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XL EXHAUST TESTS
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Introduction
In the winter of 12-13, we tested a few systems for XL's on our shop mule 2007 883/1250 and showed the results on the XL Forum.
Interest grew and soon we had people sending us their pipes for testing. As a result, we've compiled a stack of dyno results
for some of the more popular exhaust systems, revealing a lot about how they perform, and that information is presented here.
We'll continue to add to this page as we test more pipes so be sure to check back.
Over time, the bike has undergone changes that affect it's output, and furthermore,
changing weather conditions also affect results, as dyno correction processes aren't perfect. Once we realized this was going to be
an ongoing process of testing pipes and the bike was simultaneously undergoing changes, we've started taking care when testing
a pipe to always do a same-day test of a "reference" pipe. The pipe we chose to use as the reference is the Patriot Defender. It's a
great choice because it's one of the best performing pipes on the market (as of this writing it's THE best), and it although it's
made for a rubber mount (2004-newer), it can also be fairly easily hung on a solid mount (86-03). Anyway, be aware that some of the
early tests were not same-day comparisons; however, for those comparisons, there were no differences in the configuration of the bike.
So anyway, if you want to know how one pipe did against another, look at how each pipe did against the Patriot. That'll give a much better idea of how the pipe actually performs
than a direct comparison.
The following results are presented in reverse order of how they were tested, i.e. the most recent test is first.
If you have a pipe you'd like to see tested, please contact us. All we require is that it can be hung onto a 2007 Sportster, and it also needs to have oxygen
sensor bungs. We'll have you ship it to us, we'll test it, develop a Powervision map that you're welcome to have, and return it to you.
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Gallop Badlands
Gallop Badlands 2:1 for Sportster
Comparison to the Reference Pipe
Test date: 1/30/22
Test bike: 2007 XL883 Sportster, equipped with a basic 883-1275 conversion (stock 883 heads & stock cams)
Comments:
This pipe has been generating a lot of buzz lately, and several customers asked about it's performance. So we acquired and tested one.
The pipe is reasonable on the bottom end to mid range, but just flat-lines on top. Not unlike the Cone Engineering in that regard.
With the Cone, we were able to test some experimental, much larger mufflers (provided by Cone) that removed this flat lining on top and made the pipe
a reasonable performer. The implication was that the standard muffler was just too restrictive to work well on top, it caused too many pumping losses.
It's possible the same is happening with the Gallop. The power curve sure looks the same, like we've reached the limit of how much air it can flow.
The TIG welded stainless construction gives the pipe an industrial, all-business look. They offer it in a few different finishes.
Similar to the Cone, the Gallop Badlander's muffler and collector are welded together into a single unit, and held to the head pipes by springs.
Very tight clearance for a long wide band sensor on the rear.
Similarly tight clearance for a long wide band sensor on the front.
Bottom line, although it's a good looking pipe, we can't in good conscience recommend it as a performance pipe. This is just a basic
conversion, a relatively low powered build in the world of Sportsters, and it's pretty badly constraining it. We would expect the
pipe to limit high power builds by even more. Gallop, if you're listening and you have an improved design system, let us know and we'll retest.
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SE Street Performance Slip-Ons
Screamin Eagle Street Performance Slip-Ons
Comparison to the Reference Pipe
Test date: 1/26/2019
Test bike: 2007 XL883 Sportster, equipped with stock EFI 1200 heads, flat top 1275 kit, Jackhammer 570 Cams, Air Hammer air cleaner, and tuned with a Dynojet Powervision.
Comments:
These slip-ons are offered by HD in the Screamin Eagle catalog. Here's an excerpt from the 2019 SE catalog describing them:
We tested the chrome version, part number 80503-07. The slip-ons are stamped with the part numbers 80599-07 (front) and 80503-07 (rear), but the set sells under part number 80503-07.
They are 50-state EPA compliant and are only marginally louder than the stock mufflers.
As far as the power goes, it's strong down low, but dies early and levels out above 5000rpm. Very similar to the Cone 2:1 tested below in that regard. We believe this is due to a high
level of restriction that just prevents pumping more air through the pipe beyond a certain point.
If you're seeking bottom end to mid range power, and not concerned about the power above about 4400rpm, and you want a quiet exhaust, these are the slip-ons for you. If on the other
hand you want top end power, avoid these.
SE 80503-07 Street Performance Slip-Ons Being Tested on the Dyno
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Cone Engineering
Cone Engineering 2:1 for Sportster
Comparison to the Reference Pipe
Test date: 2/10/2018
Test bike: 2007 XL883 Sportster, equipped with an undisclosed experimental engine combination. It's 1250cc and the cams however have enough overlap to make differences in exhaust
system very apparent.
Comments:
This is a great looking pipe. Everyone raves about it's looks and this generated a lot of interest in seeing us test it.
The cone muffler and collector are welded together into a single unit, and held to the head pipes by springs. The collector attaches to a bracket that comes off the motor that looks plenty
strong enough to support it. The whole thing was very easy to install, just bolt up the head pipes loosely, mount the collector and attach the springs, and then tighten up the head pipes at the heads.
Clearance for the long wideband sensors was fine as well.
