Barbling and backfiring

[Scoote]

I have a 2001 650s and the bike has developed this 'condition' over the past few months. Acceleration is ok although I am sure I can here air being drawn in. When I let the revs off it pops and bangs like a goodun, it doesn't always backfire but always grumbles. I have removed the exhaust and have found a very fine 20mm crack in the lower pipe gasket. Is that enough to cause this problem??? Have also removed the tank and checked around carbs but didn't find anything obvious. This is really annoying and as much as the twins do grumble as you slow I had 15 months of nothing so it must be fixable. Help me please! :?

[TSM]

If there is any gap in the seals onto the exhaust ports then air will be drawn in and will ignite the exhaust gases.

[carlos]

I'd say that crack is the probable culprit. It's a similar situation to when fitting an after-market exhaust and not sealing it correctly, you usually get some (nice) pops and bangs and even the odd flame :D

[Stu]

And the problem is...? :roll:

[Sid Squid]

What you describe is the common symptoms of an exhaust leak.

[Ter]

And the problem is...? :roll:


:D

I'll go loosen my pipes then!!!

8)

[james160987]

meh mine does it, i ent worried, i know its prob blowing a tiny bit, but the sounds are good

[lew893]

I don't see a problem? mine does it and has big blue flames when rolling off the throttle love it!! gets people to move too!!! :twisted: sometimes makes me jump though if I'm tired and not expecting it!!!! :lol: