Drag pipe: would it hurt to go from 1 3/4 pipes to 2" pipe

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boddiley
Posts: 10
Joined: Fri Jul 13, 2007 2:50 pm

Drag pipe: would it hurt to go from 1 3/4 pipes to 2" pipe

#1

Post by boddiley » Tue May 17, 2005 9:55 pm

Was wondering how much if any would it hurt to go from 1 3/4 pipes to 2 in pipe?
Thanks....
Bo



Cotten
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Re: Drag pipe

#2

Post by Cotten » Tue May 17, 2005 11:48 pm

Only your wallet and performance will suffer, and perhaps your eardrums, but it will certainly boost your ego!

kell
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Re: Drag pipe

#3

Post by kell » Wed May 18, 2005 2:29 am

Amen.

PanPal
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58 FL
76 FLH All Original
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Re: Drag pipe

#4

Post by PanPal » Wed May 18, 2005 3:49 am

I've got a set that came with my second pan. The guy said the same thing. It didn't run any better with them, all they did was let the cops know which route he took back from the bar. I kinda like the 1 3/4 pipes. I can still rattle some windows riding through town and they sound great in the alleys. ;)

I might make some heat Shields for the 1 3/4" pipes out of the 2" set.

mbskeam
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Re: Drag pipe

#5

Post by mbskeam » Wed May 18, 2005 4:34 am

you loveum or hateum.
I just dont care for that weenie put, put sound
stay with the 1-3/4 pipes

mbskeam

Billy
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Joined: Tue Mar 23, 2004 6:57 am

Re: Drag pipe

#6

Post by Billy » Wed May 18, 2005 5:31 am

bodiddily-
2" should only be used on BIG HOT motors 90"+
Otherwise you just lose ex. port velocity.. & it'll run worse also..
1 3/4" is the ticket.
Drags have a severe 'torque dip' from 1800rpm's to 2700rpm's.(depending on motor) But they sound Cool!!
By their design, they are for WFO !!! & top end HP..
But, You can easily tune majority of the dip out, & still have the 'Thunder'.. Dyno's don't lie. They just give the facts.
1/4" bolts thru pipes, about 1" in from end of pipes.
Virtually eliminates the dip.. I drill them & hide the bolts. You would be surprised at the difference....& it's free
power, It's there, just not being optimized.
It is in my bikes..
I like to let the LEO's know I'm coming ;)

03Roadking
Posts: 195
Joined: Wed May 04, 2005 4:17 pm

Re: Drag pipe

#7

Post by 03Roadking » Wed May 18, 2005 11:19 pm

I'm still trying to figure out this 62 it has 1 3/4 drag pipes I think they call them 40' I'm not sure but the front pipe ends just under the trans. I put 4" long baffles in them because I live in the land of the bunny huggers CA. Is this OK??? what I would really like to find is some up sweeps that go close to the same angle as the frame but everything I see says you shouldn't use them because of ground clearance is this true
(56 hard frame with stock springer)

kell
Posts: 404
Joined: Sat Jun 19, 2004 2:58 am

Re: Drag pipe

#8

Post by kell » Wed May 18, 2005 11:58 pm

Well I think you better take up knitting instead of biking if you have to nuke everybody within five blocks just to keep alive.

By the way there's a trick you can do to make a tunable baffle for drag pipes. With a washer welded on a bolt through the pipe, or using a thumbscrew with the head inside the pipe, you can rotate it and vary the amount it impedes the flow of the gases.

mbskeam
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Re: Drag pipe

#9

Post by mbskeam » Thu May 19, 2005 12:19 am

hello,

Billy.....
if I put the bolt with the washer on it or just a bolt.will I have to rejet? is that what you found, or is the bolt just to help brake up the reversion pulses.
I made the washer on the bolt last year.
(called the baffle comp. and said to use these, and gave me the size for the washer on the ones they sell at 25.00,.... cool)
but have not used them as it run to good to mess with,that is I have the jeting down and a very smooth running engine in town at slow speeds and reaL good at highway speeds.
mbskeam

Billy
Posts: 781
Joined: Tue Mar 23, 2004 6:57 am

Re: Drag pipe

#10

Post by Billy » Thu May 19, 2005 1:07 am

Kell-
You said:
(Well I think you better take up knitting instead of biking if you have to nuke everybody within 5 blocks to keep alive)
What exactly are you talking about ???
I might try 'crocheting' ;)


