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Black Widow Decat Race Header Install & Review


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Black Widow Decat Race Header




Black Friday strikes with a Black Widow Decat Race Header to mate up with my MIVV Dakar high mount exhaust arriving in just 5 days from England. The header + air filter box de-snorkel necessitate another Black Friday purchase of a 2WheelDynoWorks mail in ecu flash to ensure correct fuel & ignition mapping. This years mail in ecu flash Black Friday sale ($225 US or $313 CDN) is for the entire month of Nov & can be done via mail, drop off or ride in at their shop just east of Seattle Wa, USA. Kudo's to them for having no time limit on when to have the ecu flashed, so will be able to ride down in the spring when the bike is insured.
The Black Widow down pipe o.d. is 37.2mm vs the oem's 35mm, with a 42mm o.d. collector/connector pipe, 1mm wall thickness & is 54%  or 1.5 kg lighter than the oem. Quality & fitment looks good across the board with supplied port gaskets thicker than the oems, 2 silicon covered springs, spring tool & stainless collector to under motor frame bolt & packaged nicely to prevent damage in shipment...great value at $149 BPD + $50 BPD shipping equating to $353 Cdn.
From the Black Widow Website


Fits:  Yamaha XTZ 700 Tenere 2021-2023 models.
         Yamaha XTZ 700 Tenere Rally Edition 2021-2023.
         Yamaha XTZ 700 Tenere World Raid 2021-2023.
  • Replaces your standard oem front pipes and will fit your oem silencer and our own Black Widow Silencers.
  • Hand welded and made from 304 grade lightweight stainless steel.
  • Does away with the cumbersome catalytic box that is part of your original exhaust.
  • Improves both power and fuel economy.
  • These weigh 1.85kg compared to the standard oem weight of 3.40kg. Saving over 1.5 kilos.
  • By far these are the best power gain and weight saving part you can fit to your XT700.
  • These pipes come with the threaded hole for your original lambda sensor, allowing you to keep the benefit of your bikes engine management system.
  • Please note emissions are not tested on motorcycles in the UK for the MOT.
  • 2 engine port gaskets included.
  • 2 Year Unlimited Mileage Warranty.


Oem Header vs Black Widow
Installed on 2021 Tenere 700
Detailed 8 page instructions (see below) are provided + an O2 sensor extension cable needed for Euro 5 bikes with  the forward mounted catalytic converter (both Euro 4 & 5 use the same header collector with O2 sensor bung located in the same position as Euro 4 bikes with the cat mounted under the motor). Each header pipe & corresponding collector inlet are labelled #1 & #2 to facilitate correct positioning. The Black Widow header pipe port flange is a square edge design vs the oem tapered design that does not fully seat against the thinner oem gasket because of interference with the engine port casting mandating use of the supplied port gaskets that are approx 1.5x thicker than the oem...other than that everything aligns & bolts up. The supplied exhaust paste eases pipe fitment & help seal the joints (clean excess paste off exterior surfaces quickly as it is difficult once dried).
Tech Tips: Install the #2 header down pipe 1st (right side), otherwise access to the bolts is tight with #1 installed 1st. Do a dry fit with all bolts slightly loose, then disassemble, apply the exhaust paste, reconnect, wiggle the entire assembly in all directions to ensure correct alignment, that the down pipes are fully seated in the collector & that the collector mid pipe mount sits square to the oem under motor mounting bracket, install the 2 springs, then tighten all bolts hand snug & torque the 4 port & 1 collector mount bolts to 20 Nm or 15 lb-ft. I bent the supplied springs open hook ends more together & positioned the open end facing the pipes to prevent them from rubbing on them.


The Black Widow collector outlet pipe is the same diameter as the oem facilitating fitment of the oem & most aftermarket exhausts.  The MIVV Dakar high mount exhaust aligned up just as it did with the oem header assembly...I was able to slightly increase clearances with the swingarm & unused oem exhaust hanger assembly. 


Note: The outlet pipe of the Black Widow collector does not have a flange or pipe flare to act as a stop for the MIVV pipe, allowing the female end of the MIVV exhaust to slide further up the male end of the Black Widow pipe than needed...which permits some forward & back movement of the rear portion of the exhaust that was not available with the oem header/cat assembly that may be helpful for fine tuning with clearances/positioning of the muffler assembly.
Down pipes clear AXP Skid Plate
What Does it Feel & Sound Like?
As the bike is not insured until spring I snuck out for a short ride around the neighbourhood for a sampler & noted a subtle, but discernible smoother throttle response, freer revving motor & fuller exhaust tone that is slightly louder with a little more bark & authority from behind & when aggressively blipping the throttle...somewhat similar to before installing a custom made db killer with spark arrestor in the MIVV Dakar muffler resulting in slightly muted output taking the edge off producing a pleasant & neighbourhood friendly output...at idle & steady rpm from on or beside the bike it's hardly any change from before being more of a slight change in character than loudness. As similarly observed with my 2014 Yamaha Super Tenere 1200 ES when installing an Arrow decat header, the T7 Black Widow decat header has resulted in subtle vs significant or dramatic change in exhaust sound.
 A video of my 2021 Canadian Tenere 700 with Black Widow Decat Race header, MIVV Dakar high exhaust w/custom db killer & spark arrestor, de-snorkel air box, FunnelWebFilters air box lid pre-filter, Guglatech Ultra4 main filter & iridium spark plugs can be viewed via this link here. Recorded exhaust sounds are challenging to capture with full effect, the video is best heard with headphones or full speaker systems w/sub woofer.
Other Performance Related Upgrades
Other recent performance related projects include changing to Iridium spark plugs...see blog post here & an ecu flash tune by 2WheelDynoWorks...see blog post here.
Black Widow Decat Race Header Installation Instructions
Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_1.jpg Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_2.jpg
Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_3.jpg Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_4.jpg
Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_5.jpg Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_6.jpg
Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_7.jpg Black%20Widow%20Decat%20Race%20Header%20Instructions_Page_8.jpg
Edited by prowlnS10
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