Timbone
Well-Known 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.
timbone
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.
timbone
