Please login or register.

Login with username, password and session length
Advanced search  

Author Topic: Easy way to check spring spacing for bigger cam  (Read 2535 times)

0 Members and 1 Guest are viewing this topic.

ltank

  • 1K CVO Member
  • *
  • Offline Offline
  • Posts: 1214
    • LA

    • CVO1: 2000 FXR4 S&S V111, CustomS.S. 2-1 exhaust, Primo-Rivera OD 6 speed, 49mm Custom Front End Ohlins 30mm Fork cartridges , Hyperpro Shocks, Barnett Scorpian Clutch
    • CVO2: 1983 88" Shovelhead Won the World of Wheels 1985 Sept 85 Issue of Hot Bike Mag
    • CVO3: 1989 FXRS, 1990 Custom 100" Shovelhead/ EVO
Easy way to check spring spacing for bigger cam
« on: December 13, 2018, 07:34:02 PM »

S&S built  me Custom V124 with 10.2:1 compression and a 585 cam. Bike runs fine but now I want  more power. I want to install a 600 cam. S&S looked up VIN but can't tell me what the spring packing  was set for.
Normally motor has a 640 cam but I don't know it they set it for the 585 cam that won't  work for the 600 cam. Is there an easy way to check without removing the heads? If I remove the heads then I gotta remove  the cylinders replace  the base gaskets too and new piston  rings. A big hassle but that's the safest thing  I guess.  Can I remove  the forward rocker box, install the new cam and measure the spring  oil seal to collar clearance? Or am I missing  something.  Any help is appreciated. Thanks
Logged

MCE

  • Guest
Re: Easy way to check spring spacing for bigger cam
« Reply #1 on: December 19, 2018, 09:29:54 AM »

Leave the piston in the cylinder. Just pull the pin out and leave the piston in the bore, if it comes to that.
(Saves you from disturbing the rings at least)

You'll probably have to pull a head and use the Trock fixture to test the spring compressed height and
clearance. It helps to know what springs (part #) were installed too. Then check those with a spring
tester at the installed/compressed heights.

Otherwise you'd be guessing. Feeling lucky? lol
Logged

johnsachs

  • Vendor
  • Elite CVO Member
  • *
  • Offline Offline
  • Posts: 747
Re: Easy way to check spring spacing for bigger cam
« Reply #2 on: December 19, 2018, 06:04:48 PM »

S&S built  me Custom V124 with 10.2:1 compression and a 585 cam. Bike runs fine but now I want  more power. I want to install a 600 cam. S&S looked up VIN but can't tell me what the spring packing  was set for.
Normally motor has a 640 cam but I don't know it they set it for the 585 cam that won't  work for the 600 cam. Is there an easy way to check without removing the heads? If I remove the heads then I gotta remove  the cylinders replace  the base gaskets too and new piston  rings. A big hassle but that's the safest thing  I guess.  Can I remove  the forward rocker box, install the new cam and measure the spring  oil seal to collar clearance? Or am I missing  something.  Any help is appreciated. Thanks
Why would you need to replace the piston rings because you pulled the cylinders off if they aren't worn out of specs ?  ???
There is a jig made that may allow you to remove the valve springs with the engine in the frame. Check 1 intake and 1 exhaust. S&S is fairly consistent on their installed heights(valve protrusion) from cylinder to cylinder. Usually 2.040" - 2.060", on both intake and exhaust, both cylinders.
John
« Last Edit: December 19, 2018, 06:15:42 PM by johnsachs »
Logged

MCE

  • Guest
Re: Easy way to check spring spacing for bigger cam
« Reply #3 on: January 10, 2019, 06:43:21 PM »

Protrusion on S&S' stuff is usually very consistent. (Usually within a few thousandths)
Logged

prodrag1320

  • AMRA & AHDRA P/D record holder
  • Vendor
  • Elite CVO Member
  • *
  • Offline Offline
  • Posts: 917
Re: Easy way to check spring spacing for bigger cam
« Reply #4 on: January 11, 2019, 06:33:29 AM »

why would you have to even remove the cylinder? just try not to disturb it when removing the head.as far as springs go,the head should be removed as valve to valve & valve to piston should also be checked,not just coil bind

MCE

  • Guest
Re: Easy way to check spring spacing for bigger cam
« Reply #5 on: February 25, 2019, 04:35:29 PM »

V-V should be checked. (Good point)
Logged
 

Page created in 0.134 seconds with 24 queries.