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frank

HELP

1980 custome: I was riding my bike to work wen I started losing speed, then all of asudden she turns off on me, electrical is on but motor just wokn't turn over. I took it home and I took off the stator cover and I back wound the stator then pushed the start button and it wants to crank over but wen it gets to a certain point its just stoped. It probably is but I don't want it to admit but I think it has to do with the cylinders or the crank shaft. any ideas?

TOOLS1

Re: HELP

Administrator

Welcome to the forum. I hate to tell, you, but it sounds like it has an internal problem. If the crank will move, but not rotate a full 360*; it might have dropped a valve. I would start by pulling the valve cover, and taking a look. If, you do not have a manual, you can download it from our manual section.
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Re: HELP

Administrator

In reply to this post by frank

Re-run

Re: HELP

Administrator

In reply to this post by frank

Hard to say Frank. Just to make sure I have this right. You hit the starter and it moves but then stops dead?

Remove the spark plugs so you do not fight compression and put the bike in neutral. Use a socket and turn the engine over by hand. Follow the timing marks to make sure it is going all the way.
While turning, make note if you hit a grinding or clunking or anything odd. You will probably have a slight scrape all the way around but that should be normal. If you can, make a couple full rotations of the motor.
If you can do this, it is hard to say. Look at your plugs for any damage. Maybe change your oil and drop the pan and pump and check for metal shavings.

The ride IS the adventure. The destination is just to get gas!

frank

Re: HELP

Thanks for the tips. RE-RUN I took off the spark plugs and put in 4 straws I then turn the motor over by hand, and only 3 of the straws moved. So that tell me that that one is f**ked (excused the language). Sooo I'm gonna try and work on it myself

LukeM

Re: HELP

Administrator

Ouch. This won't be pretty. Sounds like a broken connecting rod. During the teardown, look at all the bearing surfaces and all the seals, just in case they need changing while you've got the motor apart.

On the upside, this is a good learning opportunity on Honda engine rebuilding. On the downside, it may get pricey depending on how much gets changed out and repaired. Good luck.

Luke M

Used to have a 1979 CB750L, sold it as a parts bike, now riding a slightly modified 1984 VT700C. Network/Field Engineer. Central OH, USA, Earth, Sol System, Milky Way Galaxy, Universe.