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Popping

154048

Atomic City Boxer
My R100 has recently taken to popping on decelleration. Pulse air system has long been removed.
Does popping and blubbering say anything about my mixture? Too lean or too rich ..or neither?

Thanks
 
usually means too lean, often as result of air getting past some intake seals (carb to head, airbox to carb, etc). depending upon severity, may or may not be a real problem, other than the annoyance factor).
 
My /5 does it on deceleration; not a lot, and no pop, just a bit of "blubber".

I think it's a normal condition. It runs like a champ the rest of the time and my exhaust color is spot on. I just keep the tiniest bit of throttle rolled on when decelerating and it stops.

If it's backfiring, I'd say you need to investigate a bit further; valve adjustment, ignition timing, spark plug insulators, synchronize your carburetors, etc.
 
It is actually more of a blubber or sputter....I'll check various clamps for tightness. Thanks for the replies.

Oh, a funny thing...I just got off my Suzuki DR and took the RT out....It is like piloting a large ship after the quickness of the DR. Of course it is like comparing a can of beer to a fine, aged Merlot...Each has their own qualities..
 
Also make certain you don't have an exhaust leak (loose fitting/clamp) or a hole in a muffler. This causes my R90 to sputter and pop on deceleration. I patched a hole in my muffler to stop it while I wait for new mufflers from Motobins.

I have an R12RT and a DR350 too! I know what you mean. Both are sweet bikes for what they are made to do.
 
Could be the opposite

Throughout all of the airheads I have worked on, a popping is usually due to an overly rich mixture. An overly rich mixture will cause an excess of fuel to make it into the exhaust stroke. Naturally, the fuel gets pushed into the muffler by way of the exhaust stroke where it will then get hot enough to combust or "pop." Run the fuel : air mixture screws all the way in until they barely seat and turn them out 1 and 1/2 turns. This should give you a solid starting point where you can adjust from there.
 
As Airheader13 say but adjust the valves and check for air leaks first. I've found that a properly adjusted air mixture screw will solve this popping most of the time
 
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