Tenere 700: MIVV Dakar Exhaust & Carbon Heat Shield + MIVV db Killer with Custom Insert Extension
MIVV Dakar Y.064.LDKX Exhaust + Carbon Heat Shield ACC.80.0
Why a New Exhaust?
Yamaha opted for Dakar inspired styling & cost savings vs function with the design & location of the oem muffler for the Tenere 700 that positions it precariously low & outside the swingarm, attached to a welded on vs bolt on hanger that easily bends pushing the muffler into the aluminum swingarm with the slightest provocation (there have even been reports that some damaged bikes in the USA have been written off by insurance citing a bent frame). See my blog article here for additional info on the swingarm/muffler issue & several aftermarket T7 exhaust options. The oem wide muffler positioning also complicates the use of some soft bag & rackless systems & clearance with the hot muffler plus mandates that many luggage rack systems be detrimentally far away from the center line of the bike, adding unnecessary width & undesirable handling dynamics at the back end. Despite much feedback from the T7 community & an opportunity to rectify these issues with the redesigned World Raid model in 2022, Yamaha has retained the original design.
My primary motivations were focused on improved packaging that eliminate the oem design flaws & improve handling dynamics, particularly when loaded up with luggage. My mid 60s ears & mind prioritize loud pipes & hp gains on a T7 at the opposite end of the spectrum from comfort & a skill set commensurate with remaining as unscathed as possible for the remainder of my riding career...but a little improvement in the "quality" of the auditory experience is welcome😀.
I wanted a tucked in, high mount exhaust that retained the welded on oem exhaust hanger vs being cut off & the oem footpeg hanger. Dominator, Huzar, HP Corsa, MIVV & SC Projects provide bolt on systems that relocate the muffler high & tucked in via a custom bend mid-pipe that meets that criteria...but some position the hot muffler exhaust directly onto the oem turn signals & some aftermarket tail tidy signal locations...so do your due diligence before purchase. Camel ADV was an early adopter of a popular repositioned high mount exhaust system that remains faithful to the Dakar look that addressed the easily bent hanger & muffler hitting/damaging the swing arm problem & recently added an Enduro Bend that positions the muffler more parallel to the rear side panel...but both necessitate cutting the exhaust hanger (Camel provides a template & hanger clamp) & the Enduro Bend is not compatible with the foot peg hanger & imho has an ugly near 90 degree bend of the mid-pipe connector at the swingarm + both styles do not relocate the muffler much more inward than the oem. If Yamaha had utilized a bolt on hanger, removal would create room for a longer muffler with more volume (see pic further below for MIVV Dakar muffler specs/dimensions).
Unboxed
MIVV Dakar Exhaust
I opted for the stainless MIVV Dakar Exhaust Y.064.LDKX (a black Y.064.LDKB muffler is available) during Black Friday sales in November 2022 from EM Moto in Italy including their Carbon Heat Shield ACC.080.0 & international shipping for $401 Euro or about $525 Canadian (no Canadian tax or brokerage fee was charged upon delivery by DHL Express). Note that MIVV sells the Euro 4/5 compliant db killer 50.DK.181.0 separately & that it does not include any spark arrestor component. Delivery took much longer than the 15 business days promised to ship & did not arrive until early January 2023. MIVV claims 2.1 kg/4.63 lbs for their Dakar system vs the oem muffler/mid-pipe assembly at 4.8 kg/10.58 lbs or 2.7 kg/5.95 lbs lighter and +2.20 hp & +1.40 Nm torque (see dyno graph below).
