Here are five of my favorite mods I have done to my 2023 Yamaha YZ450F in no particular order. These mods are actually mods. that I can feel on the track that makes a difference in how the 23′ YZ450F handles in west coast and east coast style conditions.
KTM/Brembo Front Brake Mod:
No surprise here that I did this to my 2023 YZ450F just like I did to my 2022. So are you tired of that spongey feeling stock Yamaha brake? Since I get to ride all the bikes, I would have to say that the Brembo system is one of the best feeling brakes out of all the MX machines. However, a little mix and matching can get you a more linear feel than an all Brembo system so we used the “Dubach Method” and combined Nissin and Brembo technology together to form the best feeling front brake I have come a-crossed in a while. If you’re looking to get a full system set up, below is the way to do it and some KTM part numbers to help you out! Most of these parts are off of a 2007 YZ450F and 2007 KTM 450 SX-F, just in case you’re searching for these on a microfiche.
Parts Needed:
Stock 2022 YZ-F brake hose (must use 2022 YZ-F caliper carrier)
KTM Master Cylinder
PN: 54813001200
Spare Brembo Lever (one comes in the master cylinder kit)
PN: 54813002100
KTM Banjo Bolt
PN: 50213025000
YAM Caliper
PN: 1C3-2580T-00-00
Spare Brake Pads
PN: 5MV-W0045-01-00
Note: The thin metal clip that goes into the carrier needs to match the older/larger brake pads. So when you take off the 250mm carrier, make sure to take the clip out and put it in the 270mm carrier.Â
WC Elite Clutch Perch/Honda Lever Ratio:
The stock Yamaha perch/lever is not bad by any means but I do like a slightly different leverage ratio and the Honda ratio has a little more linear feel to it than the stock Yamaha ratio. Enter Works Connection and their Elite Clutch Perch and black Honda lever (P/N 16-865). This combo gives the rider a better lever feel as well as a longer window for clutch engagement which helps my starts. The WC Honda lever ratio helps the Yamaha from being to “grabby” when the rider is slipping the clutch. It also helped save clutch plate life as well by a couple hours. I am a clutch dragger as I modulate my power via clutch (instead of shutting off throttle when wheelie out of corner I drag clutch to keep front end down), not throttle hand so this leverage ratio helps with this area/portion of my riding. Use the code KEEFER20 or Pulp20 if you decide to order over on worksconnection.com.
FCP Racing Engine Mounts:Â
So what is FCP’s spec? FCP uses a solid titanium 9mm front engine mount plate (instead of two split 4mm plates) and a top aluminum engine mount that has a cut out to gain some flex. Torque specs are:
 25 ft.lbs Front Mount M8
 40 ft.lbs. Front M10Â
 25 ft.lbs. Top M8
 33 ft.lbs. Top M10
So what would I want to improve on the stock chassis/engine mounts? I need more of a 22 feel on straight line where the bike feels stuck to the ground. The 23 is better on lean into corners as well as lightweight feel, but it is less stable when it comes to edge of tire comfort and off throttle harshness. So what I was looking for was to keep as much 2023 cornering capability with a little more tire contact patch/comfort. The FCP mounts gave me less harshness into braking bumps and allowed me to feel my front tire more when leaning on throttle/cutting across the track. It did make my initial lean/tip into corners a little heavier feeling but for me, but I didn’t mind that because I got so much more bump comfort, which helped me corner better. I made Chris from FCP go back and forth a couple times (stock to FCP) with me just so I could dissect every positive/negative and to me there are minimal negatives to this FCP engine mount set up. Admittedly, I am usually not a huge aftermarket engine mount type of guy because suspension spec usually comes into play and it’s hard to dial in an engine mount that works with a wide variety of suspension specs. In order to see if the FCP mounts worked with other suspension specs, I stuck these FCP mounts on a couple different flavors of suspension I had between two different bikes. The overall feeling of the FCP mounts remain the same between three different suspension specs. Better bump comfort, a calmer unload feel coming down hills, better edge of tire/on throttle traction and more stability on straight line. Again, the negative would be that it does make it a little tougher to lean into corners but I am hyper sensitive to this so some of you may not feel this. Why? Well, because you’ll be gaining so much more comfort on de-cel bumps that coming into the corners might be easier for the average rider. More comfort coming into a corner means getting through the corner is improved. I didn’t notice more/less vibration but to me, I could do without the colored look of the mounts as I am more of a stock look kinda guy. Or maybe a slightly polished look? But as long as they work, I am ok with it. For $429.00 is it worth it? Take a breath for a second… It is worth it if you feel like you need some more stability! If you like the handling of your Yamaha and have no complaints then you will not need this, but if you feel like you need a little more stabile and some bump comfort then the FCP mounts will work well for the money!
