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I've tried to answer question after question regarding pipes and "Do I need a processor" in this forum. Regarding the installation of pipes, etc., I highly recommend the latest issue of Motorcycle Cruiser magazine. Mark Zimmerman, who writes their "Tech Talk" column, has a very good article all about pipes. It's a very good read.

Now, I've always suggested that one doesn't need the fuelpak with just pipes, but the occasion does arise when one may be necessary in the event that your engine goes lean with just the pipes. Mark addresses this in the article as well. Many of you wonder about the "popping" off of your pipes. Well, I emailed Mark Zimmerman and ask him about the popping and what would be some signs of a lean running engine. Here is his reply to me, sent today.

"Jim,
The popping is the result of the air injection system activating. I have to run my dog to the vet so I don't have time for the full run down. But the short story is that under normal circumstances the AIR injects fresh air into the pipe on the overrun to burn off any residual fuel. If there's an excess of fuel in the pipe during closed throttle operation (coast) the fresh cold air ignites it with a bang, which is what you're hearing. One way to get rid of it is to richen the idle mixture to the point where it's just to rich to burn. Another is through the use of air bypass valves and other trickery, or by removing the AIR system, which is what a lot of guys do.

Symptoms of a lean mixture include - hesitation or poor throttle response during acceleration, surging during light throttle cruising, misfire at high speeds, poor or ragged idle, and hard starting, slow warm ups and overheating. In a worst case you may also encounter detonation (pinging) during cruise or under load, although that can also be caused by things like poor gas, and overly advanced ignition timing.

When a bike is lean it runs better as it gets hot (both engine and ambient temperature), when a bike is rich it gets worse as it warms up.

I hope this is of some small hope, please feel free to continue the discussion,
Regards,
MZ



I hope this answers these questions for some of you.
 

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Thanks, Jimbo! Good info! I'm sure this will settle a lot of those "do I need an intake" threads, if people will take the time to search that is...
 

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So, after reading this I'm wondering.....Do I need an air intake? LMAO.
 
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