Preliminary fitment on my 2021 Canadian T7
Quality of the stainless mid-pipe & welds is average with some visible flaws, but overall ok...the i.d of the mid-pipe connector to the catalytic converter outlet pipe is smaller than the oem equivalent part, eliminating the use of the oem gasket & necessitating a smaller diameter included clamp...wall thickness is 1 mm...clearance between the bottom of the swingarm (+ nearby swingarm rubber plug) & the exhaust hanger with the connector pipe can be tweaked by rotating the connector pipe producing a maximum of 10 mm (0.4") clearance for both locations simultaneously (larger gaps can be obtained at 1 location at the expense of the other), which is 1/2 of the 20 mm (0.78") MIVV references for recommended clearance of the exhaust system in the supplied documentation...no clamp is provided for the 55 mm (2.16") i.d. muffler to mid-pipe connection, but is a snug slide on fit with over 2.54 cm (1") of overlap, but only has 1 spring/clasp instead of the typical 2...does not ship with a db killer or integrated heat shield...all cost saving measures...but can't really complain, as it is very good value & overall MIVV delivers a comprehensive good looking design/system & based on other's videos is not too loud producing a pleasant deeper tone than oem muffler, that imho emulates what Yamaha should have adopted as oem fitment. I particularly like that MIVV kept the connector pipe & muffler in line vs angling the muffler up at the back, adopted one of the nicer bends to clear the swingarm, retains use of the footpeg & exhaust hangers, positions the output of the muffler a little lower than most of the competition & utilizes a solid stainless mounting plate that bolts to the muffler for a cleaner look vs a clamp...& bolts to the frame for more rigid mounting vs the exhaust hanger.
10 mm/0.4" clearance between connector pipe & swing arm & exhaust hanger on my 2021 Euro 4 spec Canadian T7
The Carbon heat shield specs M6 bolts for the clamps, but the bolt threads are 1 size smaller (M5) than the provided M6 bolts...aargh👎 Apparently other recent buyers of the MIVV Carbon Heat Shield also had the same issue of incorrect bolt thread size on the clamps.
UPDATE Feb 2023: I emailed both MIVV & EM Moto of the issue 1 week ago & only had a reply from EM Moto so far, who will mail 2 correctly sized bolts as warranty...they never arrived so bought my own locally at Pacific Fasteners. The stainless muffler seems substantial & aesthetically pleasing...a straight thru flow design, but does not ship with a db killer, which is optional...the sturdy stainless muffler mounting plate that bolts to the muffler & the oem wheel well fender bolts will necessitate some mods to either my existing luggage rack mount & custom fender insert under the rear fender, or a new custom mounting plate to connect securely to the bike + the right DirtRacks luggage rack will need the forward mounting tube cut off the rack & repositioned/rewelded to permit tucking the rack in closer to the centerline of the bike (like I did to the left rack last year) & bolt directly to the oem frame footpeg hanger bolt threads without needing the supplied spacer which currently has clearance issues with the mid-pipe.
Connector pipe bend is compatible with oem footpeg hanger
The MIVV assembly tucks in tight to the bike out of harms way, positions the muffler outlet pipe below my Camel ADV Tail Tidy/Cyclops ADV LED turn signals, retains the oem exhaust hanger & use of the right footpeg hanger, permits narrower fitting side luggage racks & looks & sounds good to my eyes & ears 👍 As with most aftermarket mufflers the MIVV looks to be compatible with oem ecu programming, generally not requiring a flash, however, when used in combination with other modifications &/or compliance with various homologation, noise & off-road use (spark arrestor) regulations may require further investigation...do your due diligence to ensure compliance & responsible use in your region. If anyone has come across an off the shelf spark arrestor that fits the MIVV, let me know...thx.
MIVV Dakar tucks in close to the center line of the bike out of harms way
Final Fitment w/Custom Muffler Mounting Bracket & MIVV Carbon Heat Shield (March 2023)
Mid-pipe o.d Dimensions
The MIVV Dakar mid-pipe progressively increases in diameter from 48.5 mm just after connection with the oem header pipe (the 44.4 mm diameter connection is smaller than the oem equivalent part, eliminating the use of the oem gasket & necessitating a smaller diameter included clamp) to 55 mm at the muffler connection.
My set up required a custom muffler mounting bracket because access to the under fender oem fender assembly mounting bolts was blocked by my existing luggage rack mount & custom fender insert. I used 1/8" or 3.175 mm thick aluminum box stock & added a shorter 2nd inside corner piece to strengthen the 90 degree bend while keeping the extended portion of the full length bracket single layer & shaped to the muffler curvature where it attaches to the muffler for maximum clearance of the tire at full travel...all clear coated for extra measure. The MIVV mounting plate measures 150 mm from the top of its forward mount tab to the center of the forward muffler mounting bolt so made a custom muffler mount that bolts to a different location but equates to the same muffler vertical position (i.e. 150 mm from the forward wheel well mounting point that the MIVV mount uses to the center of my mount's forward muffler mounting bolt). The luggage rack under fender cross brace bolts utilized for my custom mounting plate are the same size as those utilized by the MIVV mounting bracket.