As far as the power goes, it's a bit weak down low, pulls hard through the middle, and then flattens out on top. The flattening on top is interesting. This is something we've seen in other pipes and we believe it has to do with
pumping losses. You hit a point where you just can't push more through the pipe.
We were provided with a couple of experimental reverse cone megaphone style mufflers to test, both of which were bigger than the supplied piece, and both made a marked improvement in the dyno results. The bigger one even beat the Patriot
through the meat of the rpm range, although it fell about 3hp short on top. It would be nice if Cone offered this bigger muffler as a performance enhancement alternative.
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Arlen Ness F-Bomb
Arlen Ness F-Bomb Sportster
Comparison to the Reference Pipe
Test date: 2/4/2018
Test bike: 2007 XL883 Sportster, equipped with an undisclosed experimental engine combination. It's 1250cc and the cams however have enough overlap to make differences in exhaust
system very apparent.
Comments:
The shape of the torque curve tells the story. It pulls, then it pushes back, then it pulls again, then it pushes back again.
It's main pull centered around 4700rpm is high enough in the rpm range to make for a very good top end number. Power is just torque times rpm, so making torque on the right hand side of the chart
is how you make big power. In fact, this is the first pipe we've ever tested to effectively tie the Patriot on the top end. The half-a-horsepower difference is well within the ability of a dyno to accurately
differentiate. This should really be considered a tie.
However, through the meat of the riding range, the reference pipe beats it pretty handily. It has better diffusion, pulling over a wider rpm range, instead of the push-pull-push thing the F-Bomb has going on.
Overall, we liked the pipe. Any time a pipe puts up a big number, it's hard to complain too much. Even for me. It'd be nice if it diffused better and provided a wider powerband. But hey, with the Patriot discontinued
(we're anxiously awaiting the new version), if you need a pipe that puts up a big power number, here's your huckleberry.
Other comments: good hefty support bracket. Well packed. Comes with reducer bushings for the small oxygen sensors found on 2014+ XL's. Also comes with plugs if you're putting it on a bike without sensors (i.e. 04-06 XL's).
No issues with long wideband sensors, except the front comes out in between the two frame down tubes. Very difficult to get to the lower flange nut on the front head pipe, impossible even with a 1/4 drive swivel socket.
You'll be using a wrench and accessing it from the port side of the bike (that's left for you landlocked folks).
It comes with heat shields, we just don't install them for the purpose of performance testing. As you can see, the head pipes have a single step, and they're coated with something. Possibly a heat retaining coating.
The muffler chrome did not discolor during the course of the testing.
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Two Brothers Comp-S 2014+
Two Brothers Comp-S exhaust for 2014+ Sportster
Comparison to the Reference Pipe
Test date: 6/25/2017
Test bike: 2007 XL883 Sportster, equipped with an undisclosed experimental engine combination. I don't want to talk too much about it. I'll just say it's a relatively mild 1250.
We work on more than just pushing the limits of power, we also work on improving and refining low cost combinations as well. The cams however have enough overlap to make differences in exhaust
system very apparent.
Comments:
This is the 2014+ version of the Two Brothers Comp-S tested below. Although the primary change with this pipe is to make it fit the 2014+ models, they also made some design changes that affect the performance
and ground clearance.
The shape of the torque curve tells the story. It pulls, then it pushes back, then it pulls again, then it pushes back again.
This push-pull thing with pipes is not unusual. There's a technical explanation behind why a pipe wants to behave this way. It has to do with pressure waves traveling up and down the pipe, both positive and
negative, and the type of wave that arrives at the chamber during the overlap window, i.e. when both valves are open. During overlap, the exhaust is connected to the intake, and this happens just as the intake
stroke is starting (even slightly before), and therefore the exhaust has a big effect on intake flow and thus cylinder fill. If the exhaust comes in with a pull right then, you get a head start on the upcoming
intake cycle, more cylinder fill, and therefore more torque. If the exhaust pushes back right then, you get less cylinder fill and therefore less torque. Power is just torque times rpm, so it reflects what the
torque curve is doing.
The reason it pulls at some rpm's and pushes back at others is because these pressure waves travel up and down the pipe, reflecting off each end, at a constant speed regardless of the rpm of the motor. The
interval between overlap windows of course varies depending on the rpm of the motor. So as you change the rpm, the type of pressure wave that ends up hitting the chamber during overlap changes, and the cylinder
fill changes.
A well designed exhaust will diffuse and broaden a negative pressure wave (i.e., a "pull") such that it arrives during overlap over a much wider rpm range. This results in a flat or broad parabolic shaped torque
curve, indicating good cylinder fill over a wide range.
A less well designed pipe will pull, push back, pull, push back as the rpm climbs.
Unfortunately, when it comes to pipe design for HD's, looks and sound trump performance almost every time. I really don't think very many HD pipe designers at all put much engineering into the performance aspect
of their pipes. Which is unfortunate, because the pipe is a major, major piece of the performance formula. It has a profound effect on the motor's performance.
OK, enough ranting.
The pipe is really nice looking. It looks like it would provide good ground clearance. They definitely tucked it in closer to the motor as compared to the other version. So they made at least one good improvement.
Before it's seen heat. It has heat shields, but I don't bother with them for performance testing. Sorry about the lemonade can, I didn't even realize it was there until I pulled the pics out of the camera.
