A rather worrying clonk!

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BigVeeGrin
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Joined: Wed Feb 17, 2010 1:41 pm
Location: Glasgow

A rather worrying clonk!

Post by BigVeeGrin »

Had this problem a while back but it went away, however, when running it appears that the engine 'misses a beat or similar' and is followed by a clonk/kick from deep down (the crank?). If stationary and the engine is idling it will cut out, restarting you get a bick kick, sometimes a huge backfire.

Any clues? Taking it to the guy who just did the CCTs to see what he thinks. But, big clonks do worry me!!
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sirch345
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Re: A rather worrying clonk!

Post by sirch345 »

They all do that Sir :wink:
If it's the spit back through the air box (under the petrol tank) from the carb then that is fairly common and nothing to worry about, although to be fair they don't all do it. What a lot do is increase the tick over speed to around 1400rpm's, that helps to minimize the problem. Having the carbs balanced (or do it yourself) may help if it's not been done for a while. Other things that make it worse are well used spark plugs and over the service limit air filter. If you have an after market exhaust fitted check all joints are sealed properly as that won't help either.

What type of CCT's did you have fitted :?: If they were the fixed type such as APE they could be adjusted a little on the tight side. That could be causing the engine to stall more than it would normally.

Chris.
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motorboat
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Re: A rather worrying clonk!

Post by motorboat »

Mine did this a few times in succession but hasnt done it since I replaced the CCT's yet. Sounds awefull but releaving its 'normal' lol
Pop, pop, bang, bang!
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BigVeeGrin
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Joined: Wed Feb 17, 2010 1:41 pm
Location: Glasgow

Re: A rather worrying clonk!

Post by BigVeeGrin »

Thanks guys - CCTs are manual type with a locknut, been on a fortnight.

By the sounds of it it's a firing problem rather than anything mechanical?
motorola222
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Joined: Thu Feb 25, 2010 1:12 pm

Re: A rather worrying clonk!

Post by motorola222 »

i get this.

turned out it was sticking choke slider and blocked pilot system i found redex helped but only true remide is strip down and clean and replace bits if nessacary.
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