Twin Air PowerFlow Kit:Â
If you want to get rid of that plastic air filter cage system that sometimes doesn’t seal all that well on the 2023 YZ450F, go with the Twin Air Power Flow Filter Kit. To me the Twin Air YZ450F PowerFlow kit is the best all-around filter system for the YZ450F airbox. Why? With this kit, Twin Air replaces the stock air filter cage with an anodized aluminum cage, gets rid of the backfire screen for uninterrupted airflow and adds a small aluminum support bracket to hold the filter/cage in place. This ensures a more secure fit and doesn’t allow the filter/cage to float as much as the stock rubber strap piece that attaches to the filter/cage. The rubber strap is still utilized but the added security of that small bracket ensures that the filter cage doesn’t move or break the seal of the filter when accelerating. When accelerating the air volume/force that the 2023 YZ450F creates can possibly move the filter slightly and can break the filter’s seal around the lip. If you do find yourself in that situation simply get a shop vac (with a skinny end/attachment) and suck out any particles that have found its way inside the air boot. If you DO NOT open/twist your throttle after the particles have found its way inside the air boot, you will get nothing past the throttle body and you’re engine will not get any dirt inside of it. The Twin Air Power Flow Kit takes a little more patience when changing filters, but can add power to your YZ450F as well as create a better sealing surface. You can also do what I do and simply lean the bike over on a stand then take your filter off and that will prevent any dirt getting too far into the air boot itself. BOOM!Â
The Twin Air Power Flow Kit (with Power Flow filter) should be arriving to RMATVMC shortly and will cost 250 bucks! If you can’t wait, you can order right here: https://www.dominuscorp.com/amfinder/?cat=184&find=yamaha-yz-450f-2023-16848265
Akrapovic Evolution System:
The Akrapovic Evolution muffler system is one of the most beautiful looking systems out there in the market today, is well built, and has quality welds all the way around it. The change of shape in the Evolution muffler might take some getting used to but to me, it is one of the most under rated systems here in the North American market today. Great manageable power, with excellent durability makes this an expensive purchase (retail roughly around 1600.00), but holds up to the price once you’ve lived with it for a while. Once hot, the titanium color of the headpipe is the most dynamic blue you will ever see from any muffler manufacturer, which just makes you feel that much more factory on the starting line right? The Akrapovic Evolution titanium muffler system is 1.9 pounds lighter than the stock YZ450F system (stock 9.2, Akrapovic 7.3 pounds) and tucks under the right side panel fairly cleanly even with it’s new/larger muffler shape. When putting on the system, make sure to leave the headpipe loose and then connect the mid pipe, so that the slip fit joint slides in easily. Once those two pieces are connected, tighten the headpipe bolts and mid pipe bolt just snug. The Akrapovic uses your existing stock heat shields or you can purchase carbon heat shields separately. The Evolution muffler uses an aluminum spacer in the rear hole to give the muffler enough clearance (from the brake caliper) once the suspension is fully collapsed. This system is one of the easiest to install and I have been putting a ton of systems on this blue bike lately. I did notice that there is a small screen deep inside the core of the muffler, however I was told that this isn’t a spark arrestor, but a noise insert. Note: Leave this screen/insert in, as the muffler performs better with insert in and is much pleasant to the ear. Once rear section (muffler) was installed, I went around and tightened up the remaining bolts. Doing it this way ensures there is absolutely no binding going on between each slip fit joint.
