ASK THE MXPERTS: DOES MXA HAVE ANY UPDATED 2023 YZ450F MAP DATA?

Dear MXA,

I am the proud owner of a new 2023 Yamaha YZ450F, so I read the YZ450F test in the March 2023 issue very thoroughly. Several things caught my attention in the MXA test that I could feel on the track.

First, you said, “At the first twist of the throttle, the YZ450F is ultra-responsive. It isn’t herky-jerky down low like last year’s YZ450F engine; instead, it is overly sensitive to the slightest rotation of the throttle tube.” Boy, is that ever true. I found myself wheelying when landing from jumps or turning the throttle on when exiting ruts. I noted that you said, “We tried Yamaha’s optional “Smooth Linear” map (blue map button lit up) in hopes of taking the bark out of the low-end.” You said that it didn’t help. I concur. I downloaded that map, but it still had that aggressive bark right off idle.

So, what I really want to know is, what have you done since writing the YZ450F test that I can use to calm my YZ450F down—a lot?

In the time since we wrote the YZ450F test, we have put a lot of hours on the YZ450F with different test riders on a weekly basis. The first thing we did was to raise the gearing by going from the stock 49-tooth sprocket to a 48. This made second gear taller, which cut down on the amount of thrust it generated out of corners and allowed it to pull further before we had to engage third gear. It helped, but it wasn’t a cure all for the overly snappy throttle response.

The second thing we did was to get the Yamaha R&D department to give us an even mellower map than the “Smooth Linear” map we started with. We tested the new map for a week and then told the R&D guys that we needed it to be even more detuned down low. To their credit, the R&D guys suggested a map with even more fuel between 2000 and 5000 rpm. The added fuel took away some of the crispness and toned down the bark.

Here are the the fuel and ignition map charts that we have been running on our 2023 YZ450F.