1976 Honda CB500T

Last year my son gave up on this bike and asked me if I wanted to give it a try.  He could rarely get it running and could never keep it running for very long.
I have no experience with motorcycles but decided to accept the challenge.
I am in the process tearing it down, cleaning it up, assessing what needs to be done, and getting it running and keeping the cost down until then.  In other words, little is being spent on cosmetics at this time until I see if I can get it working properly.
I’ve decided to keep a blog of my progress just for grins and to amuse my friends, but it occurs to me that perhaps if some folks who actually know motorcycles take a look at what I’m doing, perhaps some useful advice can be gleaned.  So, just in case anyone is itnterested, and cares to see how I’m going about this I’ll include the URL and maybe I can get some free advice.

Great looking project! You’re really putting some elbow grease into it.



How did the pistons and cylinder walls look when you opened up the motor? Did you happen to do a compression check. At first glance everything looks to be in decent shape.

I’ll give your blog a read. Thanks for posting!

The cylinder walls looked pretty good I didn’t notice any scoring or discoloring.  The tops of the pistons had some carbon build-up, as did the cylinder heads.  Didn’t do a compression check before I opened everything up…mistake??
I’m looking for a shop to mic the pistons/cylinders and check valves before reassembling.  I should do this right?  Also waiting on a gasket set I ordered.
Also, I’m wondering about cleaning the pistons and cylinder heads…any particular type of solvent I should look for?  How abraisive should I get?  Anything I absolutely shouldn’t do?

Wow! What a fantastic looking bike. You did a truly great job on it.

How is she running? Just as sweet as she looks I presume.



please take a listen to the video in the link and tell me what you think about the noise that’s almost like a backfire.  OK? Bad?
also, near the end of the video there is smoke that is coming from the area of teh prechamber. anything to worry about there?  it’s hard to see.
http://motorcyclediary-laprete.blogspot … t-now.html

Hey Iprete –

Sounds like there are a couple issues in the video. Number one – the bike is LOUD. You have no baffles. In my experience, you aren’t going to get any vintage air cooled bike to run well without baffles unless you put quite a bit of effort into jetting and tuning. If you are just looking for a bike to zip around town on I would actually recommend trying to get some real mufflers on there that provide some back pressure to the exhaust valves.

Two – Yes, sounds like you’re running only on one cylinder. This can be caused by all sorts of things. You definitely have a little exhaust backfiring. Pull your plugs after running, I bet one of them is wet. It’s either wet because:

A.) The cylinder is getting too much gas (stuck float, improper float height, way off throttle sync)
B.) There is no spark to burn the gas (bad spark plug, bad cap/wire, dead coil)

The bike is definitely looking great. Seems like you’re right on track. If you plan to keep it and ride a while I’d recommend a muffler that hasn’t been hollowed out. Even a cheap Dunstall replica will give you decent back pressure and help the motor idle smoothly.

Notes from a Reader:
Evanfell is 100% right. I have a Z750 twin which was doing the same thing. Gave the carbs a good clean through, changed mains to slightly bigger and baffled the loud exhausts. She runs sweet now. yours sounds like it’s definitely the carbs palying up

Evan Fell

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