Author Topic: engine knocks  (Read 606 times)

Offline Sasel

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engine knocks
« on: 09.08. 2015 18:31 »
Hello,

Could you please give me some advice. My Golden Flash likes to make a hammering metal sound when she is idling on half gas. no knocking on full throttel, just in the middle. So i change gears earlly. The engine is rebuild. Where shall i look?

Thanks from hamburg.

Yours Christian

Online RichardL

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Re: engine knocks
« Reply #1 on: 09.08. 2015 19:10 »
Christian,

Welcome the forum. Please look here http://www.a7a10.net/forum/index.php?topic=4723.0 regarding a first introductory post.

You've given sparse info regarding the knocking - near the top? near the bottom? Etc. First guest is that it's valve related.

Richard L.
Plan on signing up for the world-wide 2017 DISTINGUISHED GENTLEMAN'S RIDE on September 30, 2018. Watch website at https://www.gentlemansride.com for details.

Online muskrat

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Re: engine knocks
« Reply #2 on: 09.08. 2015 20:24 »
G'day Sasel.
My first thought is fuel related pinging. As Richard said, more info is needed.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, .
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Online Triton Thrasher

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Re: engine knocks
« Reply #3 on: 09.08. 2015 20:57 »
Try lifting the needle in the throttle slide. Put the clip in a lower notch.

Online metalflake11

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Re: engine knocks
« Reply #4 on: 09.08. 2015 21:34 »
I had similar, it turned out to be the throttle slide in a very worn Monobloc! I run without a filter so the noise was more pronounced.
England N.W
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Online RichardL

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Re: engine knocks
« Reply #5 on: 09.08. 2015 21:39 »
Since there is a bent toward considering fuel: What grade fuel? What compression pistons? Lugging at low revs in 4th?

Richard L.
Plan on signing up for the world-wide 2017 DISTINGUISHED GENTLEMAN'S RIDE on September 30, 2018. Watch website at https://www.gentlemansride.com for details.

Offline Sasel

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Re: engine knocks
« Reply #6 on: 10.08. 2015 21:06 »
Thanks for your help. I use 95 octan fuel. I think the hammering is in the top of the engine. I am not shure. I can not here the knocking, when the bike does not drive.

Thanks a lot chris


Offline duTch

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Re: engine knocks
« Reply #7 on: 10.08. 2015 22:51 »

 Someone else had a similar issue not long ago, and a loose tank bolt was suggested. My RR tank bolt was completely stripped- I know the sound especially with an almost empty tank... *bash*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
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Offline renos-a10

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Re: engine knocks
« Reply #8 on: 11.08. 2015 13:41 »
Hi to all again,

 First of all i think you must check all the screw on the bikes and specialy tank . One day i riding my BSA A10 Golden flash and i hear i think the same knock like this one .
 Second you must check again the valves gap and next the piston  compression .

Good luck
Renos
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