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Author Topic: engine makes large clunking sound when trying to start....  (Read 5852 times)

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Offline beks82

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engine makes large clunking sound when trying to start....
« on: July 24, 2010, 07:11:45 PM »
Hey guys 76 750F, I got it to start after reassembly but when pressing the starter button to start her up once in a while I'll hear this loud clunking/rattling noise...was wondering if this was normal or not...
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Offline vern401

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Re: engine makes large clunking sound when trying to start....
« Reply #1 on: July 24, 2010, 07:32:48 PM »
No it is not.. can you get a file of the noise for us? Maby one of us would be able to ID it for you.
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Offline beks82

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Re: engine makes large clunking sound when trying to start....
« Reply #2 on: July 24, 2010, 10:48:31 PM »
don't know how to upload recordings online....but i  guess the best way to describe it is it seems like something engages inside of the motor very harsh, which is the large clunk almost.  Then a whirring, and it seems as the engine is not being engaged.....
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Offline Hush

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Re: engine makes large clunking sound when trying to start....
« Reply #3 on: July 24, 2010, 10:56:08 PM »
Sounds like a starter clutch, can you check the starter motor is bolted on tight?
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Offline Spanner 1

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Re: engine makes large clunking sound when trying to start....
« Reply #4 on: July 25, 2010, 07:21:24 PM »
Hush plus one.
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Offline Terry in Australia

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Re: engine makes large clunking sound when trying to start....
« Reply #5 on: July 25, 2010, 07:25:49 PM »
Yep, starter clutch, probably the three 8mm phillips screws are loose. Buy some good 8mm "Unbrakos" and strip your starter clutch, inspect the rollers and springs, and re-install it with the new screws, and it should be fine. Cheers, Terry. ;D
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Offline beks82

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Re: engine makes large clunking sound when trying to start....
« Reply #6 on: July 26, 2010, 03:29:30 AM »
thanks guys for all the replies.  strange thing is today there were no problems, checked the starter motor and it's on their good and tight.  is it possible that a starter clutch would slip out if a battery was undercharged?  I have inkling that i may need a new battery....
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Offline Hush

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Re: engine makes large clunking sound when trying to start....
« Reply #7 on: July 26, 2010, 02:11:10 PM »
No I doubt it is your battery.
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I think the thing I most like about motorcycling is the speed at which my brain must process information at to avoid the numb skulls who are eating pies, playing the ukulele, applying make-up etc in the comfort of their airconditioned armchairs as they make random attempts to kill me!!!!!!!

Offline beks82

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Re: engine makes large clunking sound when trying to start....
« Reply #8 on: July 27, 2010, 12:29:53 AM »
okay, so then I'm stuck on the starter clutch, does it need to be replaced or can i just tighten down the bolts and be done with it? 
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Offline Terry in Australia

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Re: engine makes large clunking sound when trying to start....
« Reply #9 on: July 27, 2010, 04:51:33 AM »
You'll need to remove your rotor to check it mate, quite often the screws will be damaged, so it's best to buy 3 new 8mm unbrako's. Also, look for damage to the starter clutch's outer steel case for damage, I've seen rollers bashed back so violently they've been shoved up through the outer case. Also check that the little springs are intact, they take a pounding too. Cheers, Terry. ;D
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I was feeling sorry for myself because I couldn't afford new bike boots, until I met a man with no legs.

So I said, "Hey mate, you haven't got any bike boots you don't need, do you?"

"Crazy is a very misunderstood term, it's a fine line that some of us can lean over and still keep our balance" (thanks RB550Four)

Offline kenolds

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Re: engine makes large clunking sound when trying to start....
« Reply #10 on: July 27, 2010, 06:52:01 AM »
Sorry you are having trouble with the starter clutch.  If you want to see what a fully functional assembly looks like, then just give me a call (Ken from Alpharetta).  I would also like to see your bike and maybe help you troubleshoot.

Best of luck,
Kenolds
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