After it sees some heat, it turns gold. Normal stuff for stainless.
This pic shows how they tucked it in compared to the old one. I had not yet installed the springs as you can see. But this is where it sits.
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Bassani Road Rage 3
Bassani Road Rage 3 two into one for Sportster
Comparison to the Reference Pipe
Test date: 4/19/2017
Test bike: 2007 XL883 Sportster, equipped with an undisclosed experimental engine combination. I don't want to talk too much about it. I'll just say it's a relatively mild 1250.
We work on more than just pushing the limits of power, we also work on improving and refining low cost combinations as well. The cams however have enough overlap to make differences in exhaust
system very apparent.
Comments:
The shape of the torque curve really tells the story. It has a bad reversion down low, then a real hard pull that peaks around 3900rpm, and then it dies on top. In other words, poor diffusion.
Pipes that push back and pull at different rpm's like this are acting almost like an open pipe. A poorly diffused pipe will alternate between a strong negative wave and a strong positive wave arriving at the chamber
during overlap, depending on the rpm of the engine. This is because the pressure waves travel in the pipe at a relatively constant speed regardless of rpm, but changing the rpm changes the interval between
overlap windows. So you get a negative pressure wave for awhile, then a positive wave, then a negative wave, etc. Conversely, a well diffused pipe will generate a broad negative wave that pulls evenly over the
entire rpm range, creating a flat or parabolic shaped torque curve.
Unfortunately, this is not an uncommon condition with pipes. You can find many pipes on this page that perform this way.
As you can see, it edges out the Patriot from about 3000 to 4200rpm. But above that, the Patriot clobbers it.
Special thanks to valued HAMMER customer Dan Cunningham for sponsoring this test. This is at least the third test he's sponsored now.
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Vance & Hines Competition Series 2:1
Vance & Hines Competition Series 2 into 1 - Standard baffle, not the quiet baffle
Test bike: 2014 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original XL883 Heads
HAMMER PERFORMANCE 1250 Kit with 30 Degree Reverse Dome SLEDGE HAMMER Pistons
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Comments:
Big thanks to HAMMER customer Charles Osgood for this data. He had purchased and installed our
100+ horsepower conversion kit, failed to achieve the advertised number, and then on our advice he switched over to the Patriot Defender.
As you can see, he literally got 12 more horsepower by changing the pipe, and didn't lose anything anywhere in the rpm range.
The moral of the story is that the pipe is an absolutely critical part of a performance build and it can make or break your result.
Probably 99% of the people who contact us looking for a performance package already have an exhaust, and an air cleaner for that matter. We try to warn people up front that the
result is only going to be as good as the part that holds the motor back, and if their exhaust or air cleaner is not up to the job, they can't expect to make the advertised number. There's nothing
more frustrating than selling a customer a performance package and watching him come up short because his exhaust choice holds him back. Unfortunately, good data on exhaust performance
is not forthcoming from the manufacturers. Of course, correcting that situation is the whole point of this tech article. It's amazing to see how many high dollar pipes perform poorly.
This is yet another example.
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Cobra PowerPro HP
Cobra PowerPro HP 2 into 1
Horsepower Comparison of the Reference Pipe to CobraPowerPro HP
Torque Comparison of the Reference Pipe to CobraPowerPro HP
Test date: 2/8/2016
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE "SLEDGE" Head Porting Service on a set of XL883 Heads
HAMMER PERFORMANCE 1250 Kit with
30 Degree SLEDGE HAMMER Pistons
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Cranking Compression is 205psi and it's running on pump gas.
Comments:
Packed in a lot of plastic wrap, bubble wrap, and newspaper. One of these pipes that takes a half hour to extract from the box and packing, like the D&D. Annoying. Pipe makers should look at how Two Brothers does it.
Next annoying thing was the installation. The rear head pipe comes into the collector at an angle. That makes it hard to install.
The instructions say to install the front head pipe to the motor, and the rear head pipe to the muffler, then put the muffler/rear head pipe assembly into the front head pipe and rear cylinder.
Well, that doesn't work so good, because when you put the rear head pipe into the collector, you don't know what rotational position it needs to be in. After 20 minutes or so of struggling and saying lots of bad words,
we got it on there.
O2 sensor placement isn't terrible, but the front comes closer to the lateral link mount than I'd like, when used with long wideband sensors anyway.
The mapping dialed in without any real drama. But as you can see by the chart, the pipe isn't behaving very well before 4200rpm. Above 4200 it's a reasonably flat torque curve, but it's definitely pushing back below that.
With respect to the pipe's comparison to the reference pipe, well, the left side of the chart isn't the Patriot's strong point either, but it's at least cleaner down there.
The Cobra managed to eke out a small advantage from 4200 to 5000, but then it's Patriot all the way, ending up roughly 5hp better on the top.
The verdict? We wouldn't call it a terrible pipe, but it didn't really impress us either.
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Rush Slip-Ons
Rush 3 Inch Slip-Ons with 1-3/4 Inch Baffles
Comparison of the Reference Pipe to Rush Slip-Ons
Test date: 2/7/2016
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE "SLEDGE" Head Porting Service on a set of XL883 Heads
HAMMER PERFORMANCE 1250 Kit with
30 Degree SLEDGE HAMMER Pistons
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Cranking Compression is 205psi and it's running on pump gas.
