doesn't bump into anything, so after we resolve the gear lash hassle I'll just run it and see what happens.
Thanks again,
King
Re: Pan cam identification
King-
There is a way that a cam would measure about the same & still have higher lift. That is for it to have a "smaller base circle".. The way I measure to compare is to measure from the cam journal to the top of the base (heel) & then from journal to the 'peak of lobe'(highest point) & subtract 1 from the other. That equates to your total lift..
Think about it.. If you measure the entire lobe, you are adding, when you should be subtracting..
Because 'base to journal' amount should be removed from the other measurement. Can't accurately compare unless you know for sure they both have the same 'Base Circles'
Best made cams do. But I still check this way..
You know what I mean ??
There is a way that a cam would measure about the same & still have higher lift. That is for it to have a "smaller base circle".. The way I measure to compare is to measure from the cam journal to the top of the base (heel) & then from journal to the 'peak of lobe'(highest point) & subtract 1 from the other. That equates to your total lift..
Think about it.. If you measure the entire lobe, you are adding, when you should be subtracting..
Because 'base to journal' amount should be removed from the other measurement. Can't accurately compare unless you know for sure they both have the same 'Base Circles'
Best made cams do. But I still check this way..
You know what I mean ??
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Red55FL
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Re: Pan cam identification
King
If you need to find out exactly what the cam is, set the cam journals in a set of V blocks with the gear hanging off the side of the workbench. Mount a degree wheel on the gear with tape or a few dabs of silicone. Make sure the degree wheel Zero is indexed with the cam gear timing mark. Use a bent welding rod or some other wire or rod mounted to your workbench as a pointer on the degree wheel.
Then using a dial indicator on the lobes (Zeroed on the lobe heel), slowly spin the cam in the V blocks and record degree wheel and dial indicator readings. The pointer on the degree wheel needs to be in line with the dial indicator so that it is showing the point in rotation that the dial indicator is reading.
By doing this you can determine lift, duration, overlap and timing. Remember to multiply the lift reading by the rocker ratio.
Red
If you need to find out exactly what the cam is, set the cam journals in a set of V blocks with the gear hanging off the side of the workbench. Mount a degree wheel on the gear with tape or a few dabs of silicone. Make sure the degree wheel Zero is indexed with the cam gear timing mark. Use a bent welding rod or some other wire or rod mounted to your workbench as a pointer on the degree wheel.
Then using a dial indicator on the lobes (Zeroed on the lobe heel), slowly spin the cam in the V blocks and record degree wheel and dial indicator readings. The pointer on the degree wheel needs to be in line with the dial indicator so that it is showing the point in rotation that the dial indicator is reading.
By doing this you can determine lift, duration, overlap and timing. Remember to multiply the lift reading by the rocker ratio.
Red