I had a chance to pick up a basically new - mounted to a show bike but not actually run - set of Barons Nasty Boyz exhaust pipes last year. Beautiful pipes, love the mounting system and chrome. Love the sound with the steel baffles installed. But, when I close throttle to decelerate at anything above middle throttle I get popping and even the occasional bang! I've tried moving the baffles from about 4" in the pipes to almost the very tip - no change. I've increased the pilot jet from 25.0 to 27.5 - no change. I've adhusted the air bleed screw from 2 turns to 1 1/2 turns to 1 turn - no change. I'm running a Mikuni HSR45 - jetting specs in my profile.

I never had any popping or backfiring with the Vance & Hines Longshots - even with the shortened baffles. While I like the look and sound of the Barons, the popping/banging is rather annoying. Anyone running similar short pipes run into this? Were you able to cure it? Or am I going to be selling these beautiful pipes to someone else?

NJ

i assume you checked for exhaust junction leaks? both to the heads and if there is junction in pipe?

I would check the usual: air leak from carb to heads? coasting enricher, if has one? leaky junction in exhaust?

Orthogonal wrote:
i assume you checked for exhaust junction leaks? both to the heads and if there is junction in pipe?

I would check the usual: air leak from carb to heads? coasting enricher, if has one? leaky junction in exhaust?

No junctions, just 2 short pipes - much like the V&H Short Shots. New exhaust gaskets at heads. Haven't checked intake manifold since I ported and installed it years ago - I'll look there next.

I have stubbies on mine. they do fine with baffles but rap like a stock car without them...my carb is set up a bit different, I have a 165 main and run the needle on the 3rd from blunt...Your running a bigger main but the needle is set deeper so things even out somewhat...I guess...

Flashback wrote:
I have stubbies on mine. they do fine with baffles but rap like a stock car without them...my carb is set up a bit different, I have a 165 main and run the needle on the 3rd from blunt...Your running a bigger main but the needle is set deeper so things even out somewhat...I guess...

The Yost Power tube made jetting a little different than a regular HSR. Curt worked with me on this setup. I'm thinking of trying a 30 Pilot to see if that helps. Mikuni simply replied that popping and snapping are to be expected with a high flow short pipe system like mine.

I'd like to get rid of the popping altogether if possible.

yea, i hear ya about the popping. trying to get mine to stop recently. i think mine is the coasting enricher so i ordered the cover and diaphram. we will see.

is there something equivalent to coasting enricher/cover on your model carb? mine had crack then hole in it.

Orthogonal wrote:
yea, i hear ya about the popping. trying to get mine to stop recently. i think mine is the coasting enricher so i ordered the cover and diaphram. we will see.

is there something equivalent to coasting enricher/cover on your model carb? mine had crack then hole in it.

Nope...

Orthogonal wrote:
i assume you checked for exhaust junction leaks? both to the heads and if there is junction in pipe?

I would check the usual: air leak from carb to heads? coasting enricher, if has one? leaky junction in exhaust?

Get a stick of incense (a lit cigarette will work but the incense stick is longer) and slowly wave it all around the exhaust flange with the bike running. If there is any leak the incense will pulse with the engine. Best way to check for an exhaust leak and it smells groovy!

txulrich wrote:
Orthogonal wrote:
i assume you checked for exhaust junction leaks? both to the heads and if there is junction in pipe?

I would check the usual: air leak from carb to heads? coasting enricher, if has one? leaky junction in exhaust?

Get a stick of incense (a lit cigarette will work but the incense stick is longer) and slowly wave it all around the exhaust flange with the bike running. If there is any leak the incense will pulse with the engine. Best way to check for an exhaust leak and it smells groovy!

I'll give that a go!

Do like Joe said and look at my jetting setting. I have a 1700 with Bub Stubbies and they don't pop even with a torque tube that is straight thru. I also have the HD yost tube setup and you are too fat on the main jet for a 1600 with a 185 main. I am running a HD 170 main in my 1700 so I would roll the main back to a 165. Mikuni says in their tuning to use about the same size main that you used in your CV carb. Besides the main is easy to change. May need to play with the needle little too. I may have some other needles that you could try I had the whole set at one time. If ya can't get it I will sell you my bike for a price.