Suspension Testing With Mark Johnson

Suspension Testing With Mark Johnson

Since we started Motion Instruments, we’ve had an opportunity to work with the best MTB and Moto racers in the world. What you may not realize is that there is a team of professionals working in the background to support these riders on many aspects of their career and training.
Since we started Motion Instruments, we’ve had an opportunity to work with the best MTB and Moto racers in the world. What you may not realize is that there is a team of professionals working in the background to support these riders on many aspects of their career and training. Racing is an intense way to make a living and often these riders are pushing the limits of their machine and body. With respect to motocross, suspension is a key area that riders want to focus their training and testing. One of the leading suspension tuners in the business is Mark Johnson, founder of REP suspension (@researchengineeringperformance). Mark has worked with the best riders and teams in the business and has recently incorporated data from Motion Instruments into his product offering.

We have been working with Mark for a few months and what struck us right away with him is his extraordinary detail into the dynamics of a motorcycle as a system. Mark uses cutting edge software to quantify the entire bike. He will model every part of a suspension, swingarm, frame, and geometry of a bike as part of his analysis. He uses this model to understand the dynamic forces on the suspension. He’s even designed his own linkage to modify leverage ratios to help the rider. Mark then does a lot of testing at the track and is constantly feeding back what he learns into his custom tuned suspension. We asked Mark a few questions about his career path and what eventually led him to work with us.

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Beta tests with data going smoothly

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1. How did you get involved in motorcycles, racing, and eventually suspension as a career?

I grew up racing, but was never fast enough to make it a career, so I decided I needed to find a way to turn my passion for racing into something that I could make a living off of in the long run. What sparked my interest in suspension is that it is never ending and is never perfect. There is an endless goal to try and achieve the perfect setup. I have learned new information daily in my 17 years of suspension and the more you discover the more evident that there is so much left to uncover. Suspension is the limiting factor on how a motorcycle can be ridden to its full potential; you can build a fast motor, but the bike can only be ridden as fast as the suspension allows. I believe suspension is the key to finding true progression in the sport.

2. How did you learn about suspension?

I attended Cal Poly Pomona for mechanical engineering with the goal to obtain a deep understanding of dynamics and fluids. My end goal was to apply what I was learning in school to motorcycle chassis and suspension. While at school, I was working at a performance motorcycle shop and trying to develop setups on my personal bike. It was completely trial and error for me in the early stages. I had no real idea what I was doing with my suspension for the first few years. From there, I offered to do suspension for anyone that would let me quicken the learning curve of grasping basic concepts of how suspension is reacting to change.

3. When did you get into motocross/supercross as a suspension tech? What riders did you work with?

To break into the industry, I knew no one, so I attended all of the local professional events and handed out my resume for two years before I finally got the call from KTM at the end of 2009. With Roger Decoster leading the team, it was the level of professionalism I was looking for. I had the pleasure working with many great riders, but some of the notable riders that come to mind at KTM are Ryan Dungey, Marvin Musquin, Ken Roczen, Taddy Blazusiak, Cooper Webb, Kurt Caselli, Dean Wilson, Jeffery Herlings, and Kailub Russell. Notable riders for my suspension business, Research Engineering Performance (REP), are Chad Reed, Brock Tickle, Ryan Sipes, Jacob Hayes, and Jared McNeil.


4. Tell us about your testing process? How did you incorporate feedback into changes?

Testing for me is still educated guesses in a sense, just because ideas that look good on paper does not mean it will resonate with the rider. The only true answer is found on the track, Every rider is looking for something different and their styles manipulate and load the bike in such a wide variety of ways, all ideas must be track tested. Your eyes are one of the most valuable assets you have in making improvements, but with eyes comes human error. This is where our real tools come into play. Once you have seen for yourself how the bike is reacting and collected rider comments, it is now time to look at the data. The beauty of data is how quickly it cuts time and guess work. After data analysis, I like to combine what I saw on the track and what the recording shows to make a decision on changes that are needed to be made. After all there is an infinite number of ways to make corrections, but the goal is to find gains with the least amount of negative side effects. For this reason I feel changes can not be made purely off sight and need to be directed by data. Once the test day is concluded, it is back to the drawing board, all settings and data will be put on a dyno simulator to further study and link everything together.

5. Did you ever use data in your testing on the track? What were the challenges?

I have previously used a system developed by LitPro, for all laps allowable by the AMA. The challenge I faced with this, and similar systems is that I do not have the confidence to work with all the setup of the electronics and recording devices. This is ultimately why I had immediate interest in the Motion Instruments setup, as it was plug and play. I no longer needed to take the seat off and figure out how to get everything connected and operational. Most systems are not straight forward, where Motion Instruments is very user-friendly and can bolt up to a bike the day that the system is received in the mail. Another issue I have had in the past is having a single license on one data laptop that needed to attend every test and race. What Motion Instruments has done has given us access to data anywhere we may be with our "laptops" in our pocket.



6. How has your testing changed with MI? What was the biggest impact?

We now use data for all of our testing and it is a staple of our platform.The system can be quickly set up on any bike and implemented into anyone's program. I can test with KTM on Monday and get a call to have a Honda test the next day and it is no stress to do so. It now offers our customers rental programs, which has been great. It not only has sparked people interested in using us to set up their bikes, but gives the business another source of income. Even though the rental program has already been beneficial, the main impact is improving our baseline settings. The system is now a key factor in our development and not just a means of another source of profitability. I can honestly say that we have completely changed our baseline setting for all bikes. Customers that were already happy before the assistance of the system improved our baselines, are now ecstatic at the improvements.

7. How have the riders responded to the changes? What was the biggest change you did to a bike and what was the rider feedback?

It is a confidence booster for the riders to not only see how quickly improvements can be made with the system, but also how black and white the data shows information. For us, we thought we had a solid setup for all current bikes, especially the Austrian brands. Quickly we learned how far off we really were. Even our most successful setup proved to be very far off once we saw where we were at with the data. Our fork was clearly stiff and our shock rebound was far too slow. Once we corrected this on our test bike, we began applying this to our customer base. Customers were blown away in the fact that they thought their setups could not be improved and once the changes were applied it was obvious there is still much room for growth. It has opened our minds to think outside the box and try directions we have never thought to venture.



8. Has your business expanded since offering data as a service?

It has opened up new sources of income for us. We now offer three levels of support that we could not do without the system.
We no longer lose efficiency at the shop and can still support our riders. We offer riders rental of the system and have us remotely analyze the data. The benefit for me is I can still run operations at REP while offering real time suggestions to our customers at the track.
We have always offered hired test days, but customers now have the option of our "factory for a day" test days that includes data for the day at a higher daily rate.
We have riders remotely around the world who can send us information in an instant. This not only saves us the time and expense of traveling, but also gives us a new revenue stream. It’s a win-win. The customer gets better service at a reduced cost. Also, testing is constant and not limited to facetime at the track.

9. What are your plans for the future employing data with your customers?

The options are endless and I feel we are just starting to find the many benefits of giving our customers access to factory level data as a service. We will keep building our program with the system and I am sure we will find more avenues other than that previously listed.


That was a pretty in-depth look at Mark’s career and business. It has been great to work with Mark and he’s had a lot of great feedback to help us improve our product. If you are looking for an expert to help you tune your bike, hit him up.

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