exhaust explosions?

Were do they comme from these explosions? Carburator, she's clean now?
Many big motorbikes have the problem to..... but I'm only the little guy on the block.... .
What to do?
The bike does it with the old exhaust and the new exhaust?

Is the exhaust clamped tight at the barrel end and is the gasket any good! Are there any holes in the exhaust? This can usually be the cause of backfire on de-acceleration. sounds pretty good if its on a bigger bike, and in extreme cases can cause flames to shoot out of the end of the exhaust

All the best Si

Thank you Simon... but with bought the exhausts..... I've read on an other forum.... lack off air?

I want flames out of my exhaust!
My current exhaust is a straight through pioe with no baffles, sounds great, sorry I know this doesnt help.

White wrote:Thank you Simon... but with bought the exhausts..... I've read on an other forum.... lack off air?

Possible.
If the mixture is too rich, an amount of unburnt fuel travels trough the exhaust.
The heat of the exhaust causes the fuel to explode.

Other options:
- wrong ignition timing
- too much air
- leakage

May sound cool, but this can burn your outtake valve!

About 30 years ago I used to drive a Leyland Sherpa van for work. You could drop down from 4th to 3rd gear, turn off the ignition, coast for 50 yards then turn it back on and it would let out the loudest backfire you ever heard, it was great fun. See a whole streetful of people jump at the same time, hillarious. Until I dropped a valve doing it

Simon, You're wright I think. I did have a look at the so called gasket and yes.... it was like a bit broken it was obstructing the inlet off the exhaust..... The problem is not solved but the explosions, backfires our less frequent now, he's running without a gasket now.... The bike does go a little bit faster to....
I must say this little bike hasn't being running since a good od 10 years...
But he's on the road again....

the problem is no longer... thank you my friends

What did you do to cure it ?