Comments:
Rush makes a number of different slip-ons. These are the 3 inch slash-down versions with the 1-3/4 inch baffles.
Very easy to install and mapped right in, no issues.
Impressive result for a pair of slip-ons! Nice broad torque curve with no real push-backs anywhere. Equal or better to the Patriot up to 5600rpm, at which point the Patriot takes over.
These outperform a lot of 2 into 1's, which is amazing for a set of slip-ons.
Bonus Dyno Comparison
We were also curious about how these compared to the Cycle Shack slip-ons, and since we still had our Cycle Shacks sitting around, we threw them on and mapped them in and did a direct comparison:
The graph tells the story. Below about 4200rpm they're equal. Above that, the Rush slip-ons take over, and end up 3.5hp on top.
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Supertrapp 2 into 2
Supertrapp 2 Into 2 with 20 Discs and Closed End Caps
Supertrapp 2 Into 2 with 20 Discs and Competition End Caps
Comparison of the Reference Pipe to Both Configurations of the Supertrapp 2 into 2
Test date: 2/6/2016
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE "SLEDGE" Head Porting Service on a set of XL883 Heads
HAMMER PERFORMANCE 1250 Kit with
30 Degree SLEDGE HAMMER Pistons
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Cranking Compression is 205psi and it's running on pump gas.
Comments:
With the closed end caps, this pipe has a pretty flat and wide torque curve. Switch over to the competition caps and you gain some power through the middle and on top and
pay for it with a medium-small reversion centered around 3200rpm. It's really not unlike the Short Shots, tested with and without baffles.
The comparison to the Patriot is interesting. Comparing the Competition Cap equipped Supertrapp (red) to the Patriot
(blue), you immediately notice the reversion which causes the Patriot to win from 2700 to 4200rpm. Then the Supertrapp has a hard pull and beats
the Patriot from 4300 to 5400rpm. From 5500rpm on up, the Patriot asserts itself and takes over, ending up 3hp better on the top number.
Now compare the closed cap Supertrapp (green) to the Patriot (blue). They're basically dead even to 4800rpm, then the Patriot clobbers it the
rest of the way up, beating the Supertrapp by 5.7hp on the top.
Closed End Caps (left) and Competition End Caps (right)
The Test Bike on the Dyno
Mounting wasn't too bad. It's kind of a funky rear mount, and it requires the sprocket cover to be in place, so I had to go find ours -
it's something I took off a long time ago to simplify pipe swaps and I've never put it back on.
Sensor placement was not good. I think it would probably be ok for the stock narrow band sensors, but for the widebands, the rear was
practically hitting the starter, and the front would not clear the bracket for the stabilizer link. I had to take the bracket off. So be
aware of that if you're thinking of widebands.
Like all Supertrapps, the pipe was relatively quiet. It lacks the sharp tone that you get from so many pipes.
One quality note here. The pipe as we received it for testing was in used condition. We discovered this crack in the rear head pipe that went halfway around the pipe
and the oxygen sensor bung. We had to stitch it up with the welder before we could test.
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Two Brothers Comp-S
Two Brothers Comp-S
Comparison of reference pipe to Two Brothers Comp-S
Test date: 1/17/15
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE "SLEDGE" Head Porting Service on a set of
EFI XL1200 Heads
HAMMER PERFORMANCE 1250 Kit with
30 Degree SLEDGE HAMMER Pistons
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Cranking Compression is 205psi and it's running on pump gas.
Comments:
The pipe has a reversion down low, pulls hard centered around 5000rpm, and then slowly loses cylinder fill from there. The shape of the torque curve tells the story. Since power is just torque times rpm, the power curve reflects what the torque curve is doing.
It beats the Patriot from about 3900 to 5600rpm, but above and below that, the Patriot is stronger, with more the 4hp extra on top.
The pipe was very easy to install. Each head pipe is a separate piece, which slip into the muffler/collector assembly and held together with a pair of springs. The springs are on the back side, out of view.
A fairly hefty bracket attaches the muffler to the motor. Oxygen sensor bungs are well located and there were no clearance issues with the longer wideband sensors used for tuning.
There's one thing about the mounting, however. The pipe sticks out the right side, away from the motor, more than other pipes. We have concerns about this compromising cornering clearance. The low point on the pipe is
where the front head pipe comes into the collector.
The pipe is a brushed stainless finish and is beautiful. The stainless turns gold with heat. Nice looking heat shields are provided.
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RSD Tracker
RSD Tracker Dyno Result
Comparison of reference pipe to RSD Tracker
Test date: 4/4/2014
Test bike: 2007 XL883 Sportster equipped as follows:
Modified EFI XL1200 heads
HAMMER PERFORMANCE 1250 Kit with Flat Top Pistons
HAMMER PERFORMANCE "JACKHAMMER 570" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10:1 and it's running on pump gas.
Comments:
This is the RSD high pipe, two into one. It performed very similarly to
the RSD Slant two into one low pipe tested below.
The shape of the torque curve tells the story. The pipe has a bit of a reversion down low, pulls really hard centered around 4000rpm and then dies after that, with some signs of leveling off on top.
Since power is just torque times rpm, the power curve reflects what the torque curve is doing.
