Comparison of Various Exhaust Systems to the Vance and Hines Widow 2-1-2 on the XR1200

This data shows a comparison between a number of the better performing aftermarket replacement exhaust systems for the XR1200, and the Vance and Hines Widow 2-1-2 exhaust system. 
The data was collected from a modified XR1200 motor capable of producing nominally 100 SAE HP and 90 ft-lbs of TQ.  The increased power output of this engine highlights strengths and weaknesses in the design of the exhaust systems - which are not necessarily visible with a tuned stock XR1200 motor with a typical max of 85 - 90 HP.

Dyno Graphs

The following dyno runs were all performed on the same Dynojet 250 dynamometer.  Although not possible to perform on a single day, the graphs are all SAE corrected and whether conditions were similar.
The engine is a 1200 cc XR1200 motor with Zippers 575XR cams, Wiseco pistons, a 0.020 metal layered head gasket, and CNC ported heads (by Zippers).  Custom length one-piece pushrods are used.  The airbox uses a custom oversized K&N air filter and internal obstructions in the airbox have been removed to improve air flow.  The head breathers and crankcase breather have been externally routed.  Primary gearing has been changed from 34-57 to 38-57.  The 28 tooth transmission pulley has been replaced with a 29.  The rear 180 stock Dunlop tire has been replaced with the 190 racing Dunlop tire.  (5th gear gearing for the dyno runs is altered from 4.071 to 3.414.)  There are a few other minor engine tweaks, but these are the more major.
Before the engine build the peak power of the tuned engine was about 70 ft-lbs of TQ and 85 HP (with stock gearing).  After the build, depending upon the intake and exhaust configuration, the engine is capable of about 90 ft-lbs of TQ and 100 HP (with its altered gearing).
All dyno graphs for all exhaust systems were done with this engine build.

OEM HD Exhaust System for XR1200 vs V&H Widow 2-1-2

The first dyno graph shows a comparison between the XR1200 with an unmodified OEM exhaust system (RED) against the Vance and Hines Widow 2-1-2 (BLUE).

Unmodified OEM XR1200 Exhaust to V&H Widow 2-1-2

D&D 2-into-1 Header with Special Exhaust Can vs V&H Widow 2-1-2

This graph compares the D&D exhaust header from their 2-into-1 Concentric Baffle exhaust system for the XR1200 (RED), and the Vance and Hines Widow 2-1-2 (BLUE).
In early testing of the complete D&D Concentric baffle 2-into-1 exhaust system, it was determined that the Concentric Baffle exhaust can, was not a peak performer.  However, the D&D 2-into-1 exhaust header for the XR1200 was well-designed.  Therefore the Concentric Baffle exhaust can was swapped for a special exhaust can from another manufacturer.  This graph therefore shows what is possible with the D&D 2-into-1 header with another exhaust can - which is better than the production D&D Concentric Baffle exhaust system.  The D&D Concentric Baffle exhaust system would post lower numbers.
Unfortunately, the only dyno graphs that I have comparing the different trials of the complete D&D system are from another dyno, and not directly comparable to this one.  And, I no longer have access to the D&D Concentric Baffle exhaust can, to do a direct comparison of production systems.
This graph does, however, show the strong performance of the V&H system, against a variant of the D&D system which performs better than the D&D production model.

D&D with Special Exhaust Can to V&H Widow 2-1-2

JOEP Special 2-into-1 Exhaust vs V&H Widow 2-1-2

This graph shows a comparison between the JOEP Special 2-into-1 exhaust sytem (BLUE), and the Vance and Hines Widow 2-1-2 (RED).  The JOEP Special is a limited production exhaust system based on the HD OEM headers.  It combines a short collector pipe with the headers to make a fairly effective drag-style exhaust for the XR1200.

D&D with Special Exhaust Can to V&H Widow 2-1-2

Termignoni Trophy Race 2-1-2 Exhaust System vs V&H Widow 2-1-2

The graph shows a comparison between the Termignoni 2-1-2 Trophy Race exhaust system  (RED and BLACK), against the Vance and Hines Widow 2-1-2 (BLUE).
I like the appearance of the Termignoni exhaust system, but was disappointed by its mid-range performance.  I wondered if it was possible to do some tuning on the Termignoni 2-1-2 to boost its mid-range TQ.  As an initial attempt to see if tuning would have any impact, I ran a comparison of the Termignoni exhaust system as produced (RED), against the Termignoni system with the lower exhaust can fully plugged at its outlet (BLACK).  The end result is a shift in the TQ produced, but it does not appear to be enough to allow the Termignoni 2-1-2 exhaust to outperform the V&H in the mid-band.
This graph shows the Termignoni, without its "db Killer" noise silencers (RED), vs the same Termignoni exhaust with the lower exhaust can capped (BLACK), vs the V&H Widow 2-1-2 (BLUE).

