Valve Springs recommendation

[50Panhead]

Well if it a worm or Snake I wish it would jump out and bite me. Still have not heard from the Machinist.

Lets see if this works better.

[Adam M]

You want to run FLH springs , I wouldn't want to run that kind of poundage on that 1950 cam bushing. If you have a stock cam , there's no reason for that much closing force on a stock machine. IMO
Adam

[50Panhead]

You want to run FLH springs , I wouldn't want to run that kind of poundage on that 1950 cam bushing. If you have a stock cam , there's no reason for that much closing force on a stock machine. IMO
Adam

Bike was rebuilt in 1975. It has been bored 40 over has 5/32 oversize valves, Cams and push rods were changed eliminating the hydraulic push rods. All new bearings. It was a total rebuild and I remember being told it was built with FLH parts. last weekend I went to the Dealer that rebuilt it and ask if they still has service records as I wanted to see if they changed the valve springs and the kind of cam they put in it. But they had destroyed all records paper records years ago.

[50Panhead]

I got a call from Jerry Jones the Machinist who has the heads. He tested the valve springs and the exhaust springs are shorter (free length) then specifications and weaker. I'll get a new set of springs ordered and cross my fingers that this solves the problem.
Oh yes he also said that the Exhaust springs showed signs of polishing between the springs and Collars a sure sign of springs spinning which he said is a good sign of springs being too weak.

[50Panhead]

Up Date:
Things have gotten kind of crazy for a while and I have not been able to work on my 50FL. Now that I have been able to get back to putting it back together I find my rear intake nipple leaking when I did the soap bubble test. During the winter I custom made a new intake nipple for the front head only. The rear nipple sealed up good (No Soap Bubbles) in the test. Why fix something that ain't busted. Well I guess during all the dis-assembly and installation of new valve springs things changed. Rear Nipple leaks bad. So I'm back to making a custom Oversize nipple for the rear cylinder.
While I'm at it can anyone tell me the Minimum and Maximum space between nipples and manifold. Right now I'm looking at 0.50 space when I hold the manifold between installed nipples. Thats 0.25 on each side if centered. Can this be reduced? If so How tight can I have it and still have room for expansion.

Thanks

[T. Cotten]

50Panhead!

Please remember that the cylinders are angled away from each other, so heat expansion will always widen the gap.
.025" is quite minimal; Most are more.

I have a local '50FL running great with an EL manifold. Now that's a gap!

....Cotten

[50Panhead]

I custom made a couple new intake nipples and I have the best fit installed. I used a small amount of J B Weld in the location where the O rings went on the Colony nipples just for extra insurance when I installed the one I made. If this old bike was a Girl I'd say she is Jealous of all the other bikes I have and she is pissed off making my life difficult. I hope I have spent enough hours with her that she will run like she used to when I'm finished putting her back together.
First photo is ready for Soap Bubble test. Second Photo shows front nipple just sightly longer reducing the distance between nipples. That was my first one replaced. I should have made it about one thread shorter. Third photo is of one of my first machined nipples. I turned it into a Tap so I could use it to clean up the threads in the head. And the forth is the newly machine nipple compared to the Colony Nipple. Mine is machined to take advantage of all the threads in the head and they are 0.10 OS to take up for the wear from all the Slop. The Tap I made is also 0.01 OS. It took several attempts to get a good fit. But I'm happy with the results. Tomorrow when the J B Weld cures out I'll test for Leaks. Fingers Crossed.
100_8039.jpg100_8040.jpg100_8043.jpg100_8045.jpg

[50Panhead]

I got her all back together the other evening. This evening when I got home from work I put the battery back in her and filled her up with 91 Oct. A couple kicks to prime and a couple more she fired up. I let her warm up and adjusted the low speed jet and idle. I took her out for a ride (20 Miles) At first she coughed and spit back through the carburetor. I adjusted the low speed again. Well I think she has forgave me. I turned around at 10 miles and she never cough once. Ran good .Thanks you Sweetheart.
100_3400.jpg

I think the problems was a combination of several things. Valve springs Weak, Improperly shimmed, Rockers binding from being over torqued.
Thank to everyone. And especially Cotton for his peek manifold Seals and help with my carburetor.