decomp mod

30 replies to this topic
  • grayracer513

Posted May 12, 2009 - 04:43 PM


Hot cams says not to use synthetic oil for the break in the problem is I only run synthetic does it matter?

I have no idea why any thinking individual would say that, but I do all my break ins with the same oil I always run. That happens to be Amsoil MCF full synthetic.

In general, there are two things you need to observe regarding cam break-in:

  • Use a moly assembly lube. Not gobs of it, just a coating on the lobes. Drench the lifters with your engine oil before you close up.
  • Keep the engine above 2000 RPM for the first 15~20 minutes. Improves lubrication and reduces scrubbing the new lobe surface.

Ideally, you would replace all the lifters, too. You don't have to, but it is the best approach. If any of them look worn or "wavy" on top, get new ones.

  • buzzgrizz

Posted May 12, 2009 - 07:46 PM


all the lifters looked good I guess I'll use the mobile 1 oil that I've always used for the break-in the new hot cams exhaust cam didn't have any of the painted marks on it like in the pictures. So I'm like 90% on how it's supposed to go in.

  • gixxer7500_0

Posted May 13, 2009 - 11:24 AM


sorry never heard of a freeze plug what are they ? im from uk which might explain it

  • grayracer513

Posted May 13, 2009 - 11:49 AM


sorry never heard of a freeze plug what are they ? im from uk which might explain it


  • gixxer7500_0

Posted May 14, 2009 - 12:19 AM



I get ya over in uk we call them core plugs cheers !!!!!!

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  • grayracer513

Posted May 14, 2009 - 06:37 AM


I get ya over in uk we call them core plugs cheers !!!!!!

Core plugs, bore plugs, soft plugs, cup plugs, freeze plugs, frost plugs, Welch plugs (actually a slightly different style, but the name gets used).....

Ain't English great?

  • buzzgrizz

Posted May 23, 2009 - 02:01 PM


finally finished waiting on parts and tools is what took the most time but I got it done today and like the mod so far but now my linkage is locked up:foul: so there goes more money and time not riding. How big of a deal is this linkage issue gonna be? I have a race next weekend maybe I'll be able to make it.

  • grayracer513

Posted May 23, 2009 - 03:40 PM


What linkage? Rear suspension?

  • buzzgrizz

Posted May 24, 2009 - 05:34 AM


the rear suspension linkage

  • grayracer513

Posted May 24, 2009 - 06:47 AM


That won't be too big a deal as long as it all comes apart cooperatively. The swing arm pivot can be a problem if it rusts into the steel inserts in the rear of the engine.

  • buzzgrizz

Posted May 26, 2009 - 06:50 PM


We got everything back together Sunday afternoon, the decomp mod is going to be great and we got the rear suspension all greased up and ready to go. Thanks to everyone for all the great information, it made the project much easier

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