I used Permatex Red High Temperature RTV Gasket Maker for the pipe connections & the mounting bracket surface where it interfaces with the muffler bolt location for improved vibration/heat transfer isolation.
What Does it Sound Like?
It has a somewhat louder, deeper/fuller, more baritone sound than the oem...overall more pleasant, but will not know if too loud for my ears until the bike is insured for this season...but also has an annoying metallic chuff/rattle upon quick blips/release of the throttle that is not present during steady revs...it seems to be associated with rapid pressure changes of the outlet gasses at the tail pipe...perhaps a result of the tail pipe insert being slightly loose (held in place by 1 rivet) or a function of it's 5 cm or 1.9" length that barely protrudes into the interior of the muffler (the MIVV db killer is about 3x as long)...here is a brief sound byte that doesn't quite do it justice:
I won't have my bike insured for a few months, but this video posted by Windblown provides a nice sound byte of the MIVV Dakar system in use.
April 10/23 UPDATE - Clearance Issues with Swingarm Brake Hose/Cable Guide During Full Range of Travel
While mounting a new rear tire I decided to check for swingarm & tire clearance with the MIVV set up by disconnecting the shock linkage & measuring the swingarm travel & discovered that the raised forward part of the swingarm brake hose/cable guide made contact with the MIVV mid-pipe @ 165 mm of travel (as measured perpendicular to the ground at the axle relative to the swingarm being fully extended with the shock linkage connected & bike on the center stand)...with the guide removed travel increased to 180 mm before contact with the swingarm...not good as the T7 has 200 mm of rear wheel travel!
NOTE: I did not use the MIVV supplied muffler mount that measures 150 mm from the top of its forward mount tab to the center of the forward muffler mounting bolt, so made a custom muffler mount that bolts to a different location but equates to the same muffler vertical position (i.e. 150 mm from the forward wheel well mounting point that the MIVV mount uses to the center of my mount's forward muffler mounting bolt)...the only other variance is that I have a Camel Adventure Tail Tidy vs the oem assembly that may alter the mounting plate vertical position of few mm relative to the oem fender assembly.
After modifying the brake hose/cable guide, angling my custom mount inwards slightly, raising the muffler mounting location on my custom mount 10 mm (now 140 mm vs 150 mm spacing from the top of the forward mount tab to the center of the forward muffler mounting bolt) combined with loosening the mid-pipe clamp & adjusting the pipe for max height it now has 205 mm clearance with the modified guide & 215 mm of travel with it removed before contact (I may remove it & use zip ties or cut off the front portion)...but now have only 4 mm clearance between the mid-pipe & the oem muffler hanger. There was about 12 mm of clearance between the new Motoz Rallz 150/70 18 tire side blocks & my custom muffler mount.
There have been several other T7 owners who have experienced similar limited horizontal clearance with the swingarm of at least half the 20 mm recommended by MIVV in their installation instructions...but, so far, have only heard of 1 other MIVV Dakar user commenting on vertical clearance issues with the swingarm full range of travel on his Euro 5 forward catalytic converter location (vs under the motor) 2022 Rally model....interestingly his horizontal clearance was only 1 or 2 mm while myself & others with Euro 4 bikes w/under motor cats have around 10 mm...which makes me wonder if the Euro 5 location/position/angle of the header outlet pipe where it connects to the mid-pipe might be slightly different than the Euro 4 model with cat located under the motor, which is probably not an issue with the oem exhaust...or perhaps its just variances in manufacturing tolerances.
UPDATE April 18/23 - A revised MIVV Dakar mid-pipe has surfaced, but still has horizontal clearance issues with the swingarm & now the oem foot peg hanger...it seems an uncharacteristic fugly misstep by the usually stylish conscious Italians!
