Topic: Stock Valve Spring Seat Pressure??? (Read 5828 times)

skippy49 · « **on:** February 20, 2006, 02:11:11 PM »

Does anyone know the valve seat pressure with the springs that come stock with the CVO heads? The particular bike I'm interested in, if it makes a difference, is the 03 SERK. I'm thinking of switching to a different cam that suggests 160# seat pressure but I don't know what the stock setup is. Also what is the maximum lift allowed with the stock springs, if anyone's measured?
Thanks for any help.
Hopefully I'll get into this yet this week.
Steve

kng103 · « **Reply #1 on:** February 20, 2006, 10:14:00 PM »

Quote

Does anyone know the valve seat pressure with the springs that come stock with the CVO heads?

electraglidese · « **Reply #2 on:** February 20, 2006, 10:35:56 PM »

I was told by my local dealer that our cvo valve springs will handle .575 lift. If you haven't looked at Bob Woods cams check out his web site and look at the TW5g a real torq monster. Plus some of the guys on these forums claim the TW5g Gear Drive is not as noisy, more torq than HP on dynos.

skippy49 · « **Reply #3 on:** February 21, 2006, 08:10:34 AM »

I hadn't looked at that cam, but I have read several places that woods cams are noisy. What's the opinion about the noise? I may call Bob anyway and see what he says.
I'd still like to know the stock spring seat pressure if anyone knows. If not I'll give the moco a call as suggested.

It'd be nice to use a bolt in cam-sure would save me some work, but I don't think I can wait until Zippers comes out with their new 575, due to my work schedule. There's just too many cam choices out there-everytime I think I get it narrowed down, someone gives me another one to look at-and then the new one looks good! [smiley=nixweiss.gif]

HUBBARD · « **Reply #4 on:** February 21, 2006, 10:07:41 AM »

Yeah, 'er 'uh, skippy49,
I think your stock valve seat pressure is between 100 & 120 #. I may not be exactly right, but I'm close. Later--HUBBARD

SPIDERMAN · « **Reply #5 on:** February 21, 2006, 12:03:23 PM »

Hubbard
In a perfect world isn't the seat pressure a factor of the cam profile ? I mean you wouldn't want 120lbs on a .650 lift nor would you want 180lbs on a 530 lift - - - correct ?

Big B

grc · « **Reply #6 on:** February 21, 2006, 12:42:34 PM »

Quote

Does anyone know the valve seat pressure with the springs that come stock with the CVO heads?

skippy49 · « **Reply #7 on:** February 21, 2006, 12:58:35 PM »

The parts manual for my 03 SERK list the springs as #18272-00, but I can't find that # anywhere, that's why I was wondering if anyone knew what they were. I may call the dealer and see if they know what spring it is.
I'm guessing that the #18273-00 is the same as the spring I have, only it includes the upper and lower collars and keepers, whereas my number is only the springs themselves and the collars and keepers have separate part numbers in the book. Don't know for sure, but I'd bet on it.
Steve

HUBBARD · « **Reply #8 on:** February 21, 2006, 01:20:39 PM »

Quote

Hubbard
In a perfect world isn't the seat pressure a factor of the cam profile ? I mean you wouldn't want 120lbs on a .650 lift nor would you want 180lbs on a 530 lift - - - correct ?

Big B

Yeah, 'er 'uh, shippy49,
That's exactly right. For example, Ol' Maudie has RedShift 647 Gear Drive Cams. .647 Lift, .264 Duration. Valve Seat Pressure on mine is 200 lbs. Later--HUBBARD

skippy49 · « **Reply #9 on:** February 21, 2006, 02:30:55 PM »

Quote

Yeah, 'er 'uh, shippy49,
That's exactly right. For example, Ol' Maudie has RedShift 647 Gear Drive Cams. .647 Lift, .264 Duration. Valve Seat Pressure on mine is 200 lbs. Later--HUBBARD

Valve seat pressure is measured at an installed height. Specific springs have a specific seat pressure at a specific installed height. I'm just trying to find out what is the seat pressure at the installed height of the stock springs in a CVO 103. If the springs are the ones that I think they are in the SE catalog, then I know the seat pressure and installed height. It doesn't necessarily mean that I'm going to use them with the cam I use. But it will help determine if they can be used with a different cam that has specific requirements for springs.
I'm guessing they are the same as the set in the catalog with the 18273#, but I may call the dealer to see if they know for sure, and they probably don't.

HUBBARD · « **Reply #10 on:** February 21, 2006, 04:16:18 PM »

Quote

Valve seat pressure is measured at an installed height.

skippy49 · « **Reply #11 on:** February 21, 2006, 09:06:56 PM »

I'll try him tomorrow and see what he says.

HUBBARD · « **Reply #12 on:** February 22, 2006, 09:58:15 PM »

Quote

I'll try him tomorrow and see what he says.

Yeah, 'er 'uh, skippy49,
Did you get up with Neal? Please advise. Later--HUBBARD

skippy49 · « **Reply #13 on:** February 23, 2006, 10:19:51 AM »

Hubbard:
I talked to Neil today and he wasn't sure about the springs on our heads. He said that most of the harley springs were actually less than what Harley advertised them at and, most likely, the springs in our heads would test out at around 100-120#.
I'm going to see if my local machine shop can measure seat pressure and get them checked. If they can't, I'll just put some new ones in.
Steve

syclone · « **Reply #14 on:** February 23, 2006, 11:27:13 AM »

100-120 lbs closed at installed height would really be a surprize (not that low).

skippy49 · « **Reply #15 on:** February 23, 2006, 01:01:03 PM »

Yeah, the Zippers 575 and the S&S 570 are pretty close on the specs, but the 570 is available now and I can put it in now. I don't think I'll have time to do it later, so that means putting it off until next winter. Think I"ll have the shop check my springs before I decide on them.

HUBBARD · « **Reply #16 on:** February 23, 2006, 01:15:47 PM »

Quote

Hubbard:

syclone · « **Reply #17 on:** February 23, 2006, 01:17:47 PM »

Thats why I mentioned the S&S Skippy ....I even like the the slightly lower lift on the 570 (ramps not as steep) and I like the earlier exhaust open at 55 degrees...heads dont have great port velocity so they can use the help .

Unbalanced · « **Reply #18 on:** February 23, 2006, 04:16:40 PM »

This is with the CNC HEADWORK from Zippers,

Total compression ratio is 10.0 to 1 using SE high compression pistons which require no second op work.

skippy49 · « **Reply #19 on:** February 23, 2006, 06:24:17 PM »

Sounds like the stock springs are what I need. What's everyone's opinion on replacing them with new ones? My bike has 23,000 on it and I don't intend to open it back up unless I have to, so should I go ahead and buy new springs? If I do, do I need new collars and everything or just the springs? The reason I ask is that the individual springs are fairly inexpensive compared to the whole kit of new springs. I think the individual springs - inner and outer-are around $6 each. Haven't priced the complete set but I assume they would be $75 to $100 or more.

HUBBARD · « **Reply #20 on:** February 23, 2006, 07:15:57 PM »

Quote

Sounds like the stock springs are what I need.

skippy49 · « **Reply #21 on:** February 23, 2006, 08:13:49 PM »

I don't want to open it up again if I don't have to, and I am changing cams, so I'll see if I can get the whole spring package at the dealer.

skippy49 · « **Reply #22 on:** February 23, 2006, 08:14:40 PM »

On the other hand, I may wait until the shop checks mine to see where I stand.

Author Topic: Stock Valve Spring Seat Pressure??? (Read 5828 times)

SPIDERMAN