Sam Jacoby

Clutch Clean-up

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I’ve started tackling the clutch in earnest. They’re notorious in CB500s and Honda overhauled them in the 550. Mine has been giving me trouble on-and-off since I picked it up, but recently, it’s started to grow worse. It’s close to impossible to hit neutral while hot — which is pretty standard fare — but more troubling, the clutch hasn’t been disengaging while in first, so I’ve got to keep the engine revved to prevent it from bogging down. One hand on the throttle, one on the brake — not a good situation.

I started by breaking into the parts bike, just to get a sense of how the pieces fit together — which has been useful. It’s a bit nerve-wracking to begin wrenching without having any idea what’s in there (though I have the manuel), so it’s nice to have something to play with. Tackling the clutch has been a chore. The old gasket is just about fused to the crankcase, and it’s taking a couple of soaks with various solvents and a razorblade to clean it off. Nice and shiny now, though.

I checked out the clutch plates from both machines — neither were so amazing. I checked the steel plates for warping against a glass plate and a feeler gauge. They mostly seemed OK, actually, though according to many reports, that’s unlikely. The friction plates showed a bit more wear, but they also weren’t warped and basically good enough to use. More concerning was that their cork pattern was clearly not stock, nor was it any of the other well-known cork facings (square, etc.) I deglazed (I hope), the steel plates with some fine sandpaper. I also measured the springs, which looked basically fine.

Clutch basket laid bare.

Mystery friction plates.

Measuring over here.

In theory, these are fine.

I picked up some synthetic Mobile grease for no reason other than it was the most expensive, and I figured why-the-hell-not. Turned out to be red, which I don’t like.

The lifter assembly and bearing went in pretty smoothly. I found a new pushrod on Ebay — technically belongs to a CB450, but it seems to fit in there pretty nicely (same 8mm diameter), and it’s i good shape. Getting an OEM clutch cable was a good idea too. A clutch cable was one of the first things that I bought when I got the bike. Now, the better part of a year later, I know that it’s some non-OEM junk that’s not even close to the right length.

Beneath the clutch basket.

Replacement lifter (from a CB450)

Left to right: crap, old OEM, and new OEM

The whole thing came back together well enough, and though I wouldn’t exactly call my clutch smooth-shifting (the plates probably do need to be replaced), but it’s working well enough for now.