Out on the track the Akrapovic Evolution muffler. felt similar to the system I had on my 2022 YZ450F. It has a deeper sound and is much quieter than the stock system. I started the test with the Controlled Torque and stock maps installed inside the 2023 YZ450F (if you don’t know what the Controlled Torque map is, email me at kris@keeferinctesting.com). Roll on power delivery was smoother than stock out of corners (with either map) with the Akrapovic, compared to the stock system. I have grown to love the smoother roll on power that the Evolution system delivers as it really helps me roll my corners better without getting the chassis upset. Even the the 2023 engine character is slightly smoother down low than the 22, the Akrapovic muffler feels more connected to the rear wheel so that little extra smoothness this muffler provides helps me “control” the bike more. The connectivity of the Akrapovic muffler is second to none as you will notice more rear wheel connection under heavy throttle without breaking the rear end loose as much.Â
The Akrapovic system really comes to life once out of corners as the Yamaha now starts pulling harder and longer than the stock system down straights. Second and third gears can be stretched longer by the rider with the Evolution system and rolling third gear in corners is slightly easier on the rider as well (with stock gearing). Over-rev is better through each gear with the Akrapovic and the overall engine feels like it revs a little quicker/freer yet has more rear wheel traction. The freer feel takes away some engine braking sensation on de-cel and also helps the Yamaha handle slightly better coming into corners. Yes! All from a muffler!
In conclusion, I feel the Akrapovic Evolution muffler system is an excellent system once you can dial in your favorite desired Yamaha Power Tuner App setting. You will not be getting more low end RPM response than a stock system, but the gains through the mid-top end are a noticeable difference and who needs more response from this bike anyway? Not me! It will be up to you if that difference is worth the $1600.00 price tag that the Evolution titanium system comes with. However, in this case, you get what you pay for! Akrapovic’s website is a very informative, clean, and one of the best aftermarket muffler websites to browse around on if you have the time. There are dyno charts, a sound tool that lets you compare the stock system to Akrapovic’s muffler pitch, documents of replaceable parts, and technical data about the system itself. You can head over to akrapovic.com and punch in what bike you want to geek out on. I did, for a while!
(Alternative) FMF 4.1 Slip On:
It’s like the FMF 4.1 slip on system fills in the gap between the bottom to mid range. Compared to the stock power, the FMF 4.1 muffler gives you a smoother low end power with more of a liner feel and kills the mid range hit a little where it can be easier to control coming out of corners. You might be saying to yourself, “it sounds like the FMF 4.1 muffler makes the 2023 YZ450F slower”, but that is not technically correct. It shifts the power in areas that makes the Yamaha more rideable for us mere mortals that purchased this fire breathing machine. Second gear roll on is more manageable to my throttle hand and the 4.1 system does have more connectivity to the rear wheel than the stock muffler and revs out just as far with more of friendlier pull into third gear. Connectivity is important and getting a muffler to give your YZ450F more rear wheel traction is important. Picture you massaging the throttle as you exit a rough corner. When you do this you want your engine character smooth so the rear wheel doesn’t spin as much and can drive through the bumps instead spinning on top of each of them. This FMF 4.1 allows the rider to be more aggressive with the throttle yet gain more traction that of the stock system! You will not be getting more lugability with the 4.1 muffler but going up to a 50 tooth rear sprocket can help you run third gear more in corners with this FMF 4.1 set up. You also will be losing a little over one pound with this system so for you guys that are counting calories, you can rejoice on the diet you just purchased. Also, I liked the 4.1 slip on with the insert IN as it was smoother and (to me) sounded better to the ear. For around 800.00 bucks this is a system that can help make the YZ450F more rideable as well as look better! Go to fmfracing.com to get yours, because they usually go quick!Â
Quick Hits:Â
Hinson Inner Hub And Pressure Plate With Fibers/Steels: The 2023 clutch on the Yamaha YZ450F doesn’t last very long and installing this Hinson Inner Hub and Presure Plate extends the life of your plates. I currently go back and forth between Hinson fibers/steels and OEM but regardless the Hinson Inner Hub and Pressure Plate extend the life of your 23 YZ450F’s clutch.
GUTS Racing Seat Foam: The Yamaha seat foam sucks ass! Literally! It hurts your butt and gives you the gnarliest monkey butt ever! The GUTS medium foam helps with this but we do need a different seat shape to help with the dreaded butt soreness!Â
Dunlop MX34 Tires: Get rid of those MX33s on your 2023 YZ450F and get a set of the latest MX34 tires. Run 13PSI in the front and 12.5PSI in the rear. Thank me later.Â
As always, I am here to try and help when I can. Email me at kris@keeferinctesting.com if you need some help.
