Major Backfiring on Deceleration FE501
- Thread starter geoff
- Start date
-
- Tags
- backfiring deceleration fe501 major
a bit of "popping" under deceleration is normal. prob caused by air leaking into the exhaust.(ie not sealed at joins). mine does it every time i ride it, all the time, usually at about the same revs.
if bike has good power and runs/idles ok i wouldn't worry too much about it.
Have Fun
Jeff
if bike has good power and runs/idles ok i wouldn't worry too much about it.
Have Fun
Jeff
Joined Feb 2003
3K Posts | 384+
Escondido, Ca. USA
Geoff:
Make sure your exhaust is sealed good where the silencer joins the header some good hi temp silicone sealant or specially made pipe sealant will work.
Deceleration popping is usually caused by a lean condition as you have described. When you let off the gas suddenly the air/fuel mixyure goes way lean. If you have a Dellorto carb simply going up one or two sizes on the pilot may do the trick. Also raising the needle up by dropping the clip a notch or two will help fatten up the midrange. Lastly I would increase the main jet size if needed.
Some of the newer high tech carbs have circuits that actually richen the mixture on decel (air cut valves). The Dell is a very forgiving carb though and you should be able to get rid of the decel popping without too much trouble.
Make sure your exhaust is sealed good where the silencer joins the header some good hi temp silicone sealant or specially made pipe sealant will work.
Deceleration popping is usually caused by a lean condition as you have described. When you let off the gas suddenly the air/fuel mixyure goes way lean. If you have a Dellorto carb simply going up one or two sizes on the pilot may do the trick. Also raising the needle up by dropping the clip a notch or two will help fatten up the midrange. Lastly I would increase the main jet size if needed.
Some of the newer high tech carbs have circuits that actually richen the mixture on decel (air cut valves). The Dell is a very forgiving carb though and you should be able to get rid of the decel popping without too much trouble.
Joined Dec 2003
587 Posts | 2+
Where ever we park the motorhome, USA
Try a large pilot jet. A 42 would probably be about right if you are in a area of high humidity ( normally around 60%). If your normal humidity is below 45%, goes even larger, 45 or 48 would be a better starting point.
Leave the needle at stock height until you get the pilot circuit right.
Alot of us have found the needle circuit from the factory is rich, in which case, you will raise your clip and lower the needle.
Leave the needle at stock height until you get the pilot circuit right.
Alot of us have found the needle circuit from the factory is rich, in which case, you will raise your clip and lower the needle.
Joined Dec 2003
587 Posts | 2+
Where ever we park the motorhome, USA
geoff said:
Do you have the manual?
If not go to the link for the free manuals (pdf downloads).
The jets are very easy to change. But you will want to look at the manual to identify which is the pilot jet. Basically, remove carb, remove carb bowl, unscrew jets, install new jet(s), make sure 'o'ring gasket is in its groove, reinstall bowl, reinstall carb. 15 minute job.
Similar threads
Register CTA
Register on Husaberg Forum! This sidebar will go away, and you will see fewer ads.
Sign Up