Based on my experience & that of others it seems that MIVV may not have fully developed their mid-pipe for adequate horizontal & vertical clearances with the swingarm & now seem to have re-designed the mid-pipe in an effort to address these issues. This new design, imho, seems an unnecessary departure from the attractive lines & larger diameter pipe for the 1st 2/3 of the original that may create new clearances issues with the foot peg hanger, far less appealing aesthetics that seems to fall short of fully correcting the horizontal clearance issue & may reduce flow & performance...when all that may be needed is to shorten the distance from the front mid-pipe connector to the 1st bend by about 10 mm, extend the distance to 2nd bend by about 10 mm & the distance to the 3rd bend a few millimeters to improve clearances with the swingarm in the static position, at full travel & the oem exhaust hanger. MIVV has yet to update their website.
Pic from Diezel @ tenere700.net
The gen 2 mid-pipe is shaped different with smaller diameter pipe in the 1st 2/3.
Pic from Mark Oppelt @ Yamaha Tenere 700
July 06, 2024 Update MIVV DB Killer 50.DK.187.0
While really preferring the overall deeper, more robust sound of the MIVV exhaust over the oem I find it a little too load & robust with some drone at some mid-rpm levels so installed the MIVV db killer insert which is not included with the muffler. MIVV does not publish a db attenuation rating for it, but based on my experience on my bike I would speculate that it provides ~1-2 db of reduction, as it's effect was noticeable, but more on the mild side.
MIVV end cap supplied with Dakar muffler: It required drilling out the rivet attaching the MIVV tail pipe insert that only extends the length the angled tail pipe extension (45 mm or 1.8") with 35 mm or 1.375" o.d. & 33 mm or 1.3" i.d.
July 30, 2026 Update MIVV DB Killer 50.DK.187.0 + Custom Insert Extension to Tune Output
The high mount MIVV Dakar muffler & mid-pipe was designed & tuned for a sporty/aggresive tone & loudness vs stock, even with the matching MIVV db killer installed. I want to achieve improved sound quality foremost & ~1-2 db reduction in volume for my 68 year old ears (deeper, less aggresive/loud tone & reduced droning at mid rpms for everyday riding & touring).
I researched 2 options:
- Replace the MIVV Dakar muffler with a higher quality muffler with larger volume & more sophisticated acoustic tuning & db killer design that would fit the MIVV 55 mm OD mid-pipe & high mount location, of which, Wings is willing to sell their Tenere 700 muffler fitted with a larger 55 mm intake (42 mm is standard) to mate with the MIVV mid-pipe (a rather pricey option at $583 Cdn + $79 shipping totaling approx $709 Cdn delivered including Tax & brokerage fees, notwithstanding the top teir quality titanium construction & tuning philosophy that produces a very pleasant & deep output);
- Tune the MIVV Dakar muffler using a custom made insert extension added to the MIVV db killer, with the Wings option as plan B if the MIVV can't be tuned to satisfaction.
The MIVV Dakar db killer incorporates 34 mm OD/32 mm ID, 1 mm wall thickness tubing with a 30 to 35 degree smooth continuous bend terminating in a downward facing slash cut open end intake & 95 mm length inside the muffler (effective length for accoustics) + 20 mm tailpipe for a total length of 115 mm (effective length for fluid & hydraulic dynamics) measured at the center line. The body of the muffler is oval shaped ~300 mm long x 92 mm wide (exterior dimensions), which, when combined with the db killer tubing bend, the insert 45 degree bend being very close to the bottom of the muffler interior perforated core restricts use of a larger ID extension tube that fits over the db killer tubing creating clearance issues when inserting it past the down turned outlet & with the muffler interior, so opted to source a 2 pack 32 mm OD/29 mm ID 1.5 mm wall thickness stainless steel 45 degree bend pipe to fit inside the db killer via Amazon.
