Very noisy engine

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Very noisy engine

Sprunghub
Yes I know they are naturally thus but this one sounds awful, clattering and rasping yet goes like the clappers, not the usual  noise that goes away when clutch pulled in (had one back in 1974 thus)  suspect timing chain, though someone mentioned "bob weights"?  what's  the ££££#s to sort out the former?
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Re: Very noisy engine

shinyribs
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Bob weights are usually the weight added to the crank during the balancing process to simulate and assembled bottom end. Unless you have a brand new crank that has never been balanced I doubt that's your problem.

Since your confident, and tested, that it's not clutch rattle, maybe you need the carbs synched.

Out of synch carbs and loose cam chains make some awful noises.
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Re: Very noisy enginemantle

Sprunghub
lol, have dropped a right clanger! tried to adjust cam chain, did no good so dismantled adjuster (K6 SOHC) was seized, free'd it off oiled it etc, tightened bolt and locknut with spring compressed THEN I tried turning engine  with a spanner to the plus 15 degrees ATDC, soon as I heard the loud click I knew what I'd done! chain had jumped sprocket, so now need advice re  setting camshaft to crankshaft, am told there are more than one mark on camshaft sprocket? (not had rocker box off yet) any advice welcome please
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Re: Very noisy enginemantle

TOOLS1
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First thing, remove engine. Then remove valve cover. Set crank to "T 1-4". Then remove the two 10mm bolts holding the cam sprocket on. Turn the cam to where the notch on the right end is up, and the lines on the end are horizontal with the cam tower. Then position the cam sprocket on the chain where the holes will line up with the holes in the cam. Then reverse order. When it's back together, to adjust the cam chain, just loosen the adjuster, then using the kick starter, or a wrench on the crankshaft, crank it a few degrees until you feel compression. Now tighten the adjuster. Done! Also since you are that far in, you should go on and change the rubber nickles, and O-rings under the cam towers.
TOOLS
P.S. you might want to do a search here for a thread "A tale of two cams"
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Very noisy enginemantle

cblover
I would agree with Tools1 suggestion. It may need some top re-conditioning.
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Re: Very noisy enginemantle

Sprunghub
So far so good, have got everything off the motor just the hanger bolts and "engine plates" to undo, the proper works manual makes it seem so easy, quote (step 13) unscrew the engine hanger bolts and nuts.  (no mention of supporting engine and risk of losing fingers)
step 14, raise the rear of the engine and remove it from the right,

Any advice on those 2?  take the weight using  wooden chocks or a jack? and when raised can it be slid out on wood, angle iron etc? or is it a case of getting a couple of sumo wrestlers round to do it? one last thing am changing oil filter, on removal a washer and spring fell out, know they go on before the filter, but what order? (not shown in workshop manual)     thanks
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Re: Very noisy enginemantle

TOOLS1
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The sumo wrestlers are how I do it. One guy on the left, and two on the right. As for supporting the engine, not really needed, as it sits on the bottom motor mounts. On the oil filter spring, and washer. The spring goes over the bolt, then the washer, and oil filter.
TOOLS
Life is not about the number of breaths, you take, but the moments that take your breath away.
I don't have an anger problem. I have an idiot problem. Hank Hill
Never confuse education for intelligence.
Happiness is a belt fed weapon.
I just can't imagine what could go wrong.
No fire? No explosions? So whats the point of your story?
Those who are too smart to engage in politics are punished by being governed by those who are dumber. ~Plato
It couldn't be done, but the darn fool didn't know it, and did it anyway.
We all got problems. Ksharp
I like vintage bikes because they take me away from the clutter of technology that I work with everyday and back to a simpler time of mechanical elegance and simplicity.. "ninadm"
Darkwing Duck: The worst part of public transportation is the Public.
"That is awesome shit there" Re-Run
"Fear nothing, attack everything" Eric Berry
" Oh, you read that on the internet? Clearly it IS a massive problem. Of course it CAN’t be normal operation."

1976 CB 750-A X 2
1977 CB 750-A X 4
1977 CB 750-K
1976 CB 750 F
1981 CB 750
1966 Kawasaki SG 250
1981 KZ 750 LTD
1973 CB 350
1979 CM 185 Twinstar
1982 Honda XL 80
South of Eden (Kansas City MO)
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Re: Very noisy enginemantle

Sprunghub
Thank you