Fuel question.
I have Screamin eagle 211 cams and their big bore kit on my 05- 88 twinky. Been chasing deceleration pop. I am aware of air leaks. Just dawned on me to ask if the stock brass inlet 90 and the 1/4" fuel line is enough flow. Could these 10.25/1 pistons be needing more fuel flow? Rejetting didn't work. Short pipes no baffles. Waiting on a complete gasket and rebuild kit to eliminate and refreshen what I believe are factory parts through and through. Minus my build.. Heads were sreet ported, as well. Only two things that make sense. Air and fuel. Guess I should look up how to check the timing while I'm at it....
STHH....

 

Is the decel pop something new? If not, short exhaust pipes are notorious for being the cause.

 

It's the pipes. If you make it rich enough that the actual exhaust won't explode (pop), your lubrication will be gasoline.

 

Popping on deceleration is a sign that your air/fuel mixture is not correct. The usual cause is running too lean which causes the exhaust to get hot to the point of igniting any unburnt fuel in the exhaust system itself. It can happen from a too rich mixture, but it is much rarer.

It's your call as to whether you want to tune your bike to do this. But in either situation, it's a sign of on improperly tuned bike.

 

The 90 degree inlet is NOT your issue

 

Short pipes, no baffles and poor tune will do it all the time.. get a better exhaust and tune..