Bob Martin wrote:
"Sylvain VAN DER WALDE" wrote:
I believe that 2 stroke (racing?) engines were greatly improved (over a
narrow revolutions band) by tuning the exhaust.

Not just racing engines - in the 1950s I had a 125cc BSA Bantam.
One day the nut holding the exhaust end-cap on came off and the entire
contents of the exhaust were shot out backwards.

Oh dear. Similar happened to me on a Matchless once, which spat
out its nice *new* chromed downpipe. Needless to say it got run
over. I still picked it up, unfortunately. It was *bloody* hot.


This affected the engine
power output to the extent that I could barely ride back to pick up the pieces.

V. strange pop squeak rattle noise, too, I should think, and bad
language.