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rharrison356
13th December 2006, 05:07
Well, in a moment of "Christmas Spirit" I purchased my bike a set of V&H mufflers. I still advocate baffle removal for those seeking to save $ and enjoy a much better sound than stock. (BTW, my de-baffled mufflers are on ebay, no-reserve). I did not notice any seat-of-the-pants power-difference between the V&H and de-baffled OEMs. The SE air cleaner did make a difference that can be felt. It would be interesting to note the flow-difference between de-baffled mufflers and aftermarket pipes. Anyone know of data to support my seat-of-the-pants impressions?

obiwan
13th December 2006, 08:34
Don't have any hard & fast data but the article I've linked below explains quite a bit.

In fact, it was one of the reasons I chose to go with the V&H slip-ons instead of removing the baffles from the stock mufflers.

Courtesy of another forum (can't remember which)
http://www.bigcitythunder.com/pages/understanding_exhaust.pdf

rharrison356
13th December 2006, 12:56
...
In fact, it was one of the reasons I chose to go with the V&H slip-ons instead of removing the baffles from the stock mufflers.The article was well written and I there is no reason to disagree with the writers. However, it does not answer the key question...what exactly is the difference. A dyno run would provide data across the powerband. I keep hearing the removing the baffles (from stock exhaust) lowers hp and torque...however, those who have done so do not report a "seat of the pants" change. Adding the V&H also did not result in a "seat of the pants" change, but putting the SE air cleaner on did. It would be fun to have a dyno day (any local dealer open to hosting one?)

Uncledaddy
13th December 2006, 13:09
I keep hearing the removing the baffles (from stock exhaust) lowers hp and torque...however, those who have done so do not report a "seat of the pants" change.

I pulled the baffles out of my stockers before I got the LSR's. With everything else stock, including jetting, my bike dynoed at 6ft/lbs less than the advertised spec. I could feel the difference in the lower rpms. I haven't dynoed since my full stage 1 but I know I got that power back and then some.

Gone
14th December 2006, 23:46
Well, in a moment of "Christmas Spirit" I purchased my bike a set of V&H mufflers. I still advocate baffle removal for those seeking to save $ and enjoy a much better sound than stock. (BTW, my de-baffled mufflers are on ebay, no-reserve). I did not notice any seat-of-the-pants power-difference between the V&H and de-baffled OEMs. The SE air cleaner did make a difference that can be felt. It would be interesting to note the flow-difference between de-baffled mufflers and aftermarket pipes. Anyone know of data to support my seat-of-the-pants impressions?

Joe Minton once did a flow-check on the stock mufflers and they only produced a crappy 49 cfm, relying heavily on the stout exhaust gas pressure to push it's way out. Minton and Jerry Branch did testing that showed knocking out the baffle discs would deliver about half the power gain of SE slip-ons - for near zero cost.

excel50
15th December 2006, 03:05
(BTW, my de-baffled mufflers are on ebay, no-reserve).
Can we get a link to that auction?

Mikel_NY
15th December 2006, 03:12
I have a posting that compairs the Cycle Shacks with and with out the baffles against the D&D 2 into 1 pipe.

the posting is in the DYNO CHARTS / 88" w/ D&D 2-1 pipe / post #8

rharrison356
15th December 2006, 03:31
(BTW, my de-baffled mufflers are on ebay, no-reserve).
Can we get a link to that auction?
Here it is: http://mail.mbts.edu/exchweb/bin/redir.asp?URL=http://cm.ebay.com/cm/ck/1065-29296-2357-0?uid=64342507%26site=0%26ver=LCA080805%26item=260 064884250%26lk=URL

rharrison356
15th December 2006, 03:33
I pulled the baffles out of my stockers before I got the LSR's. With everything else stock, including jetting, my bike dynoed at 6ft/lbs less than the advertised spec. I could feel the difference in the lower rpms. I haven't dynoed since my full stage 1 but I know I got that power back and then some.
Isn't the advertised spec "at the flywheel" and the dyno is "at the wheel?" If so, then 6 less is about right, factoring in a 12-15% loss at the wheel.

Don Burton
17th March 2007, 00:05
That's what I was thinking.

04ctd
17th March 2007, 01:29
the AC is more restrictive than the pipes is why your SOTP was goofy.