FMF - Keefer, Inc. Tested

FMF 4.1 Full System Vs. Akrapovic Evolution Full System Vs. Akrapovic Slip On

We recently received the 2020.5 KTM 450 SX-F Factory Edition and after dissecting it for a few weeks, we thought we would test a couple different muffler systems on it. We wanted to see if we could improve upon the KTM Factory Edition’s delivery. The KTM comes with an Akrapovic slip on we thought since…

ByKris KeeferMarch 16, 20200Comments

Bike Brands Bolt-Ons Exhaust KiT Performance Yamaha

Yamaha YZ125 Pipe/Silencer Comparison (Pro Circuit Vs. FMF)

For over 10 years the YZ125 engine has remained the same. At one time it was the best 125cc engine around, but in recent years that award has gone to KTM/Husqvarna. KTM and Husqvarna’s latest 125cc engines have a wider powerband and is simply more exciting everywhere on the track. Compared to the KTM and…

ByKris KeeferJanuary 30, 20200Comments

Bike Brands Kawasaki KiT Motocross

2020 Kawasaki KX250 Top 5 Mods

Kawasaki did a great job for 2020 on improving the KX250’s overall engine character as well as getting a much better suspension spec. Kawasaki made changes to the engine, went to a bigger throttle body, switched to KYB suspension, updated the brakes, changed the low front engine mounts, and shortened the headpipe by 30mm for…

ByKris KeeferJanuary 7, 20200Comments

Bike Brands Bolt-Ons Exhaust KiT Performance Yamaha

FMF 4.1 RCT Stainless Muffler System For 2020 YZ250F

Written/Tested By: Michael Allen It’s no secret that the YZ250F is one of, if not the best 250F in the class for 2020. One of the things that makes the YZ stand out is the raw amount of torque it produces compared to the other bikes in the class. Some of the other bikes may…

ByMichael AllenDecember 16, 20190Comments

Bike Brands Bolt-Ons Exhaust KiT Performance Yamaha

FMF Vs. Pro Circuit (2020 Yamaha YZ450F Muffler Comparison)

Yamaha did a great job with the stock muffler and I bet if you ask any aftermarket muffler manufacturer they would tell you the same thing. If you’ve seen my social media pictures while riding the Yamaha YZ450F, you will see that I run the stock system quite a bit. Why? Because it’s really good!…

ByKris KeeferNovember 25, 20190Comments

Bike Brands KiT KTM Motocross

2020 KTM 450 SX-F World Vet Race Build Parts List

I raced the Keefer Inc. 2020 KTM 450 SX-F test bike on day two of the World Vet’s and I wanted to put together a parts list of everything that was on my bike. All of the parts on this list were either agreed upon or hand picked by myself because I knew they worked…

ByKris KeeferNovember 6, 20190Comments

Bike Brands Bolt-Ons Exhaust KiT KTM Performance

FMF Factory Fatty Pipe/Shorty Silencer (2020 KTM 125SX)

Since the delivery of our KTM 125 SX, my son Aden has been riding it non stop. He also has been barking in my ear about getting a pipe and silencer so it “sounds cool”. While I am usually reluctant to add parts to my kid’s bike for the sake of just doing it, I…

ByKris KeeferOctober 23, 20190Comments

Bike Brands Bolt-Ons Exhaust Kawasaki KiT Performance

FMF 4.1 RCT Muffler With SX Style Megabomb Headpipe (2020 KX450)

The Kawasaki KX450 was the most improved 450 machine of 2019 and with Kawasaki not changing anything on the 2020 KX450, I wanted to test some new aftermarket parts to see if I could improve on what I already knew from last year’s machine. I knew FMF had two headpipes available for the KX450, but…

ByKris KeeferAugust 28, 20190Comments

Bike Brands Bolt-Ons Exhaust KiT Performance Yamaha

FMF Factory 4.1 Slip-On (2019 Yamaha YZ450FX)

Story By: Michael Allen The simple fact that more manufacturers are offering off-road closed course competition bike’s brings a smile to my face since at heart I’m an off-road lover. That being said I feel like most manufacturers should know that 99% of all off-road racing organizations require race bikes to be equipped with a…

ByMichael AllenFebruary 14, 20190Comments

Bike Brands Bolt-Ons Exhaust Kawasaki KiT Performance

FMF 4.1 RCT Titanium Muffler System (2019 Kawasaki KX450)

The 2019 Kawasaki KX450 is the most improved machine of the new year, hands down! It has a very responsive engine character, comfortable suspension, a lightweight feel and cornering that is very neutral. I will be the first one to admit that I get nervous about sticking on any type of aftermarket muffler system when…

ByKris KeeferAugust 14, 20180Comments

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