If there is one area that the 2018-2019 Yamaha YZ250F/450F is lacking in, it would have to be the seat foam/seat cover area. Yamaha firmed up the seat foam for 2019, but to me it just wasn't enough for my skinny ass. If you have a Kardashian butt it might be ok, but for us skinnier riders we need a foam that doesn't sink into the fuel tank when slamming into corners. While I was searching for a firmer foam, I thought why not get a seat cover that has some ribs on it, in order to keep my but in place when coming out of corners as well!
So I called up Andy over at GUTS Racing and he sent me their standard firm foam (not Phantom foam) and GR1 ribbed seat cover with extra padding sewn into the sides of the seat cover. Guts offers many different styles of covers and foam densities so make sure to check out gutsracing.com for all of their offerings. Swapping out seat foam isn’t that hard, it just takes patience and some trial and error to get the new cover on the seat. The foam shape is pretty much identical to the stock foam and went on the seat base without issue. The seat cover went on without much of a fuss either, but there might be a little extra material that you may have to trim once all of the staples are in.
So when you think of the words “hard” or “firm” you may think of uncomfortable right? Well in this case you would be wrong. The “firm” GUTS foam is just what the doctor ordered, especially when I am slamming into corners. The stock 2019 YZ450F foam is a little better (than the 2018 foam), but lacks density on the sides where my butt is forcing the foam down. With the GUTS firm foam the density is harder in the middle of the foam, but also on the sides of the foam where you need it (especially when riding aggressively). Your butt is not always placed directly in the middle of the seat when you're riding, so why just make the middle part of the foam firm? GUTS thought of this because all of us riders need to have a firm feel on each side of the foam as well. The GUTS Racing foam provides the correct amount of density so I am not pushing my tushy through the foam and into the plastic of the fuel cell. My butt bone thanks you GUTS Racing!
The GR1 GUTS Ribbed Seat Cover is unique because of the extra padding that is sewn into the cover on each side. Since the Yamaha seat is designed so thin near the middle portion and on the sides, I felt like I could use a little extra padding when working the sides of the seat through flat corners. Not only did I feel like the extra foam on the sides helped me through flat corners with the slightly wider nature of the seat cover (due to the foam inserts), but it helped me grip the Yamaha better with my legs. Not to go full Ryno on you, but using your legs is crucial to going fast on a motorcycle. Gripping the machine with your legs is sometimes overlooked to an amateur rider, so with these extra foam inserts inputted into the seat cover, it really helps me grip the side of the Yamaha when I am getting tired. It may not be the most attractive looking cover (due to its width), but it sure does do what its supposed to do. The ribbed portion of the seat cover also keeps me in place, but the gripper material isn't so gnarly that it is chaffing my ass on long test days. Some gripper materials out there are so aggressive that you can only ride one full day on it before you have to have your wife rub chamois cream on your ass.
If you own 2018-2019 Yamaha YZ250F/450F do yourself a favor and get a GUTS Racing firm seat foam and ribbed GR1 cover. Your ass can thank me later. The GUTS Racing standard height/firm seat foam will run you $89.90 and the ribbed GR1 seat cover with foam inserts on each side will cost you $149.90.