JT Sprockets JTF 1591 - 16RB 16 Tooth Rubber Cushioned Front Sprocket provides 6.3% higher gearing from the oem 15/46 = 3.067 gear ratio to 16/46 = 2.875% gear ratio (MT-07 uses 16/43 = 2.688 overall ratio), which reduces rpm by approximately 283 rpm @ 100kph in 6th gear according to this gearing calculator. Many other T7 owners have made the change, mostly to improve highway droning & mileage, with little penalty for most off-road riding except technical & steep terrain....easily switched back to the oem 15 tooth when needed, or for those harder core, super sized dual sport fans some have opted for a 14/46 = 3.286 gear ratio. The slightly taller gearing will be welcome, particularly in city stop-n-go riding where I currently start in 2nd most of the time because of the low 1st gear & strong, linear low down torque that can see you short shifting to 3rd gear before you have crossed the intersection + stretch out each gear slightly for more relaxed riding.
Once the fitment issue noted below was resolved, a 30 mm impact socket obtained (see post below) & the oem front countershaft sprocket nut loosened (use of an impact gun with the transmission in neutral & the rear brake fully on made removal of the countershaft nut easy), installation was relatively easy, but will require chain slack to be reset (see post below). The oem 122 link chain length & 25 mm of adjustment range accommodated the 1 tooth larger sprocket & should allow 1 tooth smaller than oem at the front, but not sure how many teeth difference if can accommodate at the rear before requiring additional links. The service manual recommends a new nut (#90179-22018) & conical spring washer (#90208-22002), although some will reuse them if in good condition & within spec tolerances..
Initial Ride Review May 06, 2022
The 6.3% taller gearing change (2.875 vs oem 3.067) seems a very good fit for the T7 & my mostly 70/30 road/dirt biased, solo, minimal technical terrain riding with the lower gears, in particular, now being more usable & stretched out giving the bike a more relaxed demeanor, resulting in smoother throttle response (the Camel ADV 1 finger clutch mod produces lighter lever pull & a wider engagement point that also improves shifting smoothness). 1st gear is now more usable in the city while the ample low down torque, linear powerband & good fueling of the CP2 motor still easily starts in 2nd gear without increased susceptibility to stalling & idles effortlessly in 1st at an indicated 12 kph & in 2nd at 15 kph (my T7 speedo reads about 8-9 kph higher than my gps at 100 kph). 3rd, 4th & 5th become more usable across the board & still provide ample roll on acceleration from 2-3k rpm depending on gear, while 6th now feels more like a hwy gear but still pulls without bucking from as low as 70 kph.
This gearing, imho, better compliments the T7 CP2 powerband for average pavement/adventure/FSR non-technical use than the 3.067 oem gearing, which tends to encourages short shifting in everyday riding. An ancillary benefit should be improved fuel mileage/range. Overall, I really prefer the feel of the bike now & have not noticed any increased vibration/resonance that a few others have cited (perhaps because I'm using the rubber cushioned version similar to the oem front sprocket)...but can easily revert to oem & shorter gearing if desired.
Aug 2022 Updated Ride Review after 10 day 3,800 km Trip Including 20% Off-Road
This trip just reinforced my preference for this gearing over the oem for all but perhaps steep technical riding & even then with a little clutch proficiency it would be a rare occurrence that you would miss the 15 tooth or need to worry about any increased propensity to stall. The 16/46 ratio is still lower overall gearing than most of the T7s competition keeping lower gear low rpm speeds in check for most technical & steep terrain. I saw 18% grades on this trip & never felt like the gearing could not control my speed or I needed a lower gear.
The amazingly linear & torquey CP2 motor still handles 2nd gear starts with ease & 3rd with some clutch feathering, pulls smoothly from between 2 & 3k rpm in any gear & chugs up dirt grades in a higher gear at lower rpm than many other mid-sized ADV bikes, aiding traction & confidence. It eats up hwy miles in the 100-130 kph (62-81mph) range more relaxed & still has plenty of reserve to roll on past slower traffic beyond 160 kph (99 mph) without dancing on the shifter....I had no problem keeping up with my friend's KTM 990. The slightly stretched out nature of the gears with the 16 tooth makes for smoother & fun surfing of the mid rpm torque, particularly in twisty, hilly terrain. I just prefer the T's overall demeanor better!
JT Sprockets Gearing Chart (Note: uses 15/45 vs 15/46 as the reference ratio)
Finer tuning of gearing can be obtained via rear sprocket substitution, whereby 1 tooth at the front = ~3 teeth at the rear....see gearing chart below. A 2 tooth drop at the rear to 15/44 teeth = 2.933 overall gearing or a 4.4% drop from the oem 3.067 which will drop rpm by approximately 197 rpm @ 100kph in 6th gear as per the above mentioned gearing calculator.