Bonus Data on this Pipe
On 8/9/14, a customer brought us a bike for a tune-up that was fitted with one of these pipes:
This was a 2001 XL883, fitted with SE CNC ported heads, an SE 1200 kit, SE cams, a CV44 carburetor, and a Ness Big Sucker air cleaner. Although the RSD tracker is only made to fit
2004 and newer Sportsters, the owner had fabricated a bracket and got it to fit.
As you can see we got about the same shaped torque curve, confirming the previous result on our in-house test bike.
The owner was present and when he saw this result, he gave us license to modify the baffle as needed to make it run better. We started by drilling three 3/8" holes
in the baffle plug, which was quick and easy to do without even removing the baffle. It made very, very little difference however.
So then we decided to completely remove the baffle, which netted this result:
This is just astonishing. It completely inverted the result as you can see; at rpm's where the baffled pipe pushed back, it now pulled, and at rpm's where the baffled pipe pulled, it now
pushed back.
Perhaps most astonishing is how the bike picked up an amazing 21 horsepower on the top! This is an indicator of a very restrictive baffle causing massive pumping losses.
However, without the baffle the bike has a bad reversion-induced hole right in the middle of the rpm range, which the owner of the bike wasn't happy with. So our next experiment was to simply cut the
baffle in half, completely removing the tail end and the baffle plug. Here's what happened:
Now we're getting somewhere! Although we didn't really cure the low rpm reversion, we largely recovered the middle and top end by radically reducing the pumping losses. The owner was happy
with this and we sent him on his way.
And finally, here are some additional sheets to compare all three configurations we tested:
That's a pretty dramatic difference considering the only changes between the pulls were changes to the baffle. It's obviously a very restrictive baffle that's just killing the performance.
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Bassani Slip-Ons
Bassani Slip-Ons Dyno Result
Comparison of reference pipe to Bassani Slip-ons
Bonus Comparison - Bassani Slip Ons vs. Cycle Shack Slash Cut Slip-Ons
Test date: 3/30/2014
Test bike: 2007 XL883 Sportster equipped as follows:
Stock EFI XL1200 heads
Stock 1200 Cylinders and Flat Top Pistons
Mild street performance cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 9.7:1 and it's running on pump gas.
Comments:
We tested these largely because the Bassani's dominated a comparison test of slip-ons found on another web site. However, that test did not include the ever-popular Cycle Shack slip-ons, which cost roughly half what the Bassani's cost.
The Bassani's induced a pretty noticeable reversion at low rpm, followed by a strong pull in the middle, and then slowly died as the rpm went up.
Performance is similar to the Cycle Shacks, but not quite as good. Less diffusion, as the Bassani's are concentrating their wave more in the middle to the detriment of bottom and top end.
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Cycle Shack Slash-Cut Slip-Ons
Cycle Shack Slash Cut Slip-Ons with Standard Baffles Result
Cycle Shack Slash Cut Slip-Ons Without Baffles Result
Comparison of reference pipe to CS Slash Cut Slip-ons with & without Baffles
Test date: 3/8/2014
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "CRUSH" Head Porting Service on a set of EFI 1200 heads
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
HAMMER PERFORMANCE Ported Throttle Body and Intake Manifold
Tuned with Dynojet Powervision
Compression ratio is 10.9:1 and it's running on pump gas.
Comments:
With the baffles installed, the CS slip-ons pull real well everywhere except up high, where the Patriot pretty much stomps it, pulling nearly 10hp more.
With the baffles removed, the CS slip-ons have a bad reversion down low but then give a real strong top end pull. They miss the Patriot's top number, but only by a whisker.
The above pulls were all 4th gear. We did some 5th gear pulls and got 105.8hp with the baffles in place. We did not do any 5th gear pulls with the Patriot or with the unbaffled Cycle Shacks.
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Stock 2007 Exhaust System
Stock exhaust result
Comparison of Reference Pipe to Stock 2007 Exhaust System
Test date: 3/8/2014
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "CRUSH" Head Porting Service on a set of EFI 1200 heads
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE "SLEDGE" Air Hammer Air Cleaner
HAMMER PERFORMANCE Ported Throttle Body and Intake Manifold
Tuned with Dynojet Powervision
Compression ratio is 10.9:1 and it's running on pump gas.
Comments:
As a prelude to the test of the Cycle Shack slip-ons above, we decided to test the stock mufflers first. 24 horsepower is a LOT to give up to the Patriot!
We had a lot of trouble dialing in the tune, the wideband sensors were having a lot of trouble getting good readings with this setup and the charts kept
coming out choppy. We spent a lot of time on it and the above is as good as we could get it.
The above pulls were all 4th gear. We did some 5th gear pulls and got 92hp with the stock mufflers. We did not do any 5th gear pulls with the Patriot but this
bike with this package has
pulled as much as 117hp in 5th in the past.
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RSD Slant 2:1
RSD Slant 2:1 result
Comparison of reference pipe to all RSD Slant 2:1
Test date: 11/17/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
The pipe reverts way down low, pulls like crazy from about 3500 to 4500, drops, and then on the very high end starts showing signs of life again.
The shape of the torque curve tells the story.
