$12 Muffler Fix! So proud!

Discussion in '2-Stroke Engines' started by Timbone, Oct 7, 2014.

  1. Timbone

    Timbone Active Member

    Here was my task: stock muffler was toast. Stuffed full of steel wool and capped with a can lid. Broken left ear.

    Left exhaust stud is fine, threads are still good. Right exhaust stud hole holds the remnants of a 6mm bolt and the threads that are accessible are stripped.

    Riding with itch no muffler is not an option. Much too loud and not good for that busy piston!

    i dabbed three pieces - you should be able to see them in the dark photo.

    1) $6 copper male adapter 1/2". I cut about half of the "slip" part off, then ground down the rest to make the 11/16ths up down clearance. I was left with two ears that inserted into the block. Obviously, the 1/2" copper threads stick out towards the muffler. I fabbed a new exhaust gasket and inserted the fabbed copper ears into the cylinder with a nice tight fit.

    2) Made a mild steel bracket with a U-shaped hole to wrap under and hold the copper insert up. Drilled a 6mm hole to match the good exhaust stud that I can still use. Also drilled a small hole on the other side as to allow support piece later. Free.

    3) Fabbed a C-shaped bracket out if a stainless fender washer with appropriate 6mm hole drilling to go over the U-shaped bracket. The U and the C wrapped the copper fitting all the way around. Free.

    4)Bought a $2 electrical conduit fitting - a 1/2" stainless steel coupling with internal threads. With the left exhaust stud holding the gasket and 2 brackets, I threaded the coupling onto the male threads if the copper insert. This brought it all together!

    5) Bought a $5 lawnmower muffler with 1/2" male threads that fit perfectly into the stainless coupling. I have a new muffler!

    6) Final step: attached a long strong spring to the seat tube (using a clamp) and grabbed the hole in the steel bracket with a S-clip. Bam! Good tension!

    The final product us still loud and, yeah, it sounds like a lawnmower, but I am back on the road. And it is as fast and torquey as ever. Commute #11 today!

    I've had more exhaust issues than anything. Those 6mm studs just can't take it. It's good knowing that my remaining stud is carrying a fraction of the weight it was carrying.


    Attached Files:

  2. butre

    butre Well-Known Member

    that's similar to the exhaust system on a lot of utility engines, it should serve you well enough
  3. Timbone

    Timbone Active Member

    Yes, it is serving me very well! Great ride today!

    You would think that with the exhaust straight ahead it might be worse in terms of breathing. Not at all, in fact, there are two advantages: I have an idea of how little this thing pollutes at 100 mph and if my hand gets chilly like they did this morning, I can't reach a hand down for a bit if warmth. :)