Explaining How Cams Work and What the Numbers Mean, Parts 1 & 2
Tourer
Joined: Aug 2011
Posts: 336
Likes: 2
From: mentor ohio
Weevil, I just had tw 555 cams and a s&s 106 kit put in my 2012 street glide also have the s&s intake and freedom performance outlaw true dual exhaust and power vision. havent picked the bike up yet but was wondering what you think of this build. thanks
mike
mike
Intermediate
Joined: Jan 2008
Posts: 42
Likes: 0
From: NorCal
Great write up, but difficult to convert into practical application ... at least for me 
In that light I have a question that I hope doesn't put my ignorance too much on display.
I'd like to know if it is possible to get the "potato-potato" sound of old Harley's on the newer models?
I have a '12 FLHX 103" with a full Thunderheader header and muffler exhaust and the Arlen Ness Big Sucker II intake. I typically ride solo and range from puttin' around town to cross country trips. I reckon my RPM range is 2000 to 4500 with highway cruise speeds between 70 and 85 mph (3000 - 4000 rpm).
Could you recommend a cam for me?
In that light I have a question that I hope doesn't put my ignorance too much on display.
I'd like to know if it is possible to get the "potato-potato" sound of old Harley's on the newer models?
I have a '12 FLHX 103" with a full Thunderheader header and muffler exhaust and the Arlen Ness Big Sucker II intake. I typically ride solo and range from puttin' around town to cross country trips. I reckon my RPM range is 2000 to 4500 with highway cruise speeds between 70 and 85 mph (3000 - 4000 rpm).
Could you recommend a cam for me?
Outstanding HDF Member
Joined: Aug 2008
Posts: 3,078
Likes: 6
From: Michigan
You'll love it! see my sig
2nd Gear
Joined: Dec 2009
Posts: 6
Likes: 0
From: Georgia
Weevil,
I don't have the ability to send a private message, so I will try to contact you here. I would like to talk to you about your fine camshaft article and possibly using it on my website. Thank you.
I don't have the ability to send a private message, so I will try to contact you here. I would like to talk to you about your fine camshaft article and possibly using it on my website. Thank you.
Last edited by ChickinOnaChain; Jan 11, 2016 at 08:04 AM.
2nd Gear
Joined: Dec 2009
Posts: 6
Likes: 0
From: Georgia
Road Master
Joined: Aug 2012
Posts: 944
Likes: 2
From: Ct
A great read but still a little overwhelming for a noob trying to learn this stuff.
I mean me.
It would be great if someone who understand this stuff more could pair up some cams with air/exhaust and results.
Like, these cams with this exhaust and air on an otherwise stock bike will produce good torque and less top end hp, which is what most of us are looking for.
I have a 103/6 speed, 2007 Road king police stock.
I am adding pipes and air and a tune to try and pull more torque in the range that I drive, 2 up semi loaded to fully loaded, 100 to 400 miles a day, in the 2000 rpm to 3500 rpm range, I rarely ever go over 3500 rpms.
Taking off loaded on a hill with a passenger or passing a car on a hill under the same circumstances, ie passenger, loaded bags, windshield, trying to get torque in the 3k range.
Stock I have a dead spot or flat spot around 3k when passing you can feel the torque just drop off an thats all the pull I have in that gear, force a shift and hope for the best.
When you add all the variables of different pipes and air kits there must be tons of varied results even with the same motor and cam just from the air and exhaust.
I settled on a set of pipes and air to go with them, my decision was based on my own limited understanding of how stuff works or ignorant common sense.
I selected what I think will provide the most air I can get in there and a set of pipes with very good test results in the mid range area and rpm range I drive.
My local Harley service tech told me the se 255;s came with the newer 103's after 08, when I asked if they thought the se 255 would help me with the torque and rpm range I was looking for improvements.
I am using a hackerscustom bagger mayhem pipe, pictured below
and either the S&S dual induction single bore efi air kit, or the ness twin sucker, both look too be nearly the same, s&s looks better to me.
If this is my combo with a stock cam, which cam would offer me an improvement in mid range from stock, ie: 2000 rpms to 3300 rpms ?
Would it be an increase worth the money and by that I mean a noticeable difference in power and low end torque from the rear wheel while in the seat on the road?
On a budget so I am not looking to spend money for the sake of making claims with fancy terms or brag about cams I dont understand.
I guess it would need to be 15% or better performance to justify the cost for me.
I am thinking from stock to the air and pipes alone will be a huge increase and lower running temps with good sound and power, so is it worth a cam swap also?
