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Discussion Starter #1
I just tore down my motor to change headgaskets and discovered that my FST Stage 3 cams are pitted again on the intake lobe of the front cam. The rear cam looks fine. I'm disappointed b/c I previously had flaking/pitting issues with these same set of cams about 1.5 years ago. At that time, I had them rewelded at Web Cams and then I sent them off to be cryogenic treated (hardening process using extremely cold temperatures).

As a side note, I'm not sure what I'm going to do now. Should I try to get these cams repaired once more or just toss them and try a different set of cams??? My FST 800 pistons and the cylinder walls look good, so my only problems are with the cams and headgaskets. Anyone have any good suggestions for me?
 

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Post some pics..
Did you replace the rockers at the same time you had cams repaired?
What did you set the valve lash at after they were broke in and did they stay that way after some riding?
 

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What kind of performance issue does it cause to have flaking and pitting? Seems to me it would be more cosmetic.
 

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If the rocker is not actually wearing into the cam lobe, I would just keep running it.
 

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The issue is the cams themselves, the weld is sprayed on and sometimes it just pits and flakes off.

Soon there will some billet cams coming from Fundy.
 

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if the issue is the cams themselves i would be buying some cams elsewhere. 400+ dollar cams should last more than a year.
 

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Discussion Starter #7
There appears to be a tiny discoloration on the rocker arm pad where the pitted lobe rubs, but it appears to be cosmetic only and does not feel like a scratch/scar. In fact, all of the rocker arm pads still feel very smooth, so I have never replaced them and don't think they need to be replaced now.

I believe that my valve lash was always set to .004 and .006. They usually need very little adjustment (if any) whenever I've checked them...as I recall, 2 of the 4 valves usually need to be loosened a tiny bit, but the other 2 are usually spot on.

I've noticed zero performance issues with these cams from day 1...the only reason that I found the pitting/flaking (both times) was b/c I tore down the motor for head gasket replacement.

As far as I know, all of the well-known engine builders use the same cam manufacturer (Web Cams) to produce their cams...so I'm not sure if I'll have better luck with a different set of cams or what.

Any other thoughts?
 

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Discussion Starter #9
Thanks for the reply Nova, but my concern is that if I continue to run the pitted cam, then eventually the pitting on the lobe may get worse and eat up the rocker arm pads. Seems the prudent thing to do is to fix or replace the cams before it causes more damage to the rest of the motor. Also, the motor is currently torn down...I'd much rather fix it now than have it cause problems later (in the middle of a racing series).
 

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run good oil and run em... I have pitted cams in 2 of my bikes for years.... hasn't even worn a groove on the rocker arm at alll.
 

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Discussion Starter #11
Thanks Z-mann,
That is the info I was looking for. I didn't know if anyone had actually tried using pitted cams and whether doing so would likely eat up the rocker arm pads or cause other problems. I may just go ahead and re-use my cams...the pitting is very small and didn't seem to scar up the rocker arm pad so far.

Happy trails...:)
 

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I ran a set of pitted cams... just backing up what zmann said.
 

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I believe that my valve lash was always set to .004 and .006.
I thought the Valve lash was suppose to be like .006 IN and .008 to .010 EX?? I have my FST cam last at .007 IN and .009 EX.
 

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run them if the flaking isnt too severe.. my cams had a couple of spots on them when i took them out of the brute to put in the V..
 

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They all get some marks on them.
I wouldn't worry about them unless they are real bad.
They seem to get to a point,then stay that way for a long time.
 

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no sry I'm at .009 on the EX cam and I can't remember what I set the IN on .006 or .007. I was told the flaking/pitting on the cams came from running the valve lash to tight.

When I was told to run .008-.010 on the EX cam I thought for sure it would make all kinds of noise. No my surprise its fairly quiet.
 

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Set your cams .006 IN and .009 EX. You can run pitted or flaked cams if they aren't too severe. I have ran them before with no problems. Run good 20/50 oil during break in. As long as they are not flaked too bad I would run them. Just run your valves alittle looser the you have been. Mickey changed them from .004-.006 along time ago, he said they was way too and that is what was causing the flaking. I honestly don't know I think some of the cams that Webb turns out are not the best. I had one set of cams that I ran during break in and set the valves at 6 & 8 and they flaked within 20 minutes.

Billet cams is what we need for sure. :rock:
 
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