1974 CB450 - maintenance, repair, and upgrade log

I've been slowly working on painting the tank and covers for my CB450 over the last year. This tank was a spare that I bought several years ago and the covers come from my parts bike, so I still have a set of black covers and a black tank that I can swap with these. I initially put off clear-coating the paint, wet sanding, and polishing last fall, but worked those steps in here and there over the summer. I think there's still a bit more polishing to do, but I had the bike out today and took a few pictures, so I thought I would share them in this thread.









My clutch cable routing is not according to Hoyle, but, since it seems like the cable has to go around the carb insulator either way, I've never changed it. Is there a good reason to route it on the inside?

stl360+450 said:

I've been slowly working on painting the tank and covers for my CB450 over the last year. This tank was a spare that I bought several years ago and the covers come from my parts bike, so I still have a set of black covers and a black tank that I can swap with these. I initially put off clear-coating the paint, wet sanding, and polishing last fall, but worked those steps in here and there over the summer. I think there's still a bit more polishing to do, but I had the bike out today and took a few pictures, so I thought I would share them in this thread.

My clutch cable routing is not according to Hoyle, but, since it seems like the cable has to go around the carb insulator either way, I've never changed it. Is there a good reason to route it on the inside?

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Did you do the stripes too? It looks good, I like the color. No special reason to route the clutch cable on the inside of the carb except that it's there from the factory (and IMO looks better behind) but since you have a black cable on it, it isn't as stand-out visible as it would be with a gray cable.

Hard to believe your summer is over already.

ancientdad said:

Did you do the stripes too? It looks good, I like the color. No special reason to route the clutch cable on the inside of the carb except that it's there from the factory (and IMO looks better behind) but since you have a black cable on it, it isn't as stand-out visible as it would be with a gray cable.

Hard to believe your summer is over already.

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The tank stripes are from 4-into-1 and went on fairly easily. They have black or gold stripes. The paint is House of Kolor: Galaxy Gray over Lime Gold. I can get rattle cans made up at my local supplier of SprayMax 2K clear.

It's good to know that the cable routing isn't making a functional difference.

After watching my CB360 fall over on the center stand last week (due to soft asphalt), I've been reevaluating my center stand preference and I found something troubling with my CB450. Last November, I swapped out my old, bent side stand for the spare from my 1972 CL450 parts bike as part of replacing my swingarm bushings and tidying up the centering of my center stand. With the bike on the side stand, I found that I could easily nudge the bike forward enough that the side stand would fold up, which would obviously allow the bike to fall over. I tried putting it in gear and there was still enough free play to cause this to happen. The side stand position is shown below. I think I would feel better about the side stand if it rotated a bit more, so the foot would be farther in front of the pivot point. I guess this is why it is important to put the bike in gear when parking on the side stand, especially in a public parking situation.

Actually, the picture on the left above shows the correct sidestand spring installation, the elongated end is designed to clear the pivot bolt head. I know the parts fiches aren't always indicative of proper assembly but in this case it is.



If you wanted the stand to be less likely to roll forward past the point of folding up, you could remove the stand and grind some metal off the frame's stopping point for the stand to increase the forward angle when it's down, and the further past center the spring goes the better it will help keep the stand down.

ancientdad said:

Actually, the picture on the left above shows the correct sidestand spring installation, the elongated end is designed to clear the pivot bolt head. I know the parts fiches aren't always indicative of proper assembly but in this case it is.

If you wanted the stand to be less likely to roll forward past the point of folding up, you could remove the stand and grind some metal off the frame's stopping point for the stand to increase the forward angle when it's down, and the further past center the spring goes the better it will help keep the stand down.

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I see you are totally right. I think I was looking at the spring on the center stand in the fiche I consulted.

I like that idea of grinding a little metal away to achieve a greater rotation angle on the side stand. This is something I could experiment with using my spare, untitled CL450 frame, too.

Last year I ended up swapping out the original spark advance mechanism with one from my 1972 CL450 parts bike. I had disassembled the original and was hoping to shorten or replace the springs and accidentally snapped the e-clips. The advance mechanism from the parts bike also seemed to have weak springs, so I shortened both springs slightly and I have been feeling that the timing was off at low RPM, especially before the motor has fully warmed up. It feels like the advance is reluctant to open and then opens suddenly at a certain point, rather than opening smoothly as shown in the manual.



So, this spring, I went through a mini-tuneup and adjusted the valves and static timing to see if the situation would improve. The timing was slightly advanced, but the cam/follower clearances were all at about 0.002", so no red flags there. Also no change in behavior after the adjustments. I then ordered an advance mechanism on eBay listed for 450/500T and realized after I got it that it was the TEC375 model for the 500T. Thanks to @Jays100, who confirmed that the TEC375 is compatible with the CB450s, I just installed that advance mechanism and the bike is running much better — the engine speed increases smoothly from idle on up with no hesitation as the advance mechanism opens.

I am waiting on a small order of tension springs from eBay with the ultimate goal of finding suitable replacement springs for the 450 advance mechanism. I probably won't hit the bullseye on the first order, but I will try to keep at it until a suitable replacement is found. This time I more or less made guesses based on a few caliper measurements, but I'll try to be more scientific about it going forward.

I had the 723B carburetors off for the valve adjustment and thought I may as well document things here for later reference. The float heights were 22mm (left) and 21mm (right), so I reset them to 20mm.

• main jet: 145
• pilot jet: 38
• slow jet: 38
• float height: 20mm

Another odd thing was that I noticed a slop in the shift lever while riding and found that the bolt on the back of the lever needed to be tightened. I checked my other bikes and it was still tight on my CB360G, but also needed to be tightened on my XL350. I should have paid more attention to that.

stl360+450 said:

Another odd thing was that I noticed a slop in the shift lever while riding and found that the bolt on the back of the lever needed to be tightened. I checked my other bikes and it was still tight on my CB360G, but also needed to be tightened on my XL350. I should have paid more attention to that.

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It's actually pretty typical for shift and kickstart levers to work loose a little bit now and then, it was one of the many little things my father taught me to periodically check along with other fasteners because of vibration. When you let them go too long it begins to wear the splines and it can lead to bigger problems, of course.