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Time for a re-do. I changed my mind about the looks of my CB550. It’s just not café enough. The remedy? Lower bars, different tank, cafe seat, mini gauges, and remove the mirrors. Yep, seriously.

The first big change had to be the seat. Café seats are typically shorter (solo seats), and incorporate a cowl to keep you from sliding off when you twist the throttle. I selected the Interceptor from Roc City Café Racers, along with the seat pad. It has a classic look, but also has a nice flat spot at the end of the cowl for a brake light. I have not yet permanently installed the seat, but it is shown mocked up in the pictures below. The cowl will give me a great spot to hide all the electronics/battery. I picked out a cheap tail light that I am thinking about incorporating into the seat. I also plan to relocate the license plate (again).

The stock CB550 tank isn’t terrible, but I really liked the looks of the CB500T (twin) tank. It is a bit larger, and just looks “right.” I happened to get a good deal on one in great shape. Just like the seat, I have not yet permanently installed the tank. I plan to move the front tank mount forward slightly, and then I’ll need to fabricate something to attach the aft of the tank. The petcock is in a slightly different location – it may be fine, but I might need to relocate it also.

The bars needed to be lower, but I wasn’t sure I was ready for clip-ons yet. I settled for a set of clubmans from Lossa. They aren’t quite as extreme as traditional clubmans, but still plenty low, and look better with the radiused joint. I removed the stock idiot light/handle bar clamp, and replaced with a simple set of handlebar clamps. No need to go aftermarket on the clamps, as Honda made them for other years/models. Part #95014-22200. I found my set on eBay.

The headlight wasn’t quite right either – it was too small, and too close to the bars. So I replaced the headlight brackets with longer ones, and went back to the stock 7” headlight bucket. The HID was really bright, but quite frankly I wasn’t too fond of all the “black boxes” need to run it. It also had a bit of glare. A big 7” headlight and OEM bucket just looks the “best.” I installed a Candlepower brand headlight with H4 bulb. No blue tinted BS here. The candlepower came with a quality Narva bulb, but I also bought a GE nighthawk just in case. My headlight ring/retainer was missing a few pieces, so I replaced it with a new one. My headlight bucket was also missing a few of the sleeves and screws that hold the headlight in, so I also had to order those separate from partzilla (3X each: #93500-050160B, #94111-05000, #61304-292-000). A few of the sleeves were a loose fit, so I just glued them in with 5 minute epoxy.

Stock gauges look goofy with low bars, so I opted to buy 2.5” mini gauges (60MPH @ 2240RPM for the speedo; 1:7 ratio for the tachometer). I have a larger than stock front tire, so my speedometer won’t be perfectly accurate, but that’s not a huge deal to me. The mini speedometer has LED idiot lights built in, which is why I got rid of the stock idiot light handlebar clamp. These things are probably made in China, but seem to be darn good quality. My only complaint is that the high beam indicator is super bright. For now I have the gauges attached to the stock gauge bracket locations, however they are too close to the headlight bucket, which is why they are sitting at a funny angle. I will most likely make a custom bracket that will spread them apart a little. Wiring them is mostly straight-forward, the only snag is the blinker indicator – you will need a couple diodes. I’m too lazy to sketch a wiring diagram, so I’ll try to describe it in words. Keep in mind the wire colors below are from my 1975 CB550, and may vary based on year/model:

Connect the following to ground (motorcycle green):
     Speedometer Yellow/Black
     Speedometer Blue/Black
     Speedometer Black
     Tachometer Black

Connect to +12VDC switched supply (motorcycle black):
     Speedometer green
     Speedometer red

Connect to +12VDC Illumination Circuit (motorcycle brown/white):
     Speedometer Orange
     Tachometer Red

Neutral indicator:
     Speedometer Green/Black to Motorcycle Light Green/Red

Oil indicator:
     Speedometer Red/Black to Motorcycle Blue/Red
 
High beam indicator:
     Speedometer Blue to Motorcycle Blue

Blinker indicator:
     Speedometer Yellow to cathode side of 2X diodes, and then connect motorcycle Light Blue to the anode side of one diode, and motorcycle Orange to the anode side of the second diode.

Note: Two diodes are necessary to make the turn signal indicator work for both L and R turn signals. The cathode side of the diodes (the side with a band) should connect to the speedometer yellow wire. Diodes should be sized based on the draw of your turn signal bulbs. Size the diodes using I=P/V, where I is current in Amps, P is power in Watts, and V is voltage. My blinkers each use 21W halogen bulbs, therefore the load is 42W per side. So 42W/12V = 3.5A.  Add another 20%+ for safety factor, and I come up with about 4.2A. I ended up purchasing some 5A 60V rectifier diodes (Schottky #SR560). Probably overkill, but overkill never hurts.

I also finally got around to installing spools on the swing arm. I have been using my aluminum rear stand with paddles for a while, and it always makes me nervous that the bike could slip off. Spools are much easier to use and much more secure. I bought a set of aluminum Vortex spools that use a 6mm SHCS. FYI the spools came with class 12.9 screws, and should be good to better than 2700 lbs each in single shear. I found a good spot in the swingarm on each side (see pics below) to drill/tap the M6 holes and install the spools. I did some very minor clearancing of the weld bead so that the spools would fit perfectly. The stand itself is a little on the short side, but I’m still able to lift the rear tire about 1/8” off the ground, which is all I need.