I mean I am sure it is always worth it if you want any increase at all, or to squeeze every drop of torque out of your engine but again I am not racing only touring 2 up and looking to eliminate the dead spots around 3k rpms so when I m traveling 50 mph at 2200 rpms and we hit a hill where I have to slow down just before a passing lane appears and then I can downshift and pass with ease while climbing to 3200 rpms or so.
Anyway sorry for the long post, I love the point of the article written here but it is still a little overwhelming to me and if anyone had any good input or real world experience with this set up I would appreciate the input very much.
Thanks and again great thread.
Lump
I mean me.
It would be great if someone who understand this stuff more could pair up some cams with air/exhaust and results.
Like, these cams with this exhaust and air on an otherwise stock bike will produce good torque and less top end hp, which is what most of us are looking for.
I have a 103/6 speed, 2007 Road king police stock.
I am adding pipes and air and a tune to try and pull more torque in the range that I drive, 2 up semi loaded to fully loaded, 100 to 400 miles a day, in the 2000 rpm to 3500 rpm range, I rarely ever go over 3500 rpms.
Taking off loaded on a hill with a passenger or passing a car on a hill under the same circumstances, ie passenger, loaded bags, windshield, trying to get torque in the 3k range.
Stock I have a dead spot or flat spot around 3k when passing you can feel the torque just drop off an thats all the pull I have in that gear, force a shift and hope for the best.
When you add all the variables of different pipes and air kits there must be tons of varied results even with the same motor and cam just from the air and exhaust.
I settled on a set of pipes and air to go with them, my decision was based on my own limited understanding of how stuff works or ignorant common sense.
I selected what I think will provide the most air I can get in there and a set of pipes with very good test results in the mid range area and rpm range I drive.
My local Harley service tech told me the se 255;s came with the newer 103's after 08, when I asked if they thought the se 255 would help me with the torque and rpm range I was looking for improvements.
I am using a hackerscustom bagger mayhem pipe, pictured below
and either the S&S dual induction single bore efi air kit, or the ness twin sucker, both look too be nearly the same, s&s looks better to me.
If this is my combo with a stock cam, which cam would offer me an improvement in mid range from stock, ie: 2000 rpms to 3300 rpms ?
Would it be an increase worth the money and by that I mean a noticeable difference in power and low end torque from the rear wheel while in the seat on the road?
On a budget so I am not looking to spend money for the sake of making claims with fancy terms or brag about cams I dont understand.
I guess it would need to be 15% or better performance to justify the cost for me.
I am thinking from stock to the air and pipes alone will be a huge increase and lower running temps with good sound and power, so is it worth a cam swap also?
I mean I am sure it is always worth it if you want any increase at all, or to squeeze every drop of torque out of your engine but again I am not racing only touring 2 up and looking to eliminate the dead spots around 3k rpms so when I m traveling 50 mph at 2200 rpms and we hit a hill where I have to slow down just before a passing lane appears and then I can downshift and pass with ease while climbing to 3200 rpms or so.
Anyway sorry for the long post, I love the point of the article written here but it is still a little overwhelming to me and if anyone had any good input or real world experience with this set up I would appreciate the input very much.
Thanks and again great thread.
Lump
Last edited by lumper; Apr 29, 2013 at 02:09 PM.
Intermediate
Joined: Jun 2013
Posts: 15
Likes: 1
From: Lafayette tn
I am wondering what to do with my 98 ultra? she has 60k miles, true duals, big breather and needs more grunt in the mid range. Around 2500 - 3000 rpm is where I spend most of my time and I have been told to just put in a bigger cam and another said to do a upgrade to include new jugs, heads, pistons etc... to make it a 88c.i. What can I do to get the most torque in the mid range and not break the bank doing it?
Road Warrior
Joined: May 2011
Posts: 1,956
Likes: 437
From: florida
A great read but still a little overwhelming for a noob trying to learn this stuff.
I mean me.
It would be great if someone who understand this stuff more could pair up some cams with air/exhaust and results.
Like, these cams with this exhaust and air on an otherwise stock bike will produce good torque and less top end hp, which is what most of us are looking for.
I have a 103/6 speed, 2007 Road king police stock.
I am adding pipes and air and a tune to try and pull more torque in the range that I drive, 2 up semi loaded to fully loaded, 100 to 400 miles a day, in the 2000 rpm to 3500 rpm range, I rarely ever go over 3500 rpms.
Taking off loaded on a hill with a passenger or passing a car on a hill under the same circumstances, ie passenger, loaded bags, windshield, trying to get torque in the 3k range.
