Bike in a Box 2- The Rolling 2003 YZ125

What’s gone down these last two months…

After my first Bike In The Box article went up, about 3 weeks later I started to receive the bearings from Pivot Works for the swingarm and the linkage. The bearings in both the swingarm and all the linkage components were rusted beyond hope of just regreasing them and throwing them back on the frame.

Once the bearings came in, I started to take them out of swingarm and linkage. Luckily the swingarm bearings came right out with no problem at all. I just popped the seals off and got the bearings out with a vice and some sockets. With the bearings out, I cleaned up the swingarm, which I wish was as easy as it sounded. It took a lot of contact cleaner, elbow grease, a razor blade, and a scratch pad to get the stickers and dirt off. I did the same for the linkage arm relay, but the linkage connecting rod took some extra help from some lubricating fluid to get the bearings out. While I was cleaning the swingarm and linkage, I had the replacement bearings freezing in my freezer. Once I had everything cleaned, I had packed the bearings with waterproof grease and slid them in with a vice and socket with no problem. The triple clamp bearings, surprisingly, were still good. They were only slightly discolored and all I did was pack them with waterproof grease.

Shock bearings were also a necessity for this rebuild. The old ones had been rusted just as bad as the other bearings on the swingarm and linkage. Pivot Works had once again sent me some new bearings. Luckily for me, replacing shock bearings was one of the few things on this build that I have done before. So replacing these bearings were easy for me. Same as everything else, I just used a vice and sockets to remove the old ones, then froze and installed the new bearings.

Then I focused my attention onto the forks. The seals were bad, and actually had a little bit of rust on the springs of the seals. Luckily for me, the seals were easy to replace. Save for a washer that fell out of one of the inner fork tubes when I was disassembling them. Being the inexperienced mechanic I am who is just kinda winging some of this stuff, I was freaking out cause I couldn’t find another one in the other inner fork tube. Until I got a good LED flashlight and saw there was a washer exactly like the one that fell out in the other inner fork tube. Once I found out my mistake, I had slid the washer back in the inner tube and focused my attention on to the outer fork tube. Both were covered in dirty, torn up stickers that just gave the forks a less than showroom quality look. No problem that a razor blade, a scratch pad, contact cleaner, and elbow grease couldn’t solve. With the outer tubes clean, the washers in the inner tubes, I began to replace the old fork seals with some new Pivot Works fork seals. Once I had the new seals in, I put them back together with no problem.

With fresh bearings and seals, and grease where it was needed, I threw all these parts on the frame to make a rolling chassis, temporarily. The only thing keeping me from keeping the swingarm on the frame is the fact that I need to put the engine in the frame still, and since the bolt that holds the swingarm on the frame goes through a hold in the engine case, I need to take the swingarm back off to put the engine in the frame.
Another little thing I did to this half bike in a box is that I cleaned the sub frame and the air box. Although, I scrubbed the air box a little too much and most of the black color had come off of it. Seeing how the plastic was still good, I just ran down to the nearest hardware store, bought satin black spray paint, and painted that air box to showroom quality.

The only thing that’s holding me up from throwing the engine back in the frame is that I’m waiting on the crankshaft bearings. Which should be here shortly after you read this. Other than those I have the new crankshaft, the piston with rings, and a complete gasket set. I have the case ready to split once I have those crank bearings. Once those are in though, there are still a lot of things I need to do to this bike, like how I need a complete new clutch, a cylinder and head, exhaust, hand controls, brakes, tires, and plastics. At least I’ll have the hard stuff done first.

I’m keeping a list of all the costs and just looking at it has me worried. A bike needing this much attention can get costly. But at least I’ll know it will be in perfect shape when I get all done.