Replacing the Clutch Friction Discs on a Honda CL450



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For this How-To we’re going to replace the clutch friction discs in a 1969 Honda CL450, but this procedure would work for CB450s too, and is similar on the 350s. We undertook this project because the motorcycle had been stored so long that the petcock leaked gasoline into the sump, and after fixing that problem the clutch slips. You will need clutch plates and possibly clutch springs, though those are rarely bad. A new gasket for the right side case would be useful, and a new seal for the kickstart shaft, if needed. If the oil sump plug O-ring is flat you’ll need to replace it too. Dime City Cycles will have some or all of these parts. You’ll need oil of the correct weight and amount also, in this case 1.8 liters of 10w40. A good set of metric sockets and wrenches, particularly 10, 12, 14, 17 and 19mm sizes. Start by draining the oil through the sump plug on the bottom of the engine. You’ll need a 19mm wrench, preferably a socket. Most of the sump plugs have been mangled over the years from people using SAE or adjustable wrenches in the place of metric. They also suffer from overtightening.- Keith Fellenstein


1. Using needle-nose pliers, remove the spring that actuates the rear brake light switch. This spring looks suspiciously like something found in the previous owner’s junk drawer, but it works.


2. Slacken off the brake adjuster nut at the rear wheel. A deep 14mm socket works to get it started, but you should be able to remove it by hand once the spring tension is reduced.

3/28/2021 2:35:51 PM

You're all correct of course and I knew they were JIS screws, but somehow that information didn't make it from my brain to my typing. Also correct about the impact wrench, another slip between brain and fingers. As for the oil flinger, I did open that up but it was too clean to make a useful picture.

3/19/2021 4:00:31 PM

While the clutch cover is off, it's a good time to clean any sludge out of the centrifugal oil filter.. This is often neglected.

4/24/2020 2:45:17 PM

As a former Honda mechanic I took many of these 450 side covers off. I used either a hand or air impact wrench to take the screws out, and a hand impact wrench to put them back in. A regular screwdriver won't put enough torque on the screws to keep them tight.

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