Powerloss and backfiring in left cylinder (video)

Niels Mouthaan

XS650 Member
Messages
9
Reaction score
1
Points
3
Location
Amsterdam
Hi guys,

I have an XS650 from '83 with electric ignition. A few months I did an annual check and corrected valves and timing. Recently I start noticing that my left cylinder is backfiring a bit (especially when running idle or when decelerating). Also when holding my hand behind the exhaust I felt that the left cylinder is simply not running as smooth as the right one. I switched spark plugs and spark plug cables and nothing changed. While riding I don't really feel that it's running bad. Always starts, always runs. However, when I remove the spark plug cap of the right cylinder it stops running almost instantly while when doing this with the left cylinder, I barely notice a difference.

I recently bought a carb sync tool and noticed that they carbs are not synchronised. See
for a video recording (left gauge is left cylinder). However, I also noticed that when releasing the gas throttle, the pressure of the left cylinder is not dropping like the right cylinder. Based on this, I doubt whether this is just a synchronisation issue or something else. What do you guys think?

Thanks - Niels.
 
Back
Top