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RM 125 Resurrection

It’s the race bike that… kind of was? What started as a “wouldn’t it be cool if” idea between Pro motocross racer Ben Robinson and myself soon started to become reality. Find a cheap 2005 or newer RM125 and make a race bike for the 125 All Star class. I love woods riding myself, so I figured this can also double as a J Day machine. The exact order is a bit foggy now but I reached out to Kurt at Trail Rider and Beau Viens to ask about getting this bike build in the magazine and maybe having the test ride at a J Day race or two.

Everyone was very excited about the idea and just like that I was off! Scouring the depths of Craigslist, Ebay and Facebook Market Place for a good deal on a 125. A 2005 RM125 that needs some work popped up within 20 minutes of my house. After a quick pit stop at the ATM on the way home from work the next day it was mine. Lets just say I had my work cut out for me.

The bike was mostly together but it didn’t run and it certainly needed some TLC. The first step was pull the motor out and figure out what was going on. After a little digging I found out that top dead center was about 10mm lower than what it was supposed to be. What I figured had happened and what I later confirmed is that the previous owner had accidentally gotten the wrong crank, which means the stroke was wrong. Easy enough, the motor and all of its parts were put in a box and set on a shelf for later.

The next task was to tackle the chassis and make a list of what is needed. The list seemed endless and the project fought me every step of the way. Nuts had to be tack welded onto what used to be Allen head bolts holding the rear brake master cylinder on! After a few hours and a few creative sentences made up of some choice words, the bike was just a frame ready to be sandblasted.

This is where the project stopped for a while. I had to leave for Minnesota for work for the winter. While I was gone I was able to reach out to some of my old sponsors and build relationships with a few new ones to get some help building this project. The title sponsors was STEEL-IT Coatings. They produce a coating that has actual stainless steel in it so that the coated part can be welded without the need to strip the coating. Then you spray a little more over the welded area and it’s like it never happened. STEEL-IT gray is what the frame was going to be coated in and the swingarm, subframe and engine cases were getting black. Not that I planned on welding on the frame but the coating is tough as nails and when the boot rash finally wore through, because it does with everything, I could easily touch it up.

A few other companies who helped out with some goodies were; Wiseco with a garage buddy rebuild kit for the motor (with the correct crank), Limited Decal with a full set of graphics, Mika Metals with handlebars and chain / sprockets, DT-1 with air filters, Factory Connection with a great suspension setup for the woods FMF Racing with a Fatty pipe and Shorty silencer and Galfer USA with brake components to get us slowed down.

When I got back from Minnesota at the end of March I had stripped frame that was ready for coating, what was left of useable stock parts cleaned up and ready to go, a pile of aftermarket goodies and a puzzle that is supposed to be a motor and transmission when assembled. A few hours after work everyday I quickly had what resembled a dirt bike. It was also at this point where I realized I had a bunch of little odds and ends that were missing. No worries, I ordered a few more parts and in the mean time fabricated up a few small things like exhaust mounting brackets and case savers.

At last, a bike that runs, moves and stops! Well, a bike that mostly runs and moves. I chased a carburetor issue for much longer than I care to admit. Also, on the first real ride of the bike I lost second gear. Out came the motor and the cases were split. Turns out at some point in the past a washer had been lost and replaced with something of a much different thickness. This allowed the gear to slip and did enough damage that second was no longer a thing. My solution to that issue was finding a complete transmission on Facebook Market place. Cleaned it up and inspected everything, slapped the motor back together and we again had a running shifting dirt bike. The carb issue was solved with the help of Trail Rider Magazine’s own, Kurt Flash. He recommended trying a Lectron and he told me where to go to get one. Right out of the box it was much better and after a little fine tuning it was a whole new bike!

The day I got the suspension back from Factory Connection I also got the announcement that the 125 All Star Class had been cancelled for the year due to restrictions with Covid. I now had a finished bike with suspension setup for pro motocross and nowhere to race it. I did what anyone would do, I decided to race it myself at some J Day Off-Road events. I set the sag for my weight and basically adjusted the compression all the way out and hit my local woods loop. I was surprised at how well it did in the woods. I would deflect off of a few things because it was pretty stiff but it was very predictable and the fast I went and the harder I hit the better it worked.

I put about 9 hours on the RM and I only raced it 3 times. More often than not this bike would tag along to races or events to sit on a stand and look pretty. This was not what I originally had in mind but it was usually the best option as I was either helping as a mechanic for other racers or there simply wasn’t a class for it to be competitive. Rather than watch it collect dust I decided to sell it to someone who would be able to ride it more than me. A friend of a friend ended up finding out about it and decided to take it off my hands.

All in all the entire project was a lot of fun. Every step of the way was an experience. There were lows like the transmission failure and the class being cancelled and there were highs like hearing it run for the first time, getting to race what started as a rusty frame and a pile of parts and meeting a new riding buddy when it got sold. I am already looking forward to having a blast building the next project.

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