Help! Bike death?

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Help! Bike death?

Harper.
I was riding up a pretty steep grade today, with a passenger, when the motorcycle back-fired and completely lost power. I pulled to the side and tried to start it again, but the electric starter did nothing and the kick start would barely move. Additionally, no lights come on, but the connections with the battery look fine. I'm worried that something is stuck somewhere in the engine, but I'm too new to know how to diagnose it, let alone fix it. Any suggestions?

thanks
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Re: Help! Bike death?

Harper.
A friend suggested that I may have skipped timing, and told me to check the timing belt for looseness. I should be ashamed of my ignorance, but is there a timing belt on these motorcycles? Is it the same as the camshaft drive chain? If so, how do I check it?

Thanks
Harper
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Re: Help! Bike death?

craigwadsworth
Yes there is, between the 2nd and 3rd cylinders running up to the overhead cams.  The tensioners are not hard to set, but if your friend is correct then you need to retime the valve train first.  You need to get a manual and make sure you have the right tools and parts.  If you have ever done a car then you should be able to do it, but you need the tech data first. There are many places you can download the files free if you search for them using Google or Yahoo.

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Re: Help! Bike death?

Re-run
Administrator
If you slipped your timing, then I would not just tighten up the CHAIN or belt. I would be pretty certain you have a chain though. If it got that loose, then it is a good bet it should be replaced.
Give us the year of bike and we can tell you more.
The ride IS the adventure. The destination is just to get gas!
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Re: Help! Bike death?

Harper.
Oh yeah, sorry, it's a 750 K5
Are there any common causes for a total engine lock-up like I had? And do they mean irreparable damage inside the engine?
Thanks,
Harper
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Re: Help! Bike death?

Re-run
Administrator
You most definitely have a cam chain. Can you put the bike in 5th gear and roll it?
The ride IS the adventure. The destination is just to get gas!
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Re: Help! Bike death?

Harper.
Ok thanks.
I can move the motorcycle in fifth gear a little if I have a friend help push.
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Re: Help! Bike death?

dave Esch
I had this same issue and the cause was not timing. I was on the freeway at about 70 and opened the throttle to pass. The rpms were up at about 6k and, like yours, backfire then death. I had no lights either. Turns out my main fuse was bad. That was it. I didn't see the link broken, but just for giggles I took out the signal fuse and switched it with the main and the bike fired right up. I have not had this issue since. But if you lost all electrical I would diagnose an electrical problem. Since this is my first bike, I don't dare disagree with the forum members, but I am curious as how a timing issue could affect electrical power.
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Re: Help! Bike death?

Re-run
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No you make a point there. Electrical is always something to check.
The ride IS the adventure. The destination is just to get gas!
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Re: Help! Bike death?

ccRider246
In reply to this post by dave Esch
Ditto, I had the same thing happen. It was the fusible link main. It broke but did not look broken. As soon as I unscrewed one side the break was obvious. I replaced the fusible link with a waterproof blade fuse holder from radio shack.
Chris
'81 CB750F
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Re: Help! Bike death?

rm56
In reply to this post by Re-run
Happened to me on my 74 one day. I rode down to fill it up, it was running perfect and as I turned a corner it lost all power and I pulled over. I pushed that heavy monster a 1/2 mile home only to find out the main 15A fuse had blown. Inside your main fuse cover just below the battery you should have a spare 5, 7.5, and 15amp fuse. Check the bottom one thats your main, a 15A. I put in a new 15A fuse and have had no problems since then. Oh and older Honda SOHC CB 750s have a timing chain not belt. They can wear out and stretch but I have never seen one jump teeth on a timing sprocket. Check that fuse.
I can see November from my house
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Re: Help! Bike death?

Harper.
Ok great, I'll check all these fuses. My question is, could a simple fuse problem cause the kickstarter to freeze? Or does that prove an internal problem.
Thanks
Harper
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Re: Help! Bike death?

Re-run
Administrator
The kicker does not move at all?
The ride IS the adventure. The destination is just to get gas!
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Re: Help! Bike death?

Harper.
Yeah, not at all.
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Re: Help! Bike death?

rm56
In reply to this post by Harper.
No your fuses have nothing to do with the kick starter. If it is stuck, jammed or frozen sounds like something broke interally. You can pull that side of the engine off and inspect it. You'll need to drain the oil, disconnect the clutch, and pull your brake and foot pegs off to get at it. Could be a spring snapped? Hard to say without pictures. This nabble site needs photos. I frequent several on line boards. And this is the only one where people don't post pictures. If you have a camera phone or digital upload photos so people can see what your talking about. It really speeds up the repair time. Good luck, hope its not too $$
I can see November from my house
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Re: Help! Bike death?

Harper.
Alright great (or terrible, depending on whatever broke inside), I'll check and post photos next time I can get upstate.
Thanks
Harper
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Re: Help! Bike death?

rm56
In reply to this post by Harper.
Seized engine
I can see November from my house