Termignoni 2-1-1 Trophy Race Pipe to V&H Widow 2-1-2

Torque Hammer 2-into-1 Exhaust System vs V&H Widow 2-1-2

The graph shows a comparison between the Torque Hammer 2-into-1 exhaust system  (RED and BLACK) against the Vance and Hines Widow 2-1-2 (BLUE).
The Torque Hammer exhaust system is a production exhaust system for the XR1200, custom designed and manufactured by Twin Performance of the Netherlands.  Since the Torque Hammer has removeable noise baffles (silencers), this graphs shows a comparison of the Torque Hammer with its noise silencing baffles (RED), against the Torque Hammer without its noise silencers (BLACK), against the V&H Widow 2-1-2 (BLUE).

Torque Hammer (by Twin Performance of the Netherlands) to V&H Widow 2-1-2

Effects of Intake Tuning with the V&H Widow 2-1-2 Exhaust

The next graph is a comparison of different intake configurations, using the V&H Widow 2-1-2 exhaust system as the baseline exhaust. 
The graph shows a comparison between the XR1200 with its Airbox intake (BLUE), against the same engine and exhaust configuration but replacing the Airbox with an approximately 4" long, 2" diameter elbow  (RED and BLACK).  Two runs are shown for the tuned intake, just because this was the first tuning configuration that let this 1200 cc engine build break 100 SAE HP. 
The intake elbow is characteristic of the type of tube that might be used with a cone air filter.  The same V&H Widow 2-1-2 exhaust was used for all runs, an the intake configuration was the only thing changed.

V&H with Intake Mod to V&H with OEM Airbox


At about 21.75 lbs (with mounting brackets), the black street version of the Widow 2-1-2 is not the lightest exhaust for the XR1200.  But, when first installed it is good looking, has good ground clearance, and does have the best performance characteristics of all pipes tested to date.
Issues noted with the black street version of the Widow 2-1-2 were related to installation and fitment.  This black street version of the V&H exhaust was installed on a XR1200 that has Ohlins external reservoir shock absorbers and riser mounting blocks for the rear shock absorbers.  The passenger (rear) footpegs and stock exhaust mounting points had also been removed. 
The first installation problem was the interference between the Widow 2-1-2 exhaust can mounting plate and the rear shock absorbers.  A custom bracket was made to eliminate the interference and hang the exhaust cans from the rearward OEM exhaust hanger used for the back of the stock exhaust cans.
The next problem was that the front lower exhaust bracket that attaches the headers to the bottom of the engine was too short.  This caused the exhaust headers to be pulled inward toward the side of the bike and place stress on the exhaust flange mounting studs on the heads.  It also caused the exhaust tube to contact the rear swingarm.  A longer standoff bracket was fabricated at a length that did not put a bind on the cylinder head exhaust flanges, and provide clearance for the rear swingarm.  Even with this modification though, the swingarm still contacted the exhaust pipe when the rear shocks were fully extended.
Lastly, the angle of the front O2 sensor bung placed the sensor directly over the lowrer exhaust flange nut.  This made it difficult to tighten and torque the exhaust stud.While there was no interference, it made installing and tightening the O2 sensor difficult.  The horn was temporarily removed during installation to gain some clearance.  Also, the downward angle of the rear O2 sensor makes installation of the sensor difficult.  A slightly more upward (and perhaps rearward) sensor angle would have made this sensor easier to install and remove and taken stress of its wire.
The finish of the black V&H Widow 2-1-2 exhaust system also is not ideal. The black coating is easily marred, and is subject to staining from oils or water spotting.  While I did not have the exhaust on the bike long enough to experience rusting, other users have complained of premature rusting of the system, and overall discoloration of the coating.
The V&H Widow 2-1-2 is one of the best performing exhaust systems for the XR1200.  Although not a strong performer below 3,000 rpm, the XR1200 naturally likes to be riddent from 3,500 to 6,000 (or 7,000) rpm.  It produces excellent mid-range power, and allows for some of the best peak HP figures seen.
Considering the nominally 22 lb weight of the black street version of the Widow (compared to about half that for other stainless XR1200 race pipes), and the fitment issues of the street version, I'd like to run a stainless race pipe to confirm its performance meets or exceeds the street pipe, while improving fitment and weight. 
Also, I'd like to do some more minor exhaust tuning with the V&H pipe to see if low end TQ can be improved upon while keeping the strong mid-range.
And finally, I'd like to do some further intake tuning experiments while running the V&H pipe, to come up with a 1200 cc XR1200 engine build that hits 100 HP and keeps a broad 90 ft-lb TQ band.

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