Cam question
Seasoned HDF Member
Joined: Mar 2010
Posts: 21,100
Likes: 7,629
From: Poolville
By the looks of it I would say it's an old school cam with lots of duration but not a fast ramping cam. Which is good for Evo's. If you have a pair of vernier calipers, measure the base circle and then the entire Lobe and post.. That will give me the info I need to calculate lift.. Seeing it's a custom built bike there might be more to the motor but by taking it apart before doing a compression test, we really cannot advise on a suitable cam for an upgrade..
Thread Starter
|
6th Gear
Joined: Dec 2021
Posts: 10
Likes: 0
From: CA
Cam question
By the looks of it I would say it's an old school cam with lots of duration but not a fast ramping cam. Which is good for Evo's. If you have a pair of vernier calipers, measure the base circle and then the entire Lobe and post.. That will give me the info I need to calculate lift.. Seeing it's a custom built bike there might be more to the motor but by taking it apart before doing a compression test, we really cannot advise on a suitable cam for an upgrade..
Seasoned HDF Member
Joined: Mar 2010
Posts: 21,100
Likes: 7,629
From: Poolville
The second picture showing the lobes indicate pretty square lobe which would indicate a fast ramp, definitely.. The fourth picture of the lobes it looks a little different I don't know if it's a shadowing or not. But faster ramp cams will bring the power band in sooner.. It's allowing for earlier cylinder fill and that's one of the elements to making better bottom end torque.. Do you have the rocker covers off? I'd be curious to see what type of springs are being used.. Also did you do a cold compression test before you took it apart? It's always good to get a baseline before making any changes.. I tried looking up the numbers posted and couldn't find anything.. Is this a bottom or a top breather motor? It would help to know that to narrow down the year or you can post up the serial number on the left side case.. And again measure up the lobes, total height and width and post up the numbers... Seeing it's a custom build there might be a lot more to the motor that can't be seen.. but a compression test will help.. If you know some one that has a stock cam N grind cam, install it to do a compression test.. it will give a great indication to where the motor is, making it easier to recommend a cam...
Thread Starter
|
6th Gear
Joined: Dec 2021
Posts: 10
Likes: 0
From: CA
Cam question
The second picture showing the lobes indicate pretty square lobe which would indicate a fast ramp, definitely.. The fourth picture of the lobes it looks a little different I don't know if it's a shadowing or not. But faster ramp cams will bring the power band in sooner.. It's allowing for earlier cylinder fill and that's one of the elements to making better bottom end torque.. Do you have the rocker covers off? I'd be curious to see what type of springs are being used.. Also did you do a cold compression test before you took it apart? It's always good to get a baseline before making any changes.. I tried looking up the numbers posted and couldn't find anything.. Is this a bottom or a top breather motor? It would help to know that to narrow down the year or you can post up the serial number on the left side case.. And again measure up the lobes, total height and width and post up the numbers... Seeing it's a custom build there might be a lot more to the motor that can't be seen.. but a compression test will help.. If you know some one that has a stock cam N grind cam, install it to do a compression test.. it will give a great indication to where the motor is, making it easier to recommend a cam...
Seasoned HDF Member
Joined: Mar 2010
Posts: 21,100
Likes: 7,629
From: Poolville
If the motor is apart then show pics of the cylinder heads n springs and combustion Chambers and the tops of the Pistons if possible.. Then maybe we can make a better education decision.. Just because that was the cam that was in it doesn't not guarantee that it suits the build..
Last edited by 98hotrodfatboy; Dec 31, 2021 at 12:47 PM.
Thread Starter
|
6th Gear
Joined: Dec 2021
Posts: 10
Likes: 0
From: CA
Cam question
This is how I got it with the cam out
Seasoned HDF Member
Joined: Mar 2010
Posts: 21,100
Likes: 7,629
From: Poolville
I would believe that it's a 93 or later Evo motor being a top breather and with the CV carb on there it might have some minor upgrades but nothing real major, I doubt without tearing into it.. You won't know exactly what's in it..
Other than identifying it as a later production top breather, not a lot to go on there.
How hard are you willing to work with this. Probably the "right" thing to do is to pull the heads so you can identify if the valves have been worked over, and also if the pistons have been replaced.
Or you can put a basic cam in it and take your chances. It will run, but maybe not up to snuff relative to the rest of the motor.
What was the guy's story? Why did he think he needed to replace the cam?
How hard are you willing to work with this. Probably the "right" thing to do is to pull the heads so you can identify if the valves have been worked over, and also if the pistons have been replaced.
Or you can put a basic cam in it and take your chances. It will run, but maybe not up to snuff relative to the rest of the motor.
What was the guy's story? Why did he think he needed to replace the cam?
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
10 Things Harley-Davidson Needs to Fix in 2026
Verdad Gallardo
Thread Starter
|
6th Gear
Joined: Dec 2021
Posts: 10
Likes: 0
From: CA
Cam question
Other than identifying it as a later production top breather, not a lot to go on there.
How hard are you willing to work with this. Probably the "right" thing to do is to pull the heads so you can identify if the valves have been worked over, and also if the pistons have been replaced.
Or you can put a basic cam in it and take your chances. It will run, but maybe not up to snuff relative to the rest of the motor.
What was the guy's story? Why did he think he needed to replace the cam?
How hard are you willing to work with this. Probably the "right" thing to do is to pull the heads so you can identify if the valves have been worked over, and also if the pistons have been replaced.
Or you can put a basic cam in it and take your chances. It will run, but maybe not up to snuff relative to the rest of the motor.
What was the guy's story? Why did he think he needed to replace the cam?