Ironhead A place to talk about Ironheads.

Valve springs

Thread Tools
 
Search this Thread
 
  #1  
Old 03-22-2008, 09:21 PM
72 chopper's Avatar
72 chopper
72 chopper is offline
Novice
Thread Starter
Join Date: Nov 2007
Location:
Posts: 19
Likes: 0
Received 0 Likes on 0 Posts
Default Valve springs

I have a 72 iron head motor in a chopper. It has S&S 4 5/8 stroker fly wheels, 20 over S&S pistons, Andrews Y grind cam, I belevie is has a .425 lift. Runs like a raped ape, but her is the problem. Getting it started, it eats kicker arms, Kicker shafts, right legs, and ankles, electric starters dont last long either, eats the splines right off the shafts. All ways thought that all the parts and knees were just offerings to the speed gods, but then I was talking to a bike builder in daytona he said something about i may have coil bind on my valve springs. Told me to try the stock valve springs. I am curently running .500 lift springs. Is this what is causeing the motor to turn over so hard. I am currently running compression releases to aid in starting
 
  #2  
Old 03-23-2008, 04:39 PM
thefrenchowl's Avatar
thefrenchowl
thefrenchowl is offline
Advanced
Join Date: Jul 2006
Location:
Posts: 50
Likes: 0
Received 0 Likes on 0 Posts
Default RE: Valve springs

Hi 72 Chopper,

Lift off the back wheel, get the bike in 4th gear, undo spark plugs and spin rear wheel by hand, you'll then soon find out if you're got some tight spots in there that would indicate coil bind...

On the other hand, most strockers should be fitted with cams that give a lot of inlet closing angle, slow down compression to help starting with kicker. Don't know the Andrews Y grind, maybe it's like that already? Check with Andrews about the degrees ABC for inlet closing... 60 degrees or so should be OK IMO...

Patrick
 
  #3  
Old 03-28-2008, 04:55 PM
SportsterBob's Avatar
SportsterBob
SportsterBob is offline
Club Member
Join Date: Feb 2008
Location: Norfolk, VA
Posts: 18,575
Likes: 0
Received 4 Likes on 4 Posts
Default RE: Valve springs

Instinct says that if your valve springs were binding you would have bent a pushrod or worse by now......just for ***** and grins, check your ignition timing....If it is too far advanced it will be a bear to start even with compression releases......4-5/8" stroke with 3-3/16" bore with +.020" O.S. puts you at 74 CI.....Now that is a SERIOUSIronhead! Not for the faint of heart and one helluva beast to start! Ride On!
 
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Manfire
Engine Mechanical Topics
12
02-09-2018 10:25 AM
harleycharlie1992
General Harley Davidson Chat
5
08-27-2014 08:22 AM
Pinetop
EVO
22
06-06-2014 10:15 PM
BadPiggy
Exhaust System Topics
7
08-26-2007 08:56 AM
sporty79
Ignition/Tuner/ECM/Fuel Injection
13
08-17-2007 12:15 AM



Quick Reply: Valve springs



All times are GMT -5. The time now is 05:44 PM.