ChatGPT proved useful for analyzing db killer designs utilized by several established motorcycle muffler manufactures & determing which design elements would produce my desired accoustic outcome while preserving appropriate exhaust pressure & throttle response for the T7's CP2 motor when used in conjuction with the MIVV curved db killer & the 45 degree bend stainless extension pipe inserted into the inlet end of the db killer by analysis of the following:
- fluid & hydraulic dynamics (flow/back pressure/pumping loss), accoustic tuning inside a straight-through muffler & overall exhaust system resonance;
- calculate the effective area of the 2 tubes (db killer & custom extension) that have different shapes, inside diameter & lengths, analyze their impact on accoustic tuning & fluid/hydraulic dynamics;
- determine optimized type/shape of intake opening of the extension insert;
- determine number, size, shape, location & orientation of holes/slots drilled in the extension & their impact on tuning optimal accoustic characterics & exhaust pressure for the CP2 motor;
- pros/cons of incorporating #30 stainless mesh screen (approved for use in spark arrestors by USFS) over the inlet &/or drilled holes;
The flow direction of the exhaust gases 1st entering into a smaller 29 mm ID inlet extension, then into the larger 32 mm ID MIVV db killer outlet & then to atmosphere (creating a 2 stage diffuser) is considered beneficial to flow dynamics via slowing gas velocity & when combined with the 2 bends & overall length of the combined inserts is largely responsible for the changes in accoustic character of the muffler output. MIVV incorporated the same fluid & hydraulic dynamics principal with the original Dakar high mount mid-pipe I have, which increases in 6 steps from 44.4 mm OD at the connection to the header to 55 mm OD at the muffler inlet connection, progressively slowing exhaust gas velocity.
I started with the longest length of extension tubing (105 mm of which 20 mm fits inside the MIVV db killer) that physicaly fit inside the muffler when attached to the MIVV db killer for a combined effective interior length of 180 mm & 200 mm total length measured along the centerline of the tubes, terminating in an open end inlet close to the top of the interor of the perforated muffler core ~120 mm into the 300 mm length of the MIVV Dakar muffler. Their combined shape forms an abreviated sign-wave shape that creates a long, non-line of sight accoustic path forcing the sound waves to change direction 2 times vs a straight pipe, attenuating the higher frequencies & harshness/raspiness inherent in the MIVV Dakar output. This produced a more prefered deeper, muted tone across the rpm band with less edge, raspiness & drone, but did increase back pressure slowing throttle response & acceleration...not surprising given the longer than normal db killer length & 21.76 % reduction in cross-sectional area of the narrower insert extension vs the MIVV db killer.
Hoping to preserve as much of the newly achieved accoustic tone, quality & output levels as possible I opted to tune out the increased restriction in flow via drilling strategically sized, shaped & placed holes/slots in the insert extension (locally reducing static pressur via controlled pressure bleed off) vs shortening the extension, which would have a greater impact on accoustic tuning, resulting in a higher probability of moving the sound back toward the oem MIVV tune. ChatGPT suggested a progressive methodology of starting with small 4.0 mm holes or slots that could be progressively increased if needed & analized several hole configurations & placements via trial & error.
My 1st prototype incorporated 4.5 mm x 7 mm elongated radiused slots in the insert upstream of the 45 degree bend which, starting with just 2 opposing holes placed 40 mm from the insert inlet at 3 & 6 o/clock improved throttle response & acceleration without much change in accoutic character. I added 2 more identical size/shape slots at 12 & 6 o/clock placed 25 mm from the insert inlet (the separation of the holes creates a 2 stage diffuser). Which resulted in crisper throttle response & mid-range that pulls strong in the lower 3 gears & accelerates quicker across most of the entire rpm band...but did introduce a slight bit of raspiness back into the mix, hinting of an angrier tone when on the gas while being slightly more muted overall. In terms of loudness it likely hit my expectation of 1-2 db perceived attenuation.
In an effort to claw back some of the raspiness that had crept into prototype 1, while preserving the crisp throttle response & motor performance, I wanted to experiment with placing some of the bleed off holes/slots downstream of the 45 degree bend but before the overlap of the insert & MIVV db killer with my 2nd prototype to test the theory of if the system could be tuned for accoustics & pressure independently & if the newly added smaller diameter tubing was responsible for the majority of change in accoustic character & attenuation or if the bleed off holes produced equal emphasis. Through a variety of experimenting with blocking off certain holes or all of them it appears that the additional tubing carries the majority workload for both accoustic & pressure changes with the holes predominantly tuning bleed-off pressure for my set-up. Tuning changes via holes/slots produce more impact under throttle/load than at idle, which makes sense given the lower gas velocity at idle. Without the benefit of a dyno, pressure & accoustic gauges the fine tuning is by 'old school seat of the pants feel' regarding throttle response, acceleration, feel of the motor & by ear that involves a repetitive process of make a change, ride & evalutate...continuing to make incrimental changes followed by more ride & evaluation until a balance of bike performance & accoustic character has been acheived.
