Comp Cam preload
Thread Starter
|
Road Master
Joined: Nov 2011
Posts: 1,123
Likes: 117
From: New Jersey
Comp Cam preload
Looking to find the preload for Comp Cams 850-1 lifters.
Replacing a bad set of Fuelings.
Bike is a 2013 Sg with SE adjustable pushrods.
Searched and found a few different answers.
Looking for the right preload.
Thanks in advance.
Tom
Replacing a bad set of Fuelings.
Bike is a 2013 Sg with SE adjustable pushrods.
Searched and found a few different answers.
Looking for the right preload.
Thanks in advance.
Tom
Grand HDF Member
Joined: May 2010
Posts: 3,599
Likes: 5,175
From: SWMO
What's the total travel? Most are .200" or thereabouts. Lifter manufacturers will tell you the center of the travel, .100", is correct. I've set them as deep as .150" with no problems.
I think the correct answer is less than .200" and more than .100".
I think the correct answer is less than .200" and more than .100".
Seasoned HDF Member
Joined: Jan 2013
Posts: 10,637
Likes: 1,246
From: Lake, Ms
There is really no wrong or right answer as long as there's some common sense used. You definitely don't wanna be less than .100 and I don't think you'd wanna go deeper than .150. I have set at .130 on my S&S premiums.
2010 Limited with some stuff
Outstanding HDF Member
Joined: Jun 2012
Posts: 2,087
Likes: 22
From: USA
I just installed 850-01s and also have SE adjustable push rods and went 3 turns plus 1 flat. I started at 2 turns plus 5 flats and the 2 extra flats quieted it down and I have Woods cams. Others are running at 3.5 turns with no problems so somewhere between 3-3.5 should be your sweet spot for noise.
Thread Starter
|
Road Master
Joined: Nov 2011
Posts: 1,123
Likes: 117
From: New Jersey
Trending Topics
Screaming Eagle adjustables are 24 TPI (Threads per Inch ) 1" divided by 24 = .41
1 complete turn = .041 A Hex = 6 flats ,there is always 6 flats to a turn.
1 turn = 6 flats = .041
2 turns = 12 flats = .082
2 1/2 turns = 15 flats = .102
3 turns = 18 flats = .123
1 complete turn = .041 A Hex = 6 flats ,there is always 6 flats to a turn.
1 turn = 6 flats = .041
2 turns = 12 flats = .082
2 1/2 turns = 15 flats = .102
3 turns = 18 flats = .123
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
Cruiser
Joined: Oct 2010
Posts: 182
Likes: 13
From: Ohio
In theory you only need enough pre-load to compensate for growth when things heat up. The lifters will run fine thru their entire range of plunger travel and only need the plungers deep enough to compensate for any additional clearance added from cold to hot engine.
I have found in recent years, especially with current production OEM lifters that they have inconsistencies in leak down rates so tend to make less noise the deeper that you run the plungers into the lifter bodies.
For standard travel lifters, not limited travel, they are going to be happier when you have the plungers at least .100" into the lifter bodies. So 3 turns is a good place to be, and where I set most of them here.
These engines are not a high rpm design, but do have considerably heavy parts above the lifters to keep in check. For the most part the stock lifters do fine, as these engines seldom see much past 5000rpm's or so in most builds. If you are running high rpm's, aggressive camshafts, etc, it may help to use limited travel lifters, or set the standard lifters with less travel under the plungers, or deeper into the lifter bodies.......Cliff
I have found in recent years, especially with current production OEM lifters that they have inconsistencies in leak down rates so tend to make less noise the deeper that you run the plungers into the lifter bodies.
For standard travel lifters, not limited travel, they are going to be happier when you have the plungers at least .100" into the lifter bodies. So 3 turns is a good place to be, and where I set most of them here.
These engines are not a high rpm design, but do have considerably heavy parts above the lifters to keep in check. For the most part the stock lifters do fine, as these engines seldom see much past 5000rpm's or so in most builds. If you are running high rpm's, aggressive camshafts, etc, it may help to use limited travel lifters, or set the standard lifters with less travel under the plungers, or deeper into the lifter bodies.......Cliff
Thread
Thread Starter
Forum
Replies
Last Post
