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Latest post Sun, Apr 8 2018 5:30 PM by andy2175m4. 35 replies.
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  • Thu, Apr 5 2018 6:50 AM In reply to

    • FX
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    Re: where is this loud noise in sporster engine ?

    Andy, also send the noise to sfranta, and Ironhead...

    FX

    Don't force it, get a bigger hammer.

  • Thu, Apr 5 2018 9:04 AM In reply to

    • Ironhead
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    Re: where is this loud noise in sporster engine ?

    Andy - when you had things apart, did you mic the lifters & lifter blocks?  I have seen lifters that were worn (front to rear) which "flopped" ahead when they were nearing TDC - had to replace the lifters but the blocks were OK.

    What grind of Cam do you have (you probably haven't had the cam cover off).  When I went from PB cams to PB+ cams on my '77 I noticed a bit of difference. 

    My '77 is considered quiet but the engine makes more noise (at an idle) than the exhaust on my '96 FLHR.  It is a solid lifter engine, based largely on a 1957 design, which will never be as quiet as a hydrolic lift engine.

    I just sent you a PM with an email address.

     

     

    The first tool out of the box should be the "book"  Geeked

  • Fri, Apr 6 2018 10:52 AM In reply to

    • Ironhead
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    Re: where is this loud noise in sporster engine ?

    Andy - I got the emails you sent me but my work email service blocked the attachment.

    So, you found a badly seated valve on the rear head from a (previous owner) water leak into that cylinder.  If the valve isn't closing correctly, that could cause you problems.  Is the valve guide steel or bronze?  If it is steel, I would suggest getting bronze ones installed while it is apart.

    If stock, the seats are part of the casting of the head - not a replacable steel insert like the big twins.  I have seen steel seats advertised (not much money) that would require maching the head to be able to install the seat then ground to fit the valve.  I have also seen valves advertised which are 1/16 larger diameter (at the seat) to assist when the there is insufficent seat (or trying for a little more air flow).  SFanta should be able to source these valves if they are needed.

     

    Hope this helps

    The first tool out of the box should be the "book"  Geeked

  • Sat, Apr 7 2018 1:23 AM In reply to

    • andy2175m4
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    Re: where is this loud noise in sporster engine ?

    I aggressively cleaned the head, lapped the valve a bit, and put the top end back together, but did not make any effort to put the lifters and push rods back in where they came from, it was just a random reassembly.

     

    I did run the engine but only for a moment,  I dont think the neighbors appreciate a sportster running with  open straight pipes after dark,  so I cut it very short.   It did sound different though, the clanking seemed to be different, maybe,  but the lifters are so noisy and the pipes are so loud its hard to tell.  I  will check it out again tomorrow when the neighbors are awake.

     

    By the way I ordered an XLS / cafe racer x-type header so I can put the original XLS crossover exhaust back on,  ie. a dual exhaust,  one on each side,  with an actual muffler on each side,  so   I will be able to run it and drive it thru the neighborhood at just about any time,  and not wake the dead.

     

     

     

  • Sat, Apr 7 2018 2:07 AM In reply to

    • Ironhead
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    Re: where is this loud noise in sporster engine ?

    andy2175m4:

    By the way I ordered an XLS / cafe racer x-type header so I can put the original XLS crossover exhaust back on,  ie. a dual exhaust,  one on each side,  with an actual muffler on each side,  so   I will be able to run it and drive it thru the neighborhood at just about any time,  and not wake the dead.

    the siamese exhaust?  I fitted one of them on my '77 with custom mounted Bazani fish-tail slipons

     

    The first tool out of the box should be the "book"  Geeked

  • Sun, Apr 8 2018 5:30 PM In reply to

    • andy2175m4
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    Re: where is this loud noise in sporster engine ?

    Yes, the siamese exhaust header, the original config of the XLS, with 2 stock evo sportster mufflers. 

    I also sent an email to J&P Tech support, and got this thoughtful reply from one of their guys:

    "Those motors are noisy naturally. nature of the beast. you may be able to quiet it down a little bit by running it on the tight end of the scope...but itll never be quiet. they chatter. didnt matter how much i adjusted mine or rebuilt over and over and over..it was always noisy."

    Such is the life of an Ironhead i guess,  a noisy motor no matter what.  I used the stethoscope and the noise is still loudest in the top end of the rear cylinder, but I have checked every part, even the valves, shy of pulling the crank, and every part is in spec, and looks fine.  So I guess it's the nature of the beast. 

    Maybe I will stick rubber plugs between the fins like on my old Yamaha IT 400 2 stroke, that quiets down the ringing a lot.

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