The limiter was set at 7500 as usual, but the bike was having a hard time breaking 100 with this pipe. However, the chart was still climbing. So we turned the
limiter up to 7900 for a handful of pulls and this is what it had for us. It's still climbing! Maybe if we could twist it 9000rpm it could match the Patriot on the top number.
Fit and construction are pretty good. It's industrial looking, that's for sure. All stainless, exposed welds, not polished. Collector/muffler
is held to the head pipes by springs. Nice heavy duty lower mounting bracket.Oxygen sensor placement is like the DanMoto, right out there. Easy, easy
access to them and no issues with long wideband sensors.
Not as loud as the Patriot. Really a very good sounding and good looking pipe. Performance, not so much.
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Supertrapp 2:1 Megaphone
Test date: 8/13/2013
Test bike: 2000 1200S Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SLEDGE" Head Porting Service on the original 1200S heads
HAMMER PERFORMANCE "CRUSH 600" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
HAMMER PERFORMANCE Billet Intake Manifold
Mikuni HSR42 Carburetor
Supertrapp 2:1 Megaphone & Patriot Defender Exhaust Systems as shown
Dyna 2000i Ignition System
Compression ratio is 10.9:1 and it's running on pump gas.
Comments:
As many of you know, exhaust choices are becoming scarce for solid mount
bikes. We get asked about it almost every day and we don't have a good
answer anymore. Although the Patriot is spec'ed to fit rubber mounts
only, it basically fits a solid mount with mids if you fabricate a
mounting bracket. It's one of the few systems that clears the rear brake
master cylinder. As you can see, it's well worth the effort to fit one
up if you're going for a big number. That's a pretty dramatic
difference.
When this Supertrapp pipe was bought, however, was before the Patriot was available.
Power was still climbing when we ran out of rpm's.
Some kind of a tach pickup issue at 6800-6900rpm which is why you see
the broken chart up there. Some ignitions are just difficult for the
dyno's tach pickup to read.
We also did some Supertrapp pulls at 24 discs and the bike made
about 94hp. However, we're not plotting that result because those pulls
were 5th gear and the above are 4th gear. We abandoned 5th gear testing because
the clutch was letting go on top. It was showing more power in 4th
because the clutch was holding.
Not that it has anything to do with the exhaust, but this bike is being
held back by a couple other things beyond the clutch ... the carb was
bought before the billet manifolds were developed, and as a result, it's
a bit undersized for the rest of the package. Also we need more
adjustment range in the timing (dual plugging makes the motors want less
advance and we cranked it down as far as it goes and the power was
still picking up). So those two things are also constraining the result.
We have no doubt it'd be well over 110hp if all three issues were
resolved.
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Supertrapp Supermegs
Supertrapp with closed end cap and 30 discs
Supertrapp with closed end cap and 25 discs
Supertrapp with closed end cap and 20 discs
Comparison of closed end cap with 3 different disc counts. 30 discs is pretty clearly the winner.
Supertrapp with competition end cap and 25 discs
Supertrapp with competition end cap and 20 discs
Comparison of competiton end cap with 2 different disc counts. Didn't change much. If you have to call a winner, I'd say 20 discs.
Comparison of reference pipe to all 5 tested configurations of the Supertrapp. This chart is a bit busy, hence the chart below
Comparison of reference pipe to the best closed cap result and best competition cap result
Test date: 8/11/2013 & 8/17/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
As with the other recent tests, these are all 4th gear pulls.
Installation was straightforward, and it fit well, but wideband oxygen sensors are almost impossible to fit properly..
The pipe came out of the box with 20 discs. With 30 discs, the standard included screws were
getting pretty short and there wasn't a whole lot of thread engagement,
maybe 1/4". I certainly wouldn't recommend doing 30 discs unless you get longer screws. Screws need to be stainless. Use
generous amounts of anti-seize every time you put it together (a small
amount is included with the pipe). But 30 discs is a pretty significant chunk of weight back there. I'd worry some about the screws breaking.
Quietest pipe we've tested by a wide margin. All tested configurations were pretty quiet, relatively speaking.
You don't really see the top end changing much between the different disc
counts, but you sure see it through the bottom and middle, particularly when using the closed end cap. Using the closed end cap, taking discs
out makes it go more and more toward a dual torque peak shape, with a
sag in the middle.
Using the competition end cap, the pipe didn't change much between 25 and 20 discs. Both had slightly better bottom and mid range than the best of the closed end cap tests, but gave up just
a little sliver at the very top end of the powerband.
Based on this testing, we would recommend 20 discs with the competition end cap. It perfoms well and you're not hanging a big weight off the end of the pipe.
Picture of the Supertrapp Competition end cap used for testing
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Kerker Supermegs
Kerker Supermegs result
Comparison of reference pipe to all Kerker Supermegs
Test date: 8/4/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
Unlike the Supertrapp Supermegs, this pipe uses no discs. It has a
straight through baffle. We did not try removing the baffle. Baffled,
it's not a particularly loud pipe.
Wideband sensor clearance is really tight the front and rear. They come
out at an odd angle too. We got'em on there for tuning, but honestly, if
you plan to run widebands full time, we would not recommend this pipe.
Either that or plan to relocate the sensor bungs.
The pipe gave me quite a few 98's and 99's and we beat the holy hell out
of the bike and tweaked it to death trying to get it to show 100, but
it just wouldn't do it.
