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6 Posts
Discussion Starter · #1 ·
So, I introduced myself in the not to distant past. I thought I'd start a thread into getting the old bike running. Here are some general pics.

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The history on this bike is I bought it in 2008 or 2009 and got it running. I had it going (just barely) and discovered that it had a crack in the right side cover. The crack leaked oil all over the rider's right lower leg. So, I fixed it with JB Weld and a beer can. It cracked again. The kick starter wobbled and the bolt would bounce on the cover and crack it. Based on that, I was unwilling to continue with it at the time. So, it sat for 10 years - that is on me.

A few notes as to how it came from the PO. It had the non-standard key/ignition. The starter button was gone. The tach was gone. It looks like the rear shocks have non-standard fasteners. And I'm not sure what else I'll find. There was/is a missing screw in the sprocket cover. The tach cable is gone.

I have decided to get this thing running. I'll be slow about it. I'm not an experienced mechanic. I'm pretty busy with other stuff. But, I'm up for it (I think).

So, step one was to get the starter button replaced. I don't want to be getting it started via the kick. I'm too lazy for that. The educated bike tinkerer would suspect that the starter was bad and that was why the starter button had been ripped off. I crossed my fingers. I put 12V across the starter motor (bolt to ground) and a whirring noise of sorts happened without turning over the engine. To my ear (which has never heard a failed motorcycle starter clutch) it sounded like a failed motorcycle starter clutch. So, off with the left side plate. To get the left side plate off, the right side plate came off to jam the main shaft drive pinion / clutch drive so I could crank the puller on the rotor. In the process, the sprocket cover came off, the header/pipes came off, the kick starter came off, the foot pegs came off, and I forget what else - it is in the bucket.

A few photos of the guts.

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I removed the starter clutch. It actually looks o.k. One of the springs is clearly kinked/buckled a bit. But the rest of the small components look o.k. No clear wear on the rollers. I don't know how I'd see wear on the caps. I've ordered new springs, caps, and rollers anyway. I'll replace it and see if it works. I'm not sure what else could be the problem. If there is some way there is wear up inside the outer clutch - maybe a "ramp" wears - I didn't take it apart to see. The screws were staked so I didn't want to mess with it. There seems no way the splined starter spindle could spin inside the pinion sprocket. Those spline teeth aren't great, but they'd be completely flatted if they were failed (I think). We shall see what that new parts do for the starter clutch.

Aside that seems to go here. I dragged a magnet through the drained oil. I picked up a fair bit of small metal bits. I didn't get a picture of that. Maybe next time. Let me know how important the metal bits are, or the need for a picture of said metal bits.

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Inside the right cover, things weren't great. You can see (below) the portion of the lower crankcase (inside red circle) that is not there as it has been nocked off by the tab on the kick starter spindle (inside blue circle). If anyone knows what that is supposed to look like, I'd love a pointer or other to let me know. Suggestions as to how to fix that would be appreciated.

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Moving on, I had to take the mufflers off to get at all the screws for the side plates. In the process, the headers came off. Looking inside the exhaust port, the amount of carbon and soot is significant. You can sort of see it in the picture below. So, what do you think about that? Rings bad? I don't really want to take it apart any more as my understanding is that pistons are impossible to find. Without the option of new pistons and an overbore, I'm relucant to get into the top end.

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So, some questions and advice sought.

1) Pros/Cons on getting into the top end to inspect the rings?
2) Based on that level of soot and carbon in the exhaust chamber, is this bike worth my trouble (I guess no 70s Honda, no less a CB500T is worth the trouble).
3) Suggestions on how to clean rust of the headers and pipes appreciated
4) Suggestions on how to clean grease, oil, and filth of the side plates appreciated.
5) What should I inspect, clean, replace, and otherwise maintain while I have it this far apart.
6) Ideas on the starter button. It looks just ripped off. I don't have a picture yet, but just the small button.

All suggestions appreciated. I'll be back though my change to work on the bike is infrequent so it will be a slow process.

Premium Member
10,203 Posts
Wonderful write-up. Last time I started to "clean up" something like that, at the end of the day I had the bare frame hanging from the rafters!

You can remove the head for cleaning/inspection without removing the cylinders/pistons, but better you wait for the DOHC folks to advise.

As for the rest of the bike, this will help:

3,204 Posts
Looks normal to me. A certain amount of carbon buildup in the exhaust ports is usual. An excessive amount can be signs of too-rich idle adjustments or a lot of slow speed running. Compression figures on an engine that has sat for a long time don't really mean a whole lot. Get it running, put some miles on it, then check the compression.
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6 Posts
Discussion Starter · #5 ·
Wonderful write-up. Last time I started to "clean up" something like that, at the end of the day I had the bare frame hanging from the rafters!

You can remove the head for cleaning/inspection without removing the cylinders/pistons, but better you wait for the DOHC folks to advise.

As for the rest of the bike, this will help:
Thanks. I plan to move through that lists slowly - but will likely hit all the items at some point.

6 Posts
Discussion Starter · #6 · (Edited)
Hello Hondatwins. Yes, it has been a long while. Various excuses. I'm back attempting to get my old CB500t running. Not much has changed from my original strategy. See if I can get it running. See if the compression is any good. Go from there.

So, from last time. The parts (springs, rollers) came in for the starter clutch. I installed them. The starter motor and clutch work and turn the crank. So, if I can manage the electronics and related starter button, that may work as a unit.

I removed the kick starter and will leave it off as it cracks the cases. So, in the meantime, I epoxied on another tin can over the hole to keep the oil in. Should work now and maybe forever. I picture of some of that is below.


Random aside on the condition. Below you can see the bits that are used for the helmet lock and saddle latch are gone (under the seat). Any help on ideas to rebuild/replace that are welcome.


Here is a shot of the right carburetor.


Here is a shot of the left carburetor. You can see some foreshadowing there. The bike set on the kickstand for a long time. More on that later.


Little shot preassembled featuring my cereal box gasket. Again, that is a temp. If things work, I'll do better gaskets.


Tank soaking with some vinegar in it. The tank was not too rusty.


The right carb cleaning. Pretty good.


Jets in some carb cleaner.

O.K. into the left carb.


Continued in a minute as I've hit the picture limit.

6 Posts
Discussion Starter · #7 · (Edited)

That goo is thicker than road tar. Very nasty. So, the bike sat for many years on the kick stand and I guess some gas leaked into the left carb. Or, maybe it was there already and the gas from the right carb spilled over? Anyway, very nasty.

A complication from the nasty carb is that the butterfly shaft/throttle is sticky. I cleaned it out and it worked, but it has grown sticky again as the carb cleaner dried. I'll have to fix that better at some point. It works o.k. now. I hope the throttle doesn't stick open and run me into something.

And yes, holes in the floats.


I'm sure this solder job will work flawlessly.



Some rust from the tank.



As an aside, the left side filter cover is missing. Any ideas for a replacement or solution?


I have a starter button and spring on order. We'll see if I can get that understood and corrected. With the loss of the original cluster, the ignition has been relocated, and may not be original as it has a bike key style key in it. Also, I have some wire attachment not attached to anything (green w red and white w red (or orange?)).

Anyway, back at it. Wish me luck. Suggestions, advice, support, hints, or criticism all welcome.
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