HarleyTechTalk

>>What is a reverse megaphone effect?<<

HELLOOooo

That would be:

yuuUkkKKKK!

wouldn't it?

Quote from: ejk_dyna on November 09, 2009, 12:34:35 AM
<<EJ arent there 2-3 diffrent designs for a e-pipe. >>

yes this is the good one...also shows mountain core vs std core -



this version was available for both dyna and softail.  i don't think it is a coincidence that the rear header configuration wrapping around cam cover is also used by the road rage and r&b best performing lsr pipe.

Interesting to note the difference in length between the front and rear primary pipes. In some cases just the opposite from other pipes such as the Propipe where the rear is much shorter than the front.
It's also worth mentioning that it appears from testing the difference in primary length can be as much a 6" without affecting peak performance, however it does affect low rpm reversion.....some better than others.
JME,
Bob
PS question: Since it is universally agreed the E-pipe is/was a winner, why has no other pipe mfg simply copied the design (pretty easy to mfg) and marketed it as an E-replacement exhaust?
Wish there was an exhaust mfg on here to address why they haven't done it.

Note how close the Thunderheader primary pipe lengths are compared to the E-pipe:

that curved header only fit a few bikes.

My Heritage E is different, in fact I think I'll put it back on over the
bassanni pro streets

don't wanna be called a fag

rmmrmrmrmmmrmmrrmrmrmrmm!

The odd fire sequence of a 45* V-Twin presents some interesting challenges for tuning, even more so when the exhaust is 2:1 is combined with a common plenum, short runner intake manifold. In some cases the unequal length header pipes can aide in power production, sometimes they don't. Same holds true for equal length header pipes when used in 2:1 setups. Cam timing plays a big role here, as well as flow characteristics of the heads. Much tougher to make a one size fits all, off the shelf solution for these critters than other engine types.

Join the "Pipe of the Month Club" ... I hear they give out discount coupons. :>)

FWIW, I used "cut and try" a lot more when building exhaust systems for HD's than I usually do for other engine types.

Quote from: FLTRI on November 09, 2009, 11:09:13 AM

FWIW, we've found the Propipe to be more prone to low rpm reversion than other pipes with more equal-length primaries.

Bob would that be the bagger pro pipe or the pro pipe in general???

i have the wrap around cam cover style on my dyna ,the long one on bagger and have put the one for floorboard bike on a build i diid for a freind that works very well also ,the bike i was concerned with when i started this post is getting tuned now and was up to 37 disc on friday have not heard if anymore was put on since so i will have to wait and see how loud it is maybe i will need a amp for stereo .thanks pete

Quote from: ederdelyi on November 09, 2009, 07:00:37 AM
>>What is a reverse megaphone effect?<<

HELLOOooo

Ahh, so we have a long divergent cone connected to a short convergent cone 'cause ya know folks, we can't do this expansion all day and at some point we have to stop the madness...       

just saw brand new e-serias for softail with mountain core and heat shields on ebay, never been used , just thought i would let you know , i would try but with the rr cam plate dont think it would fit

Quote[/PS question: Since it is universally agreed the E-pipe is/was a winner, why has no other pipe mfg simply copied the design (pretty easy to mfg) and marketed it as an E-replacement exhaust?quote]


Bob its long been my thoughts that the mfg has found there is more money in the "look at my big tit chopper pipes" . I bothered my drag rep all the time since the White bros exhaust are now made by Burly brand and I could have swore he told me they are owned by Drag / Lemans corp I could be wrong though,  he's retired now but I'll try remember to give him a call .

tmwmoose ,vance and hines owns the rights t white brothers they are now making 4 wheeler pipes and v&h rep told me in laconia that were going to start making pipes for bikes ,we'll have to wait and see if that really happens or not ,thanks pete

Quote from: se on November 09, 2009, 01:10:56 PM
Bob would that be the bagger pro pipe or the pro pipe in general???

Bagger Propipe. The dyna/FXR isn't as bad. Kinda same as the Fatcat is different beteen the touring bike vs Dyna.

Quote[What is a reverse megaphone effect?/quote]



Sorry fuzznut I didn't mean to ignore you Ive just been running around today. I'm not the one qualified to explain this tuning scenario I just know its been around for a long time and was used a lot on dirt track bikes. if you saw a cutaway of the e-pipe muffler you see the long expanding megaphone and then the entrance to the muffler core tapers it down its like one long funnel with a super short one on its end and it all has to do with exhaust pulse tuning well there ya go I said I wasn't qualified but that didn't stop me from opening my big mouth now did it! what I should have said this  is better answered by the motor chef's here!!

Quote from: tmwmoose on November 09, 2009, 03:20:25 PM

Quote[What is a reverse megaphone effect?/quote]



Sorry fuzznut I didn't mean to ignore you Ive just been running around today. I'm not the one qualified to explain this tuning scenario I just know its been around for a long time and was used a lot on dirt track bikes. if you saw a cutaway of the e-pipe muffler you see the long expanding megaphone and then the entrance to the muffler core tapers it down its like one long funnel with a super short one on its end and it all has to do with exhaust pulse tuning well there ya go I said I wasn't qualified but that didn't stop me from opening my big mouth now did it! what I should have said this  is better answered by the motor chef's here!!

You mean a reverse cone like the Thunderheader?

R&B Racing LSR B Style  which they say is their best performing header



Bassani Road Rage same concept on rear header pipe.



...so e-pipe, road rage, lsr, t header all have similar rear head pipe configuration...seems to work pretty well.

Quote...so e-pipe, road rage, lsr, t header all have similar rear head pipe configuration...seems to work pretty well.

Yeah, this one works well too...

ejk_dyna   i have a mountain core that you can mount in any can. all mounting holes are threaded. i have a standard that core that mounts one o'clock and six o'clock looking in the outlet and a standard that mounts eleven o'clock and five o'clock. that must be the difference you're talking about between models. just curious

Steve at GMR used to run an E-Pipe on his 124" Deuce before he sold it. Maybe he can help you out.

Quote from: fuzznut5197 on November 09, 2009, 06:59:36 PM

Quote...so e-pipe, road rage, lsr, t header all have similar rear head pipe configuration...seems to work pretty well.

Yeah, this one works well too...

Fuzznut,

What pipe is that in your pic?

definitely WB head pipes