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Vance & Hines Short Shots
Short Shots with standard baffle
Short Shots with no baffle
Comparison of reference pipe to both tested configurations of the Short Shots
Test date: 8/3/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
These are all 4th gear pulls. Previous tests are all 5th gear pulls. We made the change due to damaging tires.
Easy installation. The only pipe we've tested so far that allowed us to
get to the lower front head nut directly, without using a swivel adapter.
HOWEVER - there ain't no way a wideband sensor will work in the front.
Since this pipe was to be run on the dyno only, we removed the tie bar
link from the bike so that we could tune using wideband sensors. But
obviously that's not a good solution for a street ridden bike.
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D&D Bobcat
Bobcat with "Concentric" baffle
Bobcat with "Performance" baffle
Comparison of reference pipe to both tested configurations of the Bobcat
Test date: 7/13/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
Very well made pipe! Good heavy duty construction. Looks nice too.
Upswept muffler should give good cornering clearance.
Came with flanges!
Performs excellent with the concentric baffle.
Overpacked. You could drive a bus over the box and it'd hurt the bus
more than the box. Spent about a half hour carefully cutting away layers
of tape, bubble wrap, and newspaper before we ever saw the pipe.
No real issue installing. You might get into trouble with a wideband
sensor in the front, it comes real close, the motor may move enough in
street riding to make it contact the mount for the cross link.
It's a nice, high quality system, with a price tag to match.
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DanMoto Highwayman
Highwayman with included baffle
Highwayman with no baffle
Comparison of reference pipe to both tested configurations of the Highwayman
Test date: 7/13/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
With the baffle in place, the pipe doesn't offer good diffusion. It has a
reversion down low, pulls like crazy in the middle, and dies a slow
death up top. It almost looked like it was trying to pull again way up
at the tip top, and we bumped up the rev limiter a tad to give it a
chance, but it wasn't there.
Construction is, uhh, well, what's the word I'm looking for ... oh yeah,
"cheap". Where the Patriot really surprised us in a positive way when
we pulled it out of the box, looking and feeling like a pipe that should
cost twice as much, the DanMoto on the other hand looked like it was a
$219 pipe. It's thin and light. Very thin mounting bracketry too. Somewhere
along the way in our testing, one of the head pipes split along a seam. Nice.
Fit wasn't terrible, although the front head pipe comes awfully close to
the frame. You pretty much have to install the head pipes first, and
then attach the collector/muffler, which is held on by two springs.
The black finish is pretty fragile, moreso than typical of black pipes. It came out
of the wrapper with some visible marks and scratches. It also smoked
pretty good on the first warm-up, but then it stopped.
Oxygen sensor placement is odd, particularly on the rear where it's sticking almost straight up, directly behind the air cleaner. Kind of an industrial look. Easy access and no
issue with long wideband sensor.
With the baffle in place, it's not anywhere near as loud as the Patriot. Unbaffled, it's much louder.
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Vance & Hines Side Shots
V&H Side Shots result
Comparison of reference pipe to all V&H Side Shots
Test date: 1/29/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit with 30 Degree Reverse Dome Pistons
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
This was the best pull we got out of about 50 pulls, and the only one in the
103's. The little glitch at the end is probably responsible for the 103
number.
The pipe pulls hard at very low rpm, in fact we had to max out the low
rpm VE table cells in order to get the mixture close enough to give it
WOT below 3000. But then it has a bit of a reversion, followed by
another hard pull centered around 5500, and then a fall off through the
top. The torque curve tells the story.
This pipe was the most difficult to put on of any of the pipes tested so
far on this bike. The head pipes turn sharply and come in close
proximity to the heads as they come off the ports. Getting both flanges
past the heads and then over the studs was quite a trick. We said a lot
of bad words and made up a few new ones before we got it on there. Then
the rear mount holes didn't line up well either, had to loosen the
bracket from the motor and loosen the head pipe flange nuts to get that
going, then tighten everything up.
Finally, the orientation of the oxygen sensor
bungs is really bad. Forget about long wide band sensors in either one, the stock narrow band sensors barely go in.
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Rich Products Thunderheader
Rich Products Thunderheader result
Comparison of reference pipe to Thunderheader
Test date: 1/15/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with Dynojet Powervision
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
Very strong midrange pipe. Bottom and top not so much. Basically, it
doesn't have a lot of diffusion, it pulls hard over a fairly narrow
range, right in the middle. Evidence of a reversion down low.
We tuned it and beat on the bike pretty good. This is all it had for us.
Fit was really good. Nice support bracket held on by all 3 bolts, plus a
clamp bracket for the back of the pulley cover where the stock pipe
mounts. Fit up to the heads nice except it was a bitch to get the front
flange on due to the way the pipe drops away from the head rapidly. But
this is the only pipe we've tested that we could actually get a socket
onto all 4 flange nuts without a lot of gymnastics like swivel adapters
and so forth. No problem R&Ring sensors with the pipe in place. Wideband sensor (which is longer) went in but just barely.
Quality of the pipe, as it came out of the box, was so-so. Of particular
note was incomplete chroming and slight rust near where the cone was
tacked onto the megaphone and also in the collector area.
This pipe has quite a fan base, we're well aware of that. This result
pretty much confirms our past experiences dynoing bikes with this pipe.
