Project Blue Catch Up: Race Tech, Motor Parts, and other stuff…

No, I haver not been slacking. Not exactly. July and August are always rough for me with a few heavy lifts at the office. This throws off my progress. Still, I do get in a shop session here and there.

Race Tech Cartridge Emulators

Project Red used a set of progressive springs in the Forks. This is a pretty standard approach for airhead projects and they are a solid improvement over the OEM springs. They definitely stiffen the front a bit and provide a sportier feel overall. As I have put over a thousand miles on Red with them, I have learned where they are good and where they are a bit lacking. The feedback they offer is good overall, with a lot more sporty road feel. In the end, they are still springs. This means they can also be a bit “twitchy”, particularly in corners. Nothing dangerous, but they require consideration while riding. If you’re in a turn and hit something a bit uneven, you will need to manage their blunt nature and how that changes the front end handling.

For Blue, I wanted to level up the handling a bit. Enter Race Tech. They seem to be primarily focused on creating solutions for the dirt racing crowd, but have also produced-tuned street products as well. They make very custom, tunable rear shocks for pretty much any bike as far as I can tell and Blue had one of these when I acquired it. That shock was configured for the previous owner, so was not suitable for me. Race Tech also makes fork cartridge emulators that can be installed in traditional forks to provide a more modern feel.

Installing them is a bit daunting, initially. Because they are focused on performance and cater to a specialist customer, they aren’t the best at clearly communicating their product line to people who aren’t suspension nerds. No offense intended there. I am more than a bit nerdy in several areas, but suspensions aren’t one of them. I only mean that they expect to be able to communicate on a level that is not what your typical motorcycle rider is used to. This carries through the whole experience and you may likely run into some vocabulary and concepts that are new along the way.

The actual installation requires drilling new ports into your existing damping rods to effectively nullify the factory damping system. This is a fairly specific modification with variations based on the your specific bike, so it’s a bit more than what the average hobby mechanic might be comfortable doing. The whole process is the epitome of “measure twice, cut once” mentality. I 3D printed a work holding jig that would make using my drill press for this more predictable and repeatable.

The finished product looked good and I am eager to see how they feel once I have everything back together.

Cam Sprocket Install

One of the modifications I had done involved sending my new camshaft off with the cylinders and heads so my exact setup could be used in properly modifying the heads for my goals. When I bought the cam, I went cheap and did not get the version with a new sprocket pre-installed. This meant that I needed to do that myself once I got the parts back. This turned out to be another area where there is competing methods and airhead lore to choose from, and seemingly nobody had documented the actual process.

After researching what all the usual sources offered, I opted to use a method that was recommended by one of the characters in the airhead barnyard and regretted it immediately. That method was simple. Heat up the sprocket, apply a bit of red Loctite to the inside, place on the cam and you’re done. Easy enough. I used high-temp red Loctite, since the method involved heating the sprocket to something in the 500 degree F neighborhood. The problem was that the Loctite immediately cured and created an irregular coating of fairly solid goop on the surface, preventing any chance of getting the sprocket on the cam. Super.

Several attempts at removing this mess with solvents, heat, cold, and more all failed. In the end, it required an abrasive approach. If I hade a lathe, I might have been able to simply remove the material and retain the concentricity of the surface by slowly skimming it off, but I don’t have that option. ScotchBrite and steel wool were the solution. This cleaned it all off, but also will have changed the geometry of the part. Since this is a metal on metal part dealing with balance and alignment of the motor, I decided this was not acceptable and purchased a replacement sprocket.

The second method was a success. That approach was the same, but keeping the sprocket clean and dry for the procedure. I did put a bit of oil on the cam immediately before installing the sprocket. I also captured the whole attempt on video, which might just be the only version of this available online.

General Build Update: 2-Steps Forward…

More generally, I have begun the reassembly process. Because the past couple months have been so busy, I did not capture as much video as usual. Also, I am not sure anybody needs to see another version of some of this work, so it’s no real loss. Still, I have a few photos of the work and may have some of the wide-shot video uploaded as a time-lapse montage at some point.

Once the camshaft and sprocket were together, I got them installed along with the rest of the timing system, oil pump, flywheel and clutch. This meant the motor could be put back into the frame and I began working on the front suspension.

I am replacing the stamped steel top brace with a ToasterTan version, as I did on Red. This top brace is a bargain for what it does to improve handling, so I could not recommend them highly enough. Somewhere along the lines, I seem to have misplaced some of the required spacers for the brace, so I had to pause on the front while I wait for parts to arrive. This meant pivoting to the driveline install.

The gearbox and swingarm went in without issue, though I forgot to connect the neutral switch leads in advance (just like I did on Red) meaning that I will get to do this very fiddly task “the hard way”. Moving on to the rear drive, everything was going great until I decided to install all the plugs and crush washers. That’s where I found a disaster.

It seems that a previous service, or possibly even BMW since this is a 15K mile bike, over-torqued the swingarm drain plug. When I did the disassembly, I did not really examine the threads on these since it is a low mile bike but I recall some of the fasteners feeling a bit “elastic” and hesitant to come out. My initial assumption was it was simple buildup and was not bothered. When installing this plug, I noticed it did not want to thread properly and realized it was stripped. Great.

I’ve been very careful with this since I also noticed some questionable threads on the oil pan where I even retraced the threads of two of them to clean them up. This drain plug is likely unfixable though. I am pretty sure it will either need to be machined to accept a larger plug or possible get an insert. I am not sure what the prognosis will be, since this is a relatively thin area of the casting and it immediately abuts the internals of the drive. So this rear drive will be shipped off along with the one from Red for some expert evaluation.

As luck would have it, I took the opportunity to pick up a rear drive with 44K miles on it only a few weeks ago. That was intended to be either a spare or a replacement for Red if needed, but will live on Blue until the original is sorted. If the original is lost, I will have this one gone through professionally in the future. For now, it installed well and seems fine to my eyes even if it’s a bit ugly. It’s good to keep my military training in mind here: “Two is one and one is none.”

Electrics

I am still planning on the whole of the electrical system, but it’s taking shape. I did make the decision to abandon the original wiring completely. There’s nothing wrong with it, but I am adding enough to it that I would be making a significant number of revisions to the harness and I would rather just make a new one than relearn all the ins and outs of the factory wiring. I am going to be using a combination of the new EME/NWT R3 unit and some other circuitry for the aux lights and “farkles” I’ll be installing.

One thing that is underway is a side project to make use of the two dash blanks between the clock and voltmeter to add some much needed modern capabilities. I’ll elaborate more on this as it comes together, but it’s a side quest that is involving some custom PCB work and will likely be the most expensive part of the project in a manner of speaking. If it all works out, I hope to share it with the airhead community.

That’s about all for now. More to come as the project continues.

Some images from this work…