So beyond completing the tank and seat install, what’s left? Glad you asked:

Big stuff:
- Engine rebuild (plans include boring out to 600cc, a cam swap, and raising the compression ratio)
- Paint/powdercoat
- Rewire

Small stuff:
- Mini gauge bracket
- New steering bearings/conversion
- Lower front end
- Brake lines (probably need to be shorter now)
- Exhaust wrap


Here's a short video that shows the lighting/illumination on the mini speedometer:
 
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It’s been 6 months since I posted an update. Major changes are brewing, as you will soon see in the next update…

I started, but did not finish, the gauge restoration (more on that later). The stock gauges are fairly easy to pull apart – just carefully bend up the lip on the chrome crimp ring that holds the gauge halves together. The gauge guts appear to be in great shape, thanks mostly to the seals incorporated into the gage design. I won’t go into too much detail on the repair process, as there are plenty of guides on the internet/YouTube. The big things to address are the needles, gauge faces, needle damping pot, polish the glass, and clean/grease the clockworks.

The needles can be removed by pulling them straight off - be careful not to bend them! The gauge face is then held on with 2 small screws. I found that my gauge faces were slightly warped. So I first applied some heat with my heat gun, and then put some weight on them with a flat piece of steel to straighten them out as best I could. Next I wet-sanded the faces to remove all the old faded and cracking paint. I sanded all the way down to the plastic with a sanding block to further ensure the faces were flat.  Vinyl gauge face overlays (stickers/decals) can be purchased through eBay. Most are already pre-cut. I noticed, however, that the odometer/trip odometer slots in my faceplate were not real square. So I opted to contact the seller of the overlays and purchase the overlays without the slots pre-cut. This would allow me to cut them with a fresh razor after application, and ensure they matched the slots in the plastic face. Applying the overlays was fairly simple. I cleaned the plastic with alcohol first, and then sprayed with water, and squeegeed the face on (I used a credit card). Keep the protective cover on the outermost face (or put a paper towel over the exposed face) to ensure you don’t scratch the vinyl. After application, I sandwiched the faced under some heavy books for a few days. I then used a fresh razor blade to trim the slots/holes. The faces came out really good. In fact, my only complaint is that the overlays say “ND” (Nippon Denso) at the bottom, rather than “Nippon Seiki Japan.” Call me picky.

The white portion of the needles were actually in really good shape, and most people could probably get away with just re-painting the tips. You probably already guessed that I, instead, opted to re-paint the entire needle. I initially tried bead blasting a scrap needle to strip it, but the heat from bead-blasting warped the needle tip (and now you know why it is a scrap needle). The needles themselves appear to be made of copper. I ended up just scuffing my needles with sandpaper (carefully!), and using a toothpick to hold them into a block for painting. I’ve tried specialty needle paints in the past without much luck, so for this project I just used gloss white Rustoleum spray paint. The tips were done in Ace brand Fluorescent Glo Spray in “rocket red.” Regular masking tape doesn’t work well for small parts like this, so I just used scotch tape for masking.

The housing containing the glass is made up of 5 pieces, mostly seals (see picture), and can be disassembled by hand. With the glass out, it can be polished (if needed) with your favorite glass polish.

The gauge guts can be cleaned and lubricated (sparingly) with white lithium grease. At this point you should also consider re-filling the needle damping pots. These little containers, which couple the needle to the shaft, contain a thick oil to prevent the needle from bouncing. Over time the damping oil leaks/evaporates. This is also a reason why gauges should be stored facing up (damping pot cap up). Use 30,000 cSt (centistoke) viscosity silicone oil. This can be readily found, as it is commonly used in RC car differentials/shocks. The caps can usually be carefully pried off, and then the damping pot can be filled (use a syringe if necessary). Glue the cap back on when re-filled.

With all that done, the gauge can be re-assembled. Re-crimp the chrome crimp ring, and whala! If you couldn’t tell by now, I did not complete the gauge restoration, because I opted to change direction on which gauges I wanted to use on my motorcycle – more on this in the next update.

Other random stuff:
If you’ve kept up with my earlier posts, you will remember my trick fuel filter mod (mesh screen). I was concerned that it may get clogged and/or not flow enough fuel. Indeed, it worked great for a while, but finally got clogged enough to limit fuel flow. There just isn’t enough surface area to get the job done. Lesson learned. Long story short, I replaced the custom screen filter with an OEM filter, and now I’m back in business. The filter kit, complete with screen, seals, etc. are still available new. Part #16952-341-671. I got mine from partzilla.

You will also remember from a previous post that my K&L stick-on wheel weights started to fall off. I replaced them with some Motion Pro #08-0455 weights, and so far so good. These weights also blend in better, because even the adhesive backed tape is black in color.

I’ve been running cheap non-metric polyurethane fuel tubing for a while. It has held up well, but because it is not as thick as metric fuel line, spring hose clamps don’t work so well with it (and I hate worm gear hose clamps). So I found some metric (5.5 X 10.5mm) cloth braided fuel lines on eBay, and it did the trick.

I also finally pieced together a toolkit. I got a partially complete one from eBay a while back, and have been hunting for the missing pieces for a while. I found most on eBay, and bought a few new pieces from partzilla. I plan to incorporate a spot on the bike to store this toolkit, along with a few extra odds-and-ends.

I have also been keeping my eye out for finned engine covers. I got my hands on a racecrafters finned points cover. Still looking for a finned stator and clutch cover.