It's a good pipe, but we'll stop short of calling it a great pipe.
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Samson Caliber (3 inch muffler)
Samson Caliber w/3 inch muffler
Comparison of reference pipe to Samson Caliber w/ 3 inch muffler
Test date: 1/8/2013
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with TTS Mastertune
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
A long time favorite on the frame mount bikes, so we were anxious to see if the rubber mount version performed well also. It does!
They actually have 3 pipes now that carry the name "Caliber".
This is the C2-731, which as of this writing can be seen
here.
This one only works with forward controls, it won't fit with mids. To use mids, you need the Powerflow III, tested previously (see below).
As compared to the Powerflow III, the rear header pipe on this one is longer, it
loops forward and around the faux timing cover.
The above pull is a bit of an anomaly. It's the only result north of the
104's that we got, the next best result was 104.4. We only got a
handful of 104's, too, just like we only got a handful of 106's with the Patriot. So in reality, the Patriot is about a 2hp stronger pipe than this one.
But this was the prettiest curve so we chose to show it.
This is a very nice pipe. Very flat torque curve, very nice looks, very
nice sound. Not as loud as the Patriot.
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Patriot Defender
Patriot Defender
Test date: 1/2/2012
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with TTS Mastertune
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
Right out of the box, with no tuning, we were banging off low 100's left and right. With fine tuning we got the
above.
This pull was with the adjustable baffle wide open. Tthis pipe is LOUD in this configuration. Noticeably louder than the Samson or Torque Hammer. Almost race bike loud.
With the baffle closed, the pipe is pretty damn quiet. But it needs a whole new map, it wouldn't hardly run with the map used for the chart
above, it was pig rich. We did not take the time to tune it and only
made a couple pulls. The top number was something like 89hp with no
tuning and it shot a lot of ducks on it's way there. Our guess is that
with tuning it'll be in the mid 90's or so. But we ran into some trouble developing the map due to the extreme reversion and abandoned the effort
Since this pipe wants such a radically different tune depending on where
you've got the baffle set, it's ideal for use with the Dynojet
Powervision which allows quick and easy tune changes.
One final note, we were pretty impressed by the overall quality of the
pipe. It's a fully welded, stepped header design, made of stainless, and
it comes with heat shields in case you don't like the gold look. The quality defies the pipe's price. No
problems with the sensor bungs and plugs were even included. Very nice
instructions in clear English (the pipe was designed in the US and is
made in Taiwan). It's a nice looking pipe.
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Twin Motorcycles Torque Hammer
Twin Motorcycles Torque Hammer with baffle
Twin Motorcycles Torque Hammer no baffle
Twin Motorcycles Torque Hammer with baffle
Comparison of reference pipe to Twin Motorcycles Torque Hammer
Test date: 12/19/2012
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with TTS Mastertune
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
This pipe with the baffle pulls very hard down low and very hard up high, with something of a sag in between. Remove the baffle and the result inverts: it pulls hard in the middle but
less so down low and up high.
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Samson Powerflow III
Samson Powerflow III
Comparison of reference pipe to Samson Powerflow III
Test date: 12/15/2012
Test bike: 2007 XL883 Sportster equipped as follows:
HAMMER PERFORMANCE Bolt-on 1250 Kit
HAMMER PERFORMANCE "SMASH" Head Porting Service on the original 883 heads
HAMMER PERFORMANCE "IMPACT 560" Cams
HAMMER PERFORMANCE Air Hammer Air Cleaner
Tuned with TTS Mastertune
Compression ratio is 10.5:1 and it's running on pump gas.
Comments:
If you want to run a 2:1 Samson with mid controls, this is your only option. This is the C2-331 shown
here.
We tried and tried to get 100hp out of this pipe, but it just didn't have it for us. This was the best she could do.
It's very strong on the bottom, but not so much on top. Not a race pipe, not a dyno shootout pipe, but a very nice street pipe.
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Frequently Asked Questions
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Can you recommend an exhaust for me?
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There are a lot of considerations when you buy an exhaust. High on the list for many people are the looks and the sound. These are not things we can evaluate for you. All we
can really do is show you how they perform, and make comments on things like ease of installation and the apparent quality of the pieces. At the end of the day, it's up to you
to make an overall evaluation based on all of these things. Our role is to provide the performance data and other comments, not to tell you what best suits you.
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Where can I get a Patriot Defender Exhaust?
- Unfortunately, the Patriot exhaust that's used as our reference pipe was discontinued. We do not have any available and as far as we know, none are available anywhere. We
don't have any used ones available either, sorry.
- However, we've been told that a new version of the Patriot Defender is coming out soon. We are hopeful it will perform well and we'll be testing it the moment we get our hands on it.
So watch this page for that test. We do not have an availability date, sorry.
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I'm interested in a pipe that's not tested on your page. Can you tell me how it will perform?
- What's posted on this page is the sum total of all test data we have to share.
- It's impossible to tell how a pipe will perform based on it's looks, and be very skeptical of anyone who says they can do this. Pipe design is a very
complex subject. Even very subtle changes can make all the difference in the world in the results. Many aspects of the design that affect performance aren't
even visible from outside a pipe, for example the baffle design. Speculating on how a pipe will perform without even testing it is just all-around a bad idea.
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