why does 2 into 1 exhaust giver better performance?
Ultimate HDF Member
Joined: May 2008
Posts: 6,642
Likes: 48
From: Ogden, UT
You're looking at peak numbers only. Some 2-1 pipes are making 10 more hp in the mid range than a drag pipe and 5 more than other 2-2. If there was a chart for torque, you would see bigger differences. And you can and will feel 5 hp on a bike. It is equivalent to a 20-30 hp gain on a car. Most stage 1 upgrades are around 10 hp and it is night and day. You will definitely feel 5. A good 2-1 vs. a good 2-2 isn't just a difference of a rider. Same riding skills and the 2-1 will win.
Bottom line, if you took 2 identical bikes except for the pipes, one would not consistently out perform the other, there are too many variables in riding for starters.
If you have ever raced it is not unusual for the very same car to never hit exactly the same time in a 1/4 mile, even on the same day with the same driver. Shift points are not always hit exactly the same etc...
It's all about matching components, tuning, and most importantly the rider/driver skills. I have seen more than 1 driver turn a 10 second car into an 11 second car and visa-verse.
The whole point as far as I am concerned for a street cruiser, pick the pipes you think look and sound best for you, if you are building a serious racer the theory behind pipe design will probably mean more to you.
Ultimate HDF Member
Joined: Apr 2010
Posts: 7,138
Likes: 26
From: Southern Oregon
You're looking at peak numbers only. Some 2-1 pipes are making 10 more hp in the mid range than a drag pipe and 5 more than other 2-2. If there was a chart for torque, you would see bigger differences. And you can and will feel 5 hp on a bike. It is equivalent to a 20-30 hp gain on a car. Most stage 1 upgrades are around 10 hp and it is night and day. You will definitely feel 5. A good 2-1 vs. a good 2-2 isn't just a difference of a rider. Same riding skills and the 2-1 will win.
Thread Starter
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Road Captain
Joined: May 2011
Posts: 594
Likes: 1
From: minnesota
Well i am generally a form follows function kind of guy, I am doing very little to my bike just for the sake of looks, namely the bar change, and swapping out the badges for some pan style badges that i like more.
Other then that it is performance and useability mods. That is why I asked about this, I am not really big on the 2 into one look. It is not a deal breaker for me, but i just dont dig it like i do the 2 into 2. On the other hand performance is more impoortant to me, so on my stage II bike, i dont want to give up 6%-10% of useable HP or TQ.
For me the best looking pipes are the V&H big shots black. But if i am going to take an 85hp / 100 tq motor down to a 76hp 90tq motor by using them, i wont do it.
Other then that it is performance and useability mods. That is why I asked about this, I am not really big on the 2 into one look. It is not a deal breaker for me, but i just dont dig it like i do the 2 into 2. On the other hand performance is more impoortant to me, so on my stage II bike, i dont want to give up 6%-10% of useable HP or TQ.
For me the best looking pipes are the V&H big shots black. But if i am going to take an 85hp / 100 tq motor down to a 76hp 90tq motor by using them, i wont do it.
Outstanding HDF Member
Joined: Dec 2010
Posts: 2,036
Likes: 8
From: Temecula, CA
You can justify anything you want in one way or another.
Bottom line, if you took 2 identical bikes except for the pipes, one would not consistently out perform the other, there are too many variables in riding for starters.
If you have ever raced it is not unusual for the very same car to never hit exactly the same time in a 1/4 mile, even on the same day with the same driver. Shift points are not always hit exactly the same etc...
The whole point as far as I am concerned for a street cruiser, pick the pipes you think look and sound best for you, if you are building a serious racer the theory behind pipe design will probably mean more to you.
Bottom line, if you took 2 identical bikes except for the pipes, one would not consistently out perform the other, there are too many variables in riding for starters.
If you have ever raced it is not unusual for the very same car to never hit exactly the same time in a 1/4 mile, even on the same day with the same driver. Shift points are not always hit exactly the same etc...
The whole point as far as I am concerned for a street cruiser, pick the pipes you think look and sound best for you, if you are building a serious racer the theory behind pipe design will probably mean more to you.
It's all about matching components, tuning, and most importantly the rider/driver skills. I have seen more than 1 driver turn a 10 second car into an 11 second car and visa-verse.
Yes, there are a lot of variables that go into a quarter mile time but that doesn't mean that one pipe isn't going to give the bike more potential than another. You race so you know that quarter mile improvements are often measured in 1/10ths of a second thus even small improvements are still improvements.
Road Master
Joined: Jul 2011
Posts: 1,016
Likes: 3
From: West New york, NJ
Well i am generally a form follows function kind of guy, I am doing very little to my bike just for the sake of looks, namely the bar change, and swapping out the badges for some pan style badges that i like more.
Other then that it is performance and useability mods. That is why I asked about this, I am not really big on the 2 into one look. It is not a deal breaker for me, but i just dont dig it like i do the 2 into 2. On the other hand performance is more impoortant to me, so on my stage II bike, i dont want to give up 6%-10% of useable HP or TQ.
For me the best looking pipes are the V&H big shots black. But if i am going to take an 85hp / 100 tq motor down to a 76hp 90tq motor by using them, i wont do it.
Other then that it is performance and useability mods. That is why I asked about this, I am not really big on the 2 into one look. It is not a deal breaker for me, but i just dont dig it like i do the 2 into 2. On the other hand performance is more impoortant to me, so on my stage II bike, i dont want to give up 6%-10% of useable HP or TQ.
For me the best looking pipes are the V&H big shots black. But if i am going to take an 85hp / 100 tq motor down to a 76hp 90tq motor by using them, i wont do it.
Ultimate HDF Member
Joined: May 2008
Posts: 6,642
Likes: 48
From: Ogden, UT
All true...
...except the second half of this. While it is true I've seen a driver make a 10 second car into an 11 second car I've never seen it the other way around. A driver cannot make a car or bike go down the quarter mile any faster than the car or bike is capable of going. Now, maybe the car never had a driver that could "put it all together" under the ideal conditions and get the best time the car was capable of, but in the end the VEHICLE is only capable of so much.
Yes, there are a lot of variables that go into a quarter mile time but that doesn't mean that one pipe isn't going to give the bike more potential than another. You race so you know that quarter mile improvements are often measured in 1/10ths of a second thus even small improvements are still improvements.
...except the second half of this. While it is true I've seen a driver make a 10 second car into an 11 second car I've never seen it the other way around. A driver cannot make a car or bike go down the quarter mile any faster than the car or bike is capable of going. Now, maybe the car never had a driver that could "put it all together" under the ideal conditions and get the best time the car was capable of, but in the end the VEHICLE is only capable of so much.
Yes, there are a lot of variables that go into a quarter mile time but that doesn't mean that one pipe isn't going to give the bike more potential than another. You race so you know that quarter mile improvements are often measured in 1/10ths of a second thus even small improvements are still improvements.
I have won races with margins as small as 20 thousandths, so yes in racing every little bit counts. On a street cruiser, not so much.
Outstanding HDF Member
Joined: Dec 2010
Posts: 2,036
Likes: 8
From: Temecula, CA
Absolutely agree...that's why I have Big Shots on my Dyna. I don't need that little extra that a 2 into 1 would provide and was going for "better than stock" performance with look and sound I liked.
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Road Warrior
Joined: Aug 2011
Posts: 1,335
Likes: 3
From: Ca.
hehe
Road Master
Joined: Jul 2011
Posts: 1,016
Likes: 3
From: West New york, NJ
And with that I believe this thread has its answer.