YZ400F Exhaust by Up Tite Racing
by Jeff Bell

There are a lot of pipe manufacturers making outrageous claims with regard to their solution to the YZ400F, however only one stands up to its’ sales pitch. The Up-Tite Racing system not only offers the most horsepower and torque increase, it doesn’t sacrifice any part of the powerband while doing it.

Rear View of Installation

I caught wind of the Up-Tite Racing pipe from a friend of mine in Bishop, CA. When he found out that I had purchased a YZ400F he told me I should contact Up-Tite about their pipe. He said it was the best-kept secret among YZ400F owners. He went on to tell me that some resident pros were using the pipe and were amazed at the difference it made.

I was still skeptical. I am a 41 year old Intermediate and I was very happy with the power delivery of the stock system. I have also never really believed any of that hype from pipe manufacturers, most dyno tests I have seen prove the stock systems to be the best. I too have purchased pipes and really could not tell any tremendous improvement.

Still, I was curious. I saw more and more pipes become available; and the FMF, Yoshimura, and White Brothers lead the polls. Also these systems had healthy price tags; header and silencer totaling around $600.00!

I recently was in Santa Ana, CA, the home of Up-Tite Husqvarna (a.k.a. Up-Tite Racing). I decided to call the owner, George Erl and see if I could talk to him about their product for the YZ400F. George showed it to me and told me all about the pipe. It was the section from the header back. I asked about the header pipe. He told me that there was no gain from changing the header. This system utilizes the stock header. Wow, that’s a cost savings of approximately $300.00!

He told me that he was spot-on with the design because he had been building the pipes for the Husqvarnas for years; remember he is a Husky dealer. He told me that the bore and stroke for the Husky 410 was within 0.5 mm of the bore and stroke of the YZ400F. He simply applied what he knew worked for the Husky and made the geometric changes appropriate for the YZ frame.

He went on to tell me about the article written in Dirt Bike magazine and the dyno results his pipe produced, an honest 49 HP! It smoked the competition. However due to "unknown" reasons Dirt Bike gave the better press to pipe manufacturers who just so happen to advertise heavily in their publication. Hmmm.. coincidence?

He also told me that if I really wanted, he could get me 5 more horsepower with a slight modification to the pipe.

I was convinced enough to make the meager ($289.00 retail vs. approximately $600.00 for the competitors hot set-up) investment. I took it home and mounted it up.

George asked me if I wanted the "Go Fast Stinger" or the "Slow Me Down Stinger" for the end of the megaphone. The Go Fast Stinger has an approximately 2" ID and the Slow me Down Stinger has an approximately 1.5" ID. I asked what the difference was. He told me that the Go Fast Stinger was the one to use for maximum power delivery performance. The Slow me Down Stinge" should be used on slick track conditions for better rear wheel control. The pipe can also be tuned utilizing Supertrapp discs.

I elected the Go Fast Stinger.

The fit was very good. I had to tweak the rearward bracket about 10 degrees inward to match the correct angle of the sub-frame-mounting boss. George had instructed me to use the red high temperature silicone around the I.D. of the pipe where it slides over the header.

I also discovered that due to the size of the megaphone section I had to unbolt the rear brake reservoir during installation.

The pipe looks awesome! Once installed I kicked the Yamaha over. What a sound! Hollow, mellow, robust, testosterone pumping, etc….

I took it to the track the next day. A friend met me there who also happens to ride a 1998 YZ400F, only he has the trick setup from White Brothers. He is a 21-year-old pro-level rider.

I took some hot laps first to get used to the bike. I was amazed at the noticeable difference in the mid-range and the over-rev. Unbelievable!

I came in and traded bikes with my buddy for an A-B comparison. His bike felt like a trail bike compared to mine. I noticed immediately that the Up-Tite pipe pulled harder of the bottom as well as the mid and top. I was totally convinced at this point but wanted to see what my friend had to say of my bike.

He described it as violent! He said there is no comparison between the Up-Tite Racing system and the White Brothers setup. The Up-Tite pipe won our impromptu test hands down. He said that he definitely wanted to switch to the Up-Tite unit.

I guess George lived up to his promise. "He builds horsepower- period!"

For more information:

Up-Tite Racing
Santa Ana, CA 714/540-2920


tyler (not verified) said:

if the pipe adds that much hp then wouldnt the gas use drasticaly go up?

Anonymous (not verified) said:

Yup. No more putt putt putt. More like BRAAAP!!!!

Anonymous (not verified) said:

were can i get one ?<br />and at what cost ?

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