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Discussion Starter · #1 ·
I was considering some straight drag pipes for my Heritage. A friend told me that I would lose low end torque with straight pipes. Is that right. If so, is it a severe reduction, or something I wouldn't much notice? Also, is it harmful to the engine in any way?

Thanks in advance for any help.
 

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Knower of Stuff
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Well straight pipes provide very limited back pressure and over scavage at low RPM causing a drastic reduction in low end power. The more weight you put on the bike the more you will notice the change.
2 up you would definitly notice.
It will definity affect the tune of the bike and cause it to run lean down low. If not corrected could burn an exhaust valve.
 

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Humpin One Leg at a Time
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Subzero said:
I was considering some straight drag pipes for my Heritage. A friend told me that I would lose low end torque with straight pipes. Is that right. If so, is it a severe reduction, or something I wouldn't much notice? Also, is it harmful to the engine in any way?

Thanks in advance for any help.
Your loss of low end tourque is not severe, but is is noticible. Expect a loss of 6-12 ft pounds of tourque low end. It will still be there at the top end. There are a few things that you can do to keep the loss to a minimal if you are running true drag pipes. 1) get a set that step up in tube diameter.(bassani etc.) 2) throw a set of thundermonsters (or similar) in them. 3) or do both. Do a search on any of these and you will get tons of info. The pipes will not be harmfull if you get your biked tunned to them, or re-jetted if it is carbed. Keep one thing in mind. straight pipes are Loud As Fuk and IMHO nothing sounds better. It all just depends on what you like.
 

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just a note here i have seen AR 2" drags back as much tq & HP as a thunder header on some combinations
 

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I think it will sound great. Just put a set of Jesse James Hell Bent pipes on my friends Sportster and it runs great and sounds real good. Just re-jetted it and it gives the bike more power all around. Have a set on the way for my softail
 

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I Don't believe it. Never have seen drag pipes give anything better power all around. Drag pipes might give you more peak power, but you'll wind up with a hole in the mid range.
 

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Highly Seasoned Rider!
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Haagdakta said:
I Don't believe it. Never have seen drag pipes give anything better power all around. Drag pipes might give you more peak power, but you'll wind up with a hole in the mid range.

I would agree. I tried a set of Cycle Shack drag pipes on my Shovelhead a few years ago and it really ruined the low end torque. It ran very poorly across the board also and was way, way too noisy. Then I tried baffes and it ran even worse.

Since then I've used either a 2-1 with a SuperTrapp or a set of dual Paughco mufflers and I've got all of the torque down low again.

I sold the drag pipes on eBay. :)
 

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Hellbound Train
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Otto said:
just a note here i have seen AR 2" drags back as much tq & HP as a thunder header on some combinations
Since you have seen this, how about sharing with all of us.
 
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