Prototype #2 started with a radial pattern (provides more even bleed-off into the muffler core) of four 4 mm holes at 2, 4, 8 & 10 o/clock spaced 10 mm apart axialy starting 10 mm upstream from the 45 degree bend ending 25 mm from the insert extension inlet & evolved to adding two 4.0 mm x 7 mm radiused slots at 3 & 9 'oclock downstream of the 45 degree bend, then evolved to 4 more 4 x 7 mm radiused slots in a radial pattern upstream from the 45 degree bend...the repetitive test/evaluate cycle evolved to all holes/slots being progressivley enlarged to 5.4 x 7 mm radiused slots which got throttle response & back pressure almost spot on except for the top 2 gears...so added 2 more 5.4 x 7 mm slots both on the bottom of the insert extension with 1 upstream & the other downstream of the 45 degree bend with all holes including the inlet wrapped in a single layer of #30 stainless mesh which functions to soften accoustic output & as a spark arrestor.
This produced the best result so far with the bike now feeling so strong in 1st & 2nd it almost feels like it could power wheelie, 3rd & 4th ride the strong mid-rpm torque curve with verve & throttle response now free reving across the entire rpm band in all gears. The newly tuned character & volume of the exhaust sound is prefered overall, in that it is muted enough, particularly at steady throttle (likely 1 to 2 db), with a slightly deeper tone that still has presence & authority under load & while blipping the throttle aggresively, along with a majority of the mid-rpm drone & raspiness I found fatiguing on longer rides tuned out, but did inch closer to the character of the muffler with just the MIVV db killer. Based on video recordings from when the muffler was new I suspect that repacking the 3 year old muffler (24k km or 15k miles) with high quality packing would be beneficial. I have no scientific proof, but the bike now feels stronger at low & particulalry at mid rpm.
A byproduct of reduction in exhaust output levels was that I now became aware of intake noise from the open design of the MWR Filtercage & Outercover that replaced the oem snorkel & airbox cover, of which until now assumed was part of the exhuast sounds. So installed a non-oiled Funnel Web Filter (FWF) main filter I had not yet used upside down on top of the MWR filtercage inside the MWR Outercover, which effectively muted out intake noises & also functions as a pre-filter. I now notice that the T7s dash instant fuel consumption display is showing lower consumption during steady & light throttle (closer to oem levels before the 2WheelDynoWorks ecu flash). I had seen a similar trend after installing the db killer insert extension, which makes me wonder if the freer flowing large opening design of the MWR Filtercage & Outercover provides more flow rate than is optimal for the T7, even with the ecu flash optimized for removal of the oem snorkel which has a smaller opening size & shape in the airbox lid (2WheelDynoWorks claim that all aftermarket airbox lids have similar airflow, but now wonder if the MWR flows enough more air that A/F ratio might not be optimal, particulalry at low rpm/low air velocity), in part, because the the bike now seems to have stronger low/mid rpm performance. The 1st full tank of fuel after completion of the db killer insert extension & installation of the FWF main filter as a pre-filter did produce slightly imporoved fuel mileage & range...but many variables are at play including cooler ambient temps, less aggresive throttle use & the mix of city vs hwy riding vs the previous few tank fulls.
I would love the Wings muffler & associated accoustic character & bling factor, but the results of this tuning project to the MIVV db killer & insert extension seem good enough to question if the expense is warranted....but does not entirely preclude it from showing up on the bike at some point in the future.😎
From the MIVV Dakar Website
MIVV Dakar Exhaust Y.064.LDKX
MIVV Dakar Exhaust Y.064.LDKB
MIVV Dakar Dyno Graph
Optional MIVV Carbon Heat Shield ACC.080.0
Optional MIVV Euro4/5 db Killer 50.DK.187.0
Optional MIVV Y.064.C1 Full Decat Header
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