2012 fatboy engine Vibration above 2500 rpm

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  • xlr8it
    xlr8it
    11 years ago

     I have just fitted V & H big radius and have a strange problem, I get a very unpleasant vibration through the whole bike (can feel it in the boards, handle bar & seat) when the engine is above 2500 rpm, it is more pronunced when the bike is under load.

    I had V & H slip ons before and did not have this problem.

    Went for a long ride yesterday (600km) and it became worse as the day progressed. 

    The bike has V&H fuelpak and Hypercharger

    Any help would be greatly appreciated.

     

     

  • paulybronco
    paulybronco
    11 years ago
    Compensator.
  • Ando
    Ando
    11 years ago
    Could be the crank has shifted, strip the cam chest and measure crank runout, that would be the first thing I would do
  • houli
    houli
    11 years ago

    Just put the bike back to what it was before you had problems, then start troubleshooting.................don`t go fkning around with it in its current state, you know something is wrong, check the basics first.

  • paulybronco
    paulybronco
    11 years ago
    good call with the crank suggestion. Will be a warrranty job if it is so dont touch it!
  • xlr8it
    xlr8it
    11 years ago
    The bike has done 7k km and is under warranty , what is a compensator?
    is the compensator or the crank a big job
  • paulybronco
    paulybronco
    11 years ago

    how hard do you rev this bike?

  • xlr8it
    xlr8it
    11 years ago
    i do not often go over 4000rpm
  • paulybronco
    paulybronco
    11 years ago

    My pick is a compensator issue then

  • the_mongrel
    the_mongrel
    11 years ago

    Hmm... I have the same setup mate, and mine has vibed hard since the day I rode it out of the shop! Unless I am wrong, I would have thought it's the 96 cubes (103 in you case) pounding away beneath your arse!!

    Does it sound like it's vibes as the pistons fire? As in, is it in time with the bike, or is it something like a bad wheel balance??

    Don't forget, these engines are not rubber mounted like the Dynas.  So there will be some vibes.

  • Rooster
    Rooster
    11 years ago
    If you are going to check basics, before you go pulling the pipes off check that the header nuts are properly torqued up, the flange ring is seating properly and not pushed out past/around the header flange.

    Also with those big radius pipes make sure the baffles are tightened up properly. A loose baffle will vibrate at a certain rev range, and it only needs to be a little loose. I had a loose baffle and thought that the motor was pinging its head off. They are usually secured with one allen head bolt through the pipe and into the baffle, located at the most hard to reach spot.

    Good luck.
  • xlr8it
    xlr8it
    11 years ago
    Thanks guys, will check the pipes.

    Mongrel the vibes are in time with the piston fire, but it did not do it with the factory headers and V&H slip ons that i had on the bike for the last 6000km, only with the Big radius and became worst as the day went on to the point of being really unpleasant above 100 kph
  • the_mongrel
    the_mongrel
    11 years ago
    Hmm... Not sure mate. I know the pipes bolt directly to the frame, so maybe now you are feeling it more.

    Maybe try and find someone with the same pipes and ride theirs to compare!
  • AJ56
    AJ56
    11 years ago
    I would be looking at the pipes. I don't think it would be the compensator as it would be consistent throughout the rev range. ( Get a long screw driver and have a listen on the primary, you should hear if it having any issues.) Do those pipes have heat shields? If they have make sure they are not touching something and are done up tight). Also check the torque on the header bolts. They have a tendency to come loose.. Did you replace the flange gaskets when you changed the pipes? If so the gaskets may have compressed enough for the pipes to come loose on the run.
  • the_mongrel
    the_mongrel
    11 years ago
    Ok... I went for a ride today and had look and feel of my ride and I can tell you that in 5th gear pulling hard, I can't see shit in my mirrors because of the vibes.

    Once I drop to 6th, it smooths out a bit, but again under hard pulling the mirrors are a mess - so plenty of vibes, and it's always done it.

    I haven't ridden anyone else's bike to compare - have always thought it was normal.
  • the_mongrel
    the_mongrel
    11 years ago

     Nope!  I am using chain not gear, so didn't see the need.

    AND if it was out - what the fuck was I going to do about it.  LOL!!

  • woodybill
    woodybill
    11 years ago
    I have same vibration problem mainly foot boards.fitted v/h short shots.after 50km ride feet keep viabrating for quite some time.I had no vibration before fitting pipes.
  • xlr8it
    xlr8it
    11 years ago
    Thanks for all the suggestions,
    I am going to fit the original pipes back on and see how it goes,just waiting for new exhaust gaskets.

    I will let you know when its done.
  • woodybill
    woodybill
    11 years ago
    xlt i am going back to original pipes to.went for ride about 120km on saterday could not hardly walk on sunday.i was told the vibration is like a solid workout.could you tell me what the slip ons sound like /against the vance and hines short shots.you say you had no vibration with the slip ons .
  • the_mongrel
    the_mongrel
    11 years ago

    Hmm.. Mine is not bad enough to want to swap them out, so must be something else.

    Pitty you were not closer mate - You could have a ride on mine to see the difference.

    Happy to maybe meet you in the middle.

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