Mbskeam-
In the 60's Honda's had "snuff-r-nots" washer on a stud.
You could just turn it to have open pipes.. Or not..
What I mentioned was just a 1/4" bolt thru pipe to break-up ex. pulses (no re-jetting required)

mbskeam
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Re: Drag pipe

#11

Post by mbskeam » Thu May 19, 2005 1:17 am

hello,
funny you talk about the snuff -r- nots, is that I have those on my 305 honda :-[, yes
I beat the hell out of that thing riding in the woods
I wonder why I still live today,

1 kid=3/4 brain
2 kids=1/2 brain
3 kids=NO BRAINS
cool about the bolt, more tinkering too do ;)
mbskeam

I think I'LL try macrowmay

Cotten
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Location: Central Illinois

Re: Drag pipe

#12

Post by Cotten » Thu May 19, 2005 2:10 am

Here's my favorite 'snuffer' for midrange-sucking open pipes, I worked this out when 2"ers first came appeared ('79?).

Get some 'perforated sheet metal', the kind thats nothing but 1/4" holes everywhere. Stainless is perfect.

Then roll it into a tube that will fit into the pipe and spring out to size. Slip it over a piece of water pipe for an anvil so you can take a chisel and cut between holes to make alternating triangle-patterns that can then be bent inward like common baffles. When you look down the center, it will be mostly daylight, and you can tweak them for more or less restriction. Cut them to the length you feel comfortable with, and then pop-rivet (or screw) them into the pipes, just out of sight, unless you have a dyno handy to find the 'sweetspot'.

These stop reversion back up the pipe, and give a much "throatier" exhaust note, and restore much of the midrange, as the exhaust pulse hits upon a cushion of the last pulse swirling instead of a hard metal blockage.

If you want them more 'open', just take a long screwdriver and 'adjust' them while in place!

fourthgear
Posts: 1390
Joined: Mon Apr 11, 2005 1:12 pm
Location: north florida

Re: Drag pipe

#13

Post by fourthgear » Thu May 19, 2005 1:02 pm

You can have 10 " pipes as long as I can ride on your left side .

Panama
Posts: 10
Joined: Thu Aug 30, 2007 9:13 pm
Location: Apple Valley, CA

Re: Drag pipe

#14

Post by Panama » Tue May 24, 2005 4:56 am

Yeah the louder the better. I really like setting off all the car alarms with the pipes singing at the top of there lungs. Neighbors love me.

Loud Pipes Save Lives

58flh
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Bikes: 1958flh 1969sporty,had a knuckle but sold back to original owner
Location: NEW JERSEY

Re: Drag pipe: would it hurt to go from 1 3/4 pipes to 2" pi

#15

Post by 58flh » Sun Aug 07, 2011 1:40 pm

Well everybody pretty much summed it up for ya! :twisted: Unless you are running big-inch motors on the 1/4, stick with the 1-3/4. Anyway if you do go 2-inch your lowend tourque will suffer---i.e. leaving a redlight. This type of tube & larger are for top-end breathing/& it wont help you any unless you have correct-bumpstick,oversize valves high comp. ratio E.T.C. --& plan to stay at 6000 & up in the R.P.M.! The 1-3/4 are the better choice for a daily driven bike. I run them ,with a reworked Bendix, & NO PROBLEMS HERE! The socalled neighbors hate us /for setting car alarms off all the time/ & from all this 1 70+ yr old woman had the balls & stood-up to my face, I dont do any dumb-shit like rev-ups---I roll-off at idle, Then my OLady had a cup of jo & explined to her/ all the Jerkoffs that dont look or see /but they hear! /Now WE are great friends! /THEY just need to be told why. Also back to the topic, 2 inch is fine if you make the baffle as per (COTTONS) sugestion! Just remember NEED BACKPRESSURE not much but some, it will make the bike run better-you wont be foulin plugs because of higher JET sizs, the idle will be good-no need to rev the piss out of it every time you catch a light-so the plugs wont/ load-up! & when your on that longstretch where you can hold her at 105 MPH for awhile she will exhale beautifully!(Good-Luck on your decision{you will make the right choice that is for your needs} Alot of the men on this sight (KNOW THIER BIZ.) Keep it up-right & in 4th & twist that wick! 58flh-----yea yea I know BLABLA just could not control my rambling. apologies :lol:

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