YZF

[snojnke]

2019 fuel and timing settings? Benefit of aftermarket ECU?

 

[eric82930]

I met a guy the other day who got the get ecu and sent it back because it was hard starting. Seems like the stock ecu is tunable enough if you can keep the engine temps happy.

 

[M5-]

A new ecu isn't going to give you a bunch of horsepower that Yamaha forgot about on the YZ, it just isn't. The big selling point has been no fuel in your oil etc etc. That said I'm running a 2018 YZ this season and my oil changes have been clean of fuel. I always ran a Thermobob in previous years but this season I installed a C3 billet thermostat set up on the 2018. The C3 does a far better job of temperature management that the Tbob. I can't get my older YZ anywhere near as warm as I can the 2018 even adding a 190 t-stat to the Tbob. With the C3 setup I rarely even use my rad blockers. So, once you get temps under control there's not much need for a new ECU. The Yamaha power tuner app gives more control than most guys can figure out themselves over timing and fuel, its an awesome tool. I started with the hard hitting map from Yamaha but I think its a bit rich at elevation so I'm going to pull a bit of fuel and leave the timing. I know a guy with a temporary wideband setup, I just haven't had a chance to use it yet to build a proper map.

 

[snojnke]

A new ecu isn't going to give you a bunch of horsepower that Yamaha forgot about on the YZ, it just isn't. The big selling point has been no fuel in your oil etc etc. That said I'm running a 2018 YZ this season and my oil changes have been clean of fuel. I always ran a Thermobob in previous years but this season I installed a C3 billet thermostat set up on the 2018. The C3 does a far better job of temperature management that the Tbob. I can't get my older YZ anywhere near as warm as I can the 2018 even adding a 190 t-stat to the Tbob. With the C3 setup I rarely even use my rad blockers. So, once you get temps under control there's not much need for a new ECU. The Yamaha power tuner app gives more control than most guys can figure out themselves over timing and fuel, its an awesome tool. I started with the hard hitting map from Yamaha but I think its a bit rich at elevation so I'm going to pull a bit of fuel and leave the timing. I know a guy with a temporary wideband setup, I just haven't had a chance to use it yet to build a proper map.

 

[snojnke]

Thanks. I was hoping the tuner would do the trick. If anyone has any numbers they have had luck with please post them.

 

[Chadx]

Many, including me, are running all -3 across the board on fuel and +3 across the board on timing for an off trail map. Works great on my 2020. I also have a trail map that I like with all zeros on fuel and mostly -3 and -2 on timing except for some plus 2 timing up at top right corner (high rpm and high throttle opening). The thought process being a duller throttle response when slogging through slow deep moguls tames it a bit if you get thrown around and a bit more fuel may keep it a bit cooler. Most of the time I keep it on the off trail map even on the trail, but having the trail map comes in handy. 2020 bikes allow two maps loaded at once and a handlebar button to change back and forth.

 

[M5-]

The map switch is the primary difference between the 18,19 bikes and the 2020. There were some other wheel related changes that don't really apply to a snow bike. That switch probably makes the 2020 worth the price of entry over a hold over 19. My next bike will have it.

 

[needpowder]

Quite a few differences really. Probably make a lot more difference on the dirt but they changed a ton.

 

[M5-]

Yah, thanks for that, now I need a new bike...…...….honey

 

[Chadx]

Didn't watch the video, but yes, lots of changes to head and cams to make more power and lighter. Will take a look at the vid.

 

[Chadx]

Interview video kind of touched on the below, but Yamaha's website is more succinct.
Per Yamaha website:


---------------
What's new for 2020

• All-New Cylinder Head
  The YZ450F's already potent motor was treated to a host of go-fast refinements, including new combustion chamber geometry with steeper valve angles, more aggressive cam profiles, a higher compression piston with low friction rings, longer connection rod, larger exhaust head pipe connector, a high flow air filter, more efficient breather system, and more—all while fitting under a smaller and lighter magnesium valve cover.
• Smoother Shifting
  Gear widths and shapes were carefully analyzed to improve shifting feel and precision without sacrificing Yamaha's legendary reliability under racing conditions.
• Revised Bilateral Beam Frame
  The YZ450F aluminum frame features all-new flex characteristics that give riders the ultimate combination of precise cornering performance, traction, and bump stability. By tuning the rigidity balance of the chassis with changes to the lateral beams and engine cradle tube thickness as well as engine mounts, top triple clamp and front axle, the 2020 YZ450F takes rider confidence to new levels.
• New Braking Systems
  A new, more rigid front caliper and compact rear caliper work with new pads and discs to boost brake feel and controllability. The new 240mm rear brake rotor also disapates heat more efficiently, for more consistent performance under racing conditions.
• Updated Suspension Tuning
  The 2020 YZ450F features revised damping front and rear tuned in concert with the updated chassis to improve cornering performance, traction, and bump absorption. With smoother chassis movement, the rider is able to make the most of the engine's exceptional power with greater confidence.