Baffles in straight pipes? Any tips?

[1982fxr]

Stock exhaust on my 95 dyna sucks.  I want it louder but not stupid loud.  I'm probably going to get the Ultima 40" 1 and 3/4 slash cut drags.

I've never messed with baffles before.  Which style keeps the classic sound the most?  The long thin ones?

Any thoughts or tips?

[Tynker]

Drag pipes never sound good(deep). The bigger the can(muffler) the deeper the sound, as a rule.

[Hossamania]

If you're looking for the classic sound of drag pipes, put a 1/4" bolt through each pipe about 2" from the end. It will break up reversion and help them run slightly better.

[Burnout]

Or a lollypop and you can rotate it to "tune" it.

"Baffles in drag pipes is like trying to fart around a cork."

Best anti-reversion is a cone, any returning wave is constricted and effectively blocked, without affecting the incoming wave.
It won't affect the incoming wave because it has expanded and slowed down and is at a much lower pressure level than the incoming wave/flow.

[nibroc]

If you're looking for the classic sound of drag pipes, put a 1/4" bolt through each pipe about 2" from the end. It will break up reversion and help them run slightly better.

.....................what him said^^^^^^^^^^^^^^^^^^^

[Ohio HD]

Make a lollipop from an eye bolt, a washer and a couple of nuts. Tack weld the washer into the eye bolt.

Adjust the angle of the lollipop to just break up reversion that causes exhaust fouling of the inlet fuel charge when the intake and exhaust valves are in overlap.



[attach=0]

[1982fxr]

I made lollipops on my previous shovel, made a difference for sure.

Maybe I'll try these guys version.  Everyone seems happy with them.  I guess the cupped thing is the improvement.

https://www.dkcustomproducts.com/choosing-the-right-size-thunder-torque-inserts.htm

[Ohio HD]

If you want cups, buy an automotive freeze plug, ding it with a ball peen hammer, weld it to an eye bolt. Or buy them at Grainger.



Anyway, unless someone has dyno results that a cup works better, I call it snake oil. All you're trying to do is stop some of the reversion. The lollipop generally is open to about 45° being enough to slow reversion but not kill exhaust flow.

[jsachs1]

Make a lollipop from an eye bolt, a washer and a couple of nuts. Tack weld the washer into the eye bolt.

Adjust the angle of the lollipop to just break up reversion that causes exhaust fouling of the inlet fuel charge when the intake and exhaust valves are in overlap.



[attach=0,msg1395392]

Works like a champ. Install in about 2 inches 
John

[Ohio HD]

Make a lollipop from an eye bolt, a washer and a couple of nuts. Tack weld the washer into the eye bolt.

Adjust the angle of the lollipop to just break up reversion that causes exhaust fouling of the inlet fuel charge when the intake and exhaust valves are in overlap.



[attach=0,msg1395392]

Works like a champ. Install in about 2 inches 
John

Thanks John, good point about 2" in to the pipe.     

[hbkeith]

Always used this on my old Drag Pipe bikes , works great , i agree with snake oil on the cups

[Burnout]

Just to clarify.
A lolly pop is a band aide and does not "fix" drag pipes.
It just makes them more tolerable.
It does not fix the huge flat spot that most drag pipes cause.

[RTMike]

Reversion runs back up the inner walls of the exhaust pipes not the center,you are creating back pressure that will help with performance to a point as pointed out previously.

[Hossamania]

Everybody rips on drag pipes, but dang I loved mine. Nobody who rode near me did, but I loved them. And they looked cool, which ultimately made me look cool!
Flat spot? What flat spot? A down shift and off we go!

[Ohio HD]

https://youtu.be/KjKUKhHQLHg

[cheech]

Reversion runs back up the inner walls of the exhaust pipes not the center,you are creating back pressure that will help with performance to a point as pointed out previously.

Myth!
Air in, air out. The faster you do that and the more volume, power increases (along with corresponding fuel)
Back pressure is detrimental to that. No engine benefits from back pressure.
It's all about the reversion.

[cheech]

https://youtu.be/KjKUKhHQLHg

Edit in. Love the throwing them in the dumpster. Hurrah

[Ohio HD]

https://youtu.be/KjKUKhHQLHg

Edit in. Love the throwing them in the dumpster. Hurrah

Yeah, that was a nice touch.

[hbkeith]

Not everyone needs every bit of power at all times , most just want the dyno sheet, but  my Drag Bike with open pipes sure dont have any flat spots

[guido4198]

https://youtu.be/KjKUKhHQLHg

GREAT video....Thank you for posting that one.

[crock]

I'm running a 98" Shovel motor with 2" drag pipes. It was a little bit of a struggle but after taking 2 sets of the short baffles the you get from J&P or whoever and cutting them off at the transition from small to big making them into reversion cones and installing them at the inlet and about a foot from the outlet BINGO. There in no perceivable flat spot and it sounds great( to me). I know I can make more HP fine tuning with "good" pipes but I think drag pipes look and sound cool. And I haven't lost too many stoplight challenges either

[Deye76]

"short baffles the you get from J&P or whoever and cutting them off at the transition from small to big making them into reversion cones and installing them"
I did this years ago, (nothing more than a tube with some louvers, no packing, cut to about 2" in length) because the cops would stick a baton up the pipe, if it went in all the way you got a ticket, after installation the bike ran way better, still sounded good. The local cops did me a favor. 

[Hossamania]

Shovels and drag pipes go together like rum and coke. Made for each other.

[david lee]

are tapered turbos still around  i liked there sound

[Deye76]

Shovels and drag pipes go together like rum and coke. Made for each other.

Older Sportsters & drag pipes even better IMO. Hooked me at 14 years old.