Stock I have a dead spot or flat spot around 3k when passing you can feel the torque just drop off an thats all the pull I have in that gear, force a shift and hope for the best.
When you add all the variables of different pipes and air kits there must be tons of varied results even with the same motor and cam just from the air and exhaust.
I settled on a set of pipes and air to go with them, my decision was based on my own limited understanding of how stuff works or ignorant common sense.
I selected what I think will provide the most air I can get in there and a set of pipes with very good test results in the mid range area and rpm range I drive.
My local Harley service tech told me the se 255;s came with the newer 103's after 08, when I asked if they thought the se 255 would help me with the torque and rpm range I was looking for improvements.
I am using a hackerscustom bagger mayhem pipe, pictured below
and either the S&S dual induction single bore efi air kit, or the ness twin sucker, both look too be nearly the same, s&s looks better to me.
Attachment 312466
Attachment 312468
If this is my combo with a stock cam, which cam would offer me an improvement in mid range from stock, ie: 2000 rpms to 3300 rpms ?
Would it be an increase worth the money and by that I mean a noticeable difference in power and low end torque from the rear wheel while in the seat on the road?
On a budget so I am not looking to spend money for the sake of making claims with fancy terms or brag about cams I dont understand.
I guess it would need to be 15% or better performance to justify the cost for me.
I am thinking from stock to the air and pipes alone will be a huge increase and lower running temps with good sound and power, so is it worth a cam swap also?
I mean I am sure it is always worth it if you want any increase at all, or to squeeze every drop of torque out of your engine but again I am not racing only touring 2 up and looking to eliminate the dead spots around 3k rpms so when I m traveling 50 mph at 2200 rpms and we hit a hill where I have to slow down just before a passing lane appears and then I can downshift and pass with ease while climbing to 3200 rpms or so.
Anyway sorry for the long post, I love the point of the article written here but it is still a little overwhelming to me and if anyone had any good input or real world experience with this set up I would appreciate the input very much.
Thanks and again great thread.
Lump
I mean me.
It would be great if someone who understand this stuff more could pair up some cams with air/exhaust and results.
Like, these cams with this exhaust and air on an otherwise stock bike will produce good torque and less top end hp, which is what most of us are looking for.
I have a 103/6 speed, 2007 Road king police stock.
I am adding pipes and air and a tune to try and pull more torque in the range that I drive, 2 up semi loaded to fully loaded, 100 to 400 miles a day, in the 2000 rpm to 3500 rpm range, I rarely ever go over 3500 rpms.
Taking off loaded on a hill with a passenger or passing a car on a hill under the same circumstances, ie passenger, loaded bags, windshield, trying to get torque in the 3k range.
Stock I have a dead spot or flat spot around 3k when passing you can feel the torque just drop off an thats all the pull I have in that gear, force a shift and hope for the best.
When you add all the variables of different pipes and air kits there must be tons of varied results even with the same motor and cam just from the air and exhaust.
I settled on a set of pipes and air to go with them, my decision was based on my own limited understanding of how stuff works or ignorant common sense.
I selected what I think will provide the most air I can get in there and a set of pipes with very good test results in the mid range area and rpm range I drive.
My local Harley service tech told me the se 255;s came with the newer 103's after 08, when I asked if they thought the se 255 would help me with the torque and rpm range I was looking for improvements.
I am using a hackerscustom bagger mayhem pipe, pictured below
and either the S&S dual induction single bore efi air kit, or the ness twin sucker, both look too be nearly the same, s&s looks better to me.
Attachment 312466
Attachment 312468
If this is my combo with a stock cam, which cam would offer me an improvement in mid range from stock, ie: 2000 rpms to 3300 rpms ?
Would it be an increase worth the money and by that I mean a noticeable difference in power and low end torque from the rear wheel while in the seat on the road?
On a budget so I am not looking to spend money for the sake of making claims with fancy terms or brag about cams I dont understand.
I guess it would need to be 15% or better performance to justify the cost for me.
I am thinking from stock to the air and pipes alone will be a huge increase and lower running temps with good sound and power, so is it worth a cam swap also?
I mean I am sure it is always worth it if you want any increase at all, or to squeeze every drop of torque out of your engine but again I am not racing only touring 2 up and looking to eliminate the dead spots around 3k rpms so when I m traveling 50 mph at 2200 rpms and we hit a hill where I have to slow down just before a passing lane appears and then I can downshift and pass with ease while climbing to 3200 rpms or so.
Anyway sorry for the long post, I love the point of the article written here but it is still a little overwhelming to me and if anyone had any good input or real world experience with this set up I would appreciate the input very much.
Thanks and again great thread.
Lump