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Can I degree my cams if I don't know cam specs?

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    Can I degree my cams if I don't know cam specs?

    My 1982 GS1100E has some aftermarket cams in it from back in the day and I have no idea what the specs are. They say V.H.R. on them and so I emailed vance & himes but they no longer carry the specs on those old cams. They allready have adjustable slotted sprockets on them and just looking at the position of the bolts in the slots you can tell they are retarded almost all the way. I want to degree them because the engine acts like it is missing on two cylinders at about 2800-3500 rpm under low load cruising about 40-45 mph with about 5-8% throttle. I have ruled everything else that could cause this problem out. I have a digital A/F ratio gauge and am running good A/F ratio across the board.

    It also has brand new Dyna ignition and I just rebuilt the motor 2400 miles ago. It is an 1198 big bore with several go fast parts making 122 whp and probably about 130 now that I have it tuned better. I will also say that with the air filters off, you can see air/fuel mixture being sprayed out towards the air filters probably due to too much cam overlap?? And this might cause the popping I have? The weird thing is the bike runs great even in that RPM range but it only runs bad like I said under low load. I just ran a 10.62 at the strip so she runs pretty good.

    So, without knowing the cam lift, duration, etc., can I still degree these cams? I ask because all the research I have done says that when you degree your cams you should refer to the manufacturers cam card for their specific degree #s which of course I don't have
    . Can I just degree them to the factory GS1100 specs and be close enough? Any advice would be appreciated. Thanks!

    #2
    You should measure lift and duration and work from that. Most good engine builders never look at the spec sheet from the cam manufacturer.
    '20 Ducati Multistrada 1260S, '93 Ducati 750SS, '01 SV650S, '07 DL650, '01 DR-Z400S, '80 GS1000S, '85 RZ350

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      #3
      Originally posted by Paul.S View Post
      . Can I just degree them to the factory GS1100 specs and be close enough? Any advice would be appreciated. Thanks!
      It depends on the grind on those aftermarket cams. If the center of max lift is the same as stock and just duration is extended then yeah probably. But if the lobes have been off set either way, you might make the problem worse. That is why you need the mfg. specs. or failing that, a set of stock cams with which to compare. If you can't/don't want to do either of that, the next option is to walk them back a half a degree at a time and see what that does.

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        #4
        I might even consider purchasing a new set of cams for it. They only sell a few from Dynoman performance and the ones for street/strip use say you need hardweld rocker arms and the oil bump has to be ground off of the rocker arm. And of course stiffer springs must also be installed. Well the previous owner said it had performance springs in it and I am sure it does becsuse I have had it up to 13,000 rpm on accident before. But how do I know if I have hardweld rocker arms? Can I tell just by inspecting them up close?

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          #5
          I am a Web dealer & used to work at V&H. Call me at 714,356-784five & I will help you. If the cams are Vance & Hines, the cam part #s are under the cam sprockets. V&H cams were made by Web.
          Ray.

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            #6
            Originally posted by rapidray View Post
            I am a Web dealer & used to work at V&H. Call me at 714,356-784five & I will help you. If the cams are Vance & Hines, the cam part #s are under the cam sprockets. V&H cams were made by Web.
            Ray.
            Awsome Ray! I will go ahead and pull the cams out and give you a call with the #s.

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