Author Topic: 1977 cb750F issue!  (Read 528 times)

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Offline cbstevef

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1977 cb750F issue!
« on: May 27, 2012, 07:50:20 AM »
Not sure if anyone will be able to help me but I thought it would be worth a try to throw a question up on the board! I was recently riding and I started to hear a loud ticking noise not to far from home. once I got home I shut the bike down right away and later found that one of my valve nuts came loose and was somewhere inside my engine. I ended up having to pull the engine out of the bike to retrieve the nut. I only removed the valve cover and two of the side covers but never separated the engine. We returned the motor to its rightful place and reassembled all of the components. To make a long story short my bike would not start anymore. I did have a bit of a starting issue before this valve issue but it always started up with a few extra turns and a little throttle when it was cold. the starter cranks over now but the engine doesn't fire. There is spark but I believe it is an issue with fuel delivery. THere are still a few things i need to check to resolve that but the main issue now is that when I tried to kick the bike over after my battery started to tire out it hits a spot during the kick that you cannot pass. Not because of high compression but because of an obstruction I think. you can hear it hit something that it cannot pass. The weird part is that a couple minutes before this kicking obstruction happened it kicked over fine. If anyone has any ideas it would be greatly appreciated. I know most everyone has a lot more knowledge about these bikes more than I do on this site so any input would be awesome!

Thanks,

Steve

Offline Old Scrambler

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Re: 1977 cb750F issue!
« Reply #1 on: May 27, 2012, 11:57:58 AM »
To be sure......I assume its a black motor F.  How many miles and is it original?  Just guessing but you may have a bent valve......When you re-assembled the rocker adjuster and set the clearance, did the adjuster have nearly the same depth as the others?

Charge the battery. If the motor spins freely (kill-switch to OFF) without abnormal sounds or ticks, the hang-up is likely in the kick-starter.
Dennis in Wisconsin
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Offline cbstevef

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Re: 1977 cb750F issue!
« Reply #2 on: May 28, 2012, 02:34:39 PM »
Don't think the valve is bent because the motor does turn over freely without any crazy sounds! Im assuming just a kickstart hang-up

Steve