Fitment Issue
Update Jan 2022: This particular sprocket purchased from FortNine, despite confirming with JT Sprockets Catalogue that it is the correct part # for the Tenere 700 & MT-07, will not fit on my Canadian T7 oem output shaft with only 7k km (the oem easily slides on regardless of which way it is rotated)..it is a very snug initial fit once the splines are aligned & must be rocked back & forth but stalls out only 3-4 mm onto the shaft with just the sprocket (no chain)...I emailed with Richard @ JT Sprockets & sent pics, but have not had any further response. I'm speculating a quality control issue with manufacturing tolerances of the sprocket spline side surfaces...see pics below that show the friction point on the output shaft. Most have reported no such issue with their JT sprockets, but a few others have recently. Another observation is that the JT sprocket teeth are thinner at the top. FortNine refunded my money & told me to keep the sprocket. The oem sprocket nut required an impact gun to break it loose. After some very light dremel work on the splines it now fits like the oem.
The JT Sprocket JTF1591-16RB will fit onto the oem output shaft splines only about 3-4 mm
The friction point can be seen on the 1st 3-4 mm of the output shaft spline sides
Yamaha oem 15 tooth sprockets slides easily on output shaft regardless of which way rotated
JT Sprockets JTF1591-16RB on left vs oem 15 tooth on right, note difference in thickness of the top of the sprocket teeth.
JTF1591-16RB placed on top of oem 15 tooth sprocket
OEM 15 tooth sprocket on top of JTF1591-16RB
Update Feb 2022: It now fits on easily like the oem 15 tooth after some very light dremel work on the splines 😀
Chain Adjustment Procedure & Establishing Baselines Including Tightest Point of Wheel Travel
Adjust chain slack (7k kms on oem chain) as per service manual (see pic below), (43 - 48 mm adjustment range with a slack limit of 55mm), which required loosening the optional oem rear chain guide to allow for full chain sag (it restricts chain movement by approx 2 mm)...then went on to establish baselines for future adjustments by placing the swingarm inline with the drive sprocket, swingarm pivot & axle which produces the tightest chain tension that resulted in a 5 mm tighter measurement than with the bike on the side or center stand & the wheel fully extended (there appears to be no difference in measurements when using the side or center stand).
The Owners Manual specifies: 1) Place the motorcycle on the side stand; 2) Shift the transmission into the neutral position; 3) Push down on the drive chain under the end of the drive chain guard; 4) Measure distance between the drive chain guard & the center of the chain. I set slack at 43 mm w/rear chain guard fully installed, which equates to approx 45 mm without the chain guard which resulted in 40 mm at the tightest arc of the swingarm. This produced chain range of movement up/dn of 29 mm or 1 5/32" from lowest to highest range of motion. I then measured each side from the axle to the swing arm pivot to confirm alignment...the alignment marks on the adjuster blocks are reasonably accurate for establishing rear wheel alignment.
CASOMAN 1/2" Drive x 30 mm Deep 6 PT Impact CR-MO Socket
Manufactured from premium impact grade chrome molybdenum steel construction with corrosion-resistant black phosphate finish for durability.
High-torque, 6-point opening grips flat sides of fasteners, not corners, preventing round-off
Engineered for use with impact drivers, This axle nut socket can be used for the removal or installation of axle nuts.
Large, high-contrast size marking is permanently laser etched and easy to read, even in low light
Meets or exceeds ANSI performance standards. It comes with 1 year quality warranty.
Outlaw Racing Products OR3074BK Chain Roller Guide have sealed bearings & are quieter than the oem units, which are noisy, BUT with not as durable rubber.
Yamaha Chain Guide BW3-F21G0-00
D.I.D. 525VX3 130 Link Chain
The oem chain (2021 Canadian model - Japan Factory) is a DID V11 525 & is already starting to have sticky links @ 7k km of light duty use, very little off-road & proper maintenance so ordered a D.I.D X link chain for when it needs replacement.
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. De...
8 Day, 4,360 km (2,709 mile), 'Rideabout' - 2 Provinces, 5 States, 1 Provincial & 4 National Parks - Aug 7-14, 2024 With each year, & officially a 'baby' senior at 66, motivation & ability to do the things I historically treasured become a plethora of balancing the increasingly disparate physical & emotional realities with the seductive biased recollections of my youth touring much of western Canada & USA, Baja/Central/Northern Mexico & 2 years in Texas via motorcycle...Bob Seger's "Against the Wind' echoes in my head 😎. After having to cancel my Yukon/Alaska trip this June because of recurring back issues, & while no where near 100%, was in need of some throttle therapy & seized an opportunity. The ensuing journey is as much an exploration of my current abilities for a concentrated high mileage solo 1 or 2 week long 'rideabout' without much conditioning & lead up riding as it is about my accessorized ...
Disclaimer: I am just a long time motorcycle enthusiast with moderate wrenching experience/skills (not a professional/Yamaha mechanic) & have compiled this info from others more experienced & knowledgeable as a reference based on my personal experience with my T7 that hopefully can help others. Fork Alignment & Right Fork Caliper/Rotor Position MUST Be Checked After Front Wheel Removal! T he T7 right front axle assembly is a floating design that, depending on several factors, may not correctly position the caliper & rotor for equal gap & can result in the rotor resting against the upper edge of the caliper...not a desirable situation if gone unnoticed. This information is NOT in the Yamaha Service Manual & can be an overlooked issue when changing the T7 front tire .. .the right fork's static/resting position is toward the outside on my T7, which incorrectly positions the inside edge of the caliper to make contact with the rotor ( has been posted by others ...
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