Z4040 muffler showing large dent from sidecase explosion. Note hoseclamp and metal tab over first rivet hole. Rivet also failed in second hole, which is the gas jet source that burned through the sidecase wall. Total time from rivet failure to sidecase burn-through was about 20 miles, so say approx. 15-20 minutes at highway speed.

Z4040 muffler showing large dent from sidecase explosion. Note hoseclamp and metal tab over first rivet hole. Rivet also failed in second hole, which is the gas jet source that burned through the sidecase wall. Total time from rivet failure to sidecase burn-through was about 20 miles, so say approx. 15-20 minutes at highway speed.