Muffler Crank Pedal Clearance

Discussion in 'General Questions' started by ezrider, May 23, 2016.

  1. ezrider

    ezrider Member

    Some say its s good idea to bend the muffler pipe with a hammer. Don't know about that. Anyway, I'm sanding off about 1/8" from the crank pedal to give it some space.

  2. Frankfort MB's

    Frankfort MB's Well-Known Member

    Do you have access to a vice and torch? I Wouldn't sand away your pedal since most of your weight is on it, I also wouldn't want to scratch up a shiny new exhaust
  3. ezrider

    ezrider Member

    No doubt a torch could help it bend a bit. Just what is the recommended space clearance between the muffler pipe and crank arm pedal ?
  4. Steve Best

    Steve Best Well-Known Member

    All these darned pipes are in need of a bit of a bend to work EZrider.
    Make sure it clears not only the pedal but your toes too.
    I had mine off and on a dozen times before I was happy.

    This is a FAIL:
  5. erider

    erider Guest

    That wicked muffler pipe looks like its been through a glass blower. Talk about fitting a square peg into a round hole.
  6. 45u

    45u Active Member

    Is it a stock muffler? I did not have any problems with my stock muffler.
  7. Frankfort MB's

    Frankfort MB's Well-Known Member

    I've had minor clearance issues, nothing a good torch couldn't fix
  8. skyash

    skyash Active Member

    I grind the back off the crank arms more then enough metal to hole you up some times I take 5mm off if you cold bend the pipe it will kink some times a fater gasket on one side will move the muffler now I just cut and weld it where I like
  9. Hello Moto!

    Hello Moto! Active Member

    I had one kit that I had to bend the muffler and another that I didn't have to touch. I bent the first one by holding the muffler in a vice and heating it up with a map gas hand held torch. Once it was good and hot it was pretty easy to bend it how I needed. One thing to keep in mind is to try and bend it without putting any creases in the tube. The goal is to just give yourself the clearance that you need and not a whole lot more.
  10. Island Racer

    Island Racer Member

    Whauwwwww fail or not but that's nice .....

  11. danlandberg

    danlandberg Member

    If they would weld the muffler to the header pipe at a different degree, there would be no peddle to muffler clearance problems, but on some frames there may be a down tube to muffler problem. I have ran into two builds with peddle to muffler problems. I changed the crank arms from another bike which had a slightly wider peddle stance. One build the header/muffler pipe wouldn't even line up with the cylinder with out hitting the down tube. Quality control failed to catch the defective muffler before packaging. (I thought it strange for GRUBEE). If you have a three piece crank it should be easy enough to swap arms.
  12. butre

    butre Well-Known Member

    you can take a chainsaw file to the stud holes in the pipe and rotate it a hair. an eighth of an inch in the holes equates to a pretty significant movement where the crank would hit
    Timbone likes this.
  13. Hello Moto!

    Hello Moto! Active Member

    You could also saw off the muffler and have a 3" straight pipe lmao!
  14. KCvale

    KCvale Motorized Bicycle Vendor

    All I have to do in most cases is just use a drill to elongate the pipes flange mounting holes so you can turn it, I even have a shop name for it, 'reamy-reamy' the pipes holes ;-}

    It won't always work, but it's easy to do and won't hurt a thing.
  15. danlandberg

    danlandberg Member

    I've inlongated the holes in the flange on a couple of builds, it helped, but not always cured the problem. They just need to rejig to change where the muffler is welded to the header pipe. The muffler inlet is off center. We all don't have a welder handy to do it right.
  16. KCvale

    KCvale Motorized Bicycle Vendor

    So true.
    That however brings getting an X-chamber exhaust in to play...
    If you have to speed money on the exhaust, might as well get a performance boost from it.
  17. danlandberg

    danlandberg Member

    So true. I agree 110%.