Engine noise - Does this sound OK?

Another possibility if you've adjusted valve clearances a couple of times recently is head bolt lost tension may be worth retensioning but must reset valve clearances after retensioning if they tighten up at all good luck

G'day Carl,
That appears to be a lot of clearance.
I run mine at .016 (4s cam) and they sure do clatter about.
I think way too difficult for anyone to make a judgement on noise from YouTube.
Check everything, be sure you'r reading the Feeler Gauges correctly. Metric or Imperial.
Don't compare your Norton engine sounds to a Japanese bike.
AC.

Hi Carl & welcome to the " My ears made me worry club". I'm no expert & sound over these devices is not of audiofile quality so I would say take it to a known NORTON mechanic to hear it. I've told this story so many times but it applies. As a teen I tore my 72 Commando completely apart (twice) because I "heard a rattling noise" after a 100 mile ride in 90 ' weather. I took it to a Norton expert after rebuilding & still having the noise only to have him laugh at me & say it's supposed to make that sound!!! Now I know it's chains & tappets etc that all make noise & may just be a little out of adjustment. Are you using a light weight oil like 10-40? Good luck.

A notable point here ~

I found that video taping a bike engine tends to accentuate the noises right off the get go !

I video taped my brand new rebuild Commando and the noises were horrible ~ and take the vidoe out of the equation and it sounded sweet as !

( Not that I am endeavoring to down state the potential problem here ~ just saying the camera tends to amplify the sound/s !)

In the name of peace of of mind check all out !

If I'm not mistaken that valve stem looks a little chewed up. Am I wrong?
May be time for a complete valve job.

Stillreel said:

That's the exact same noise I'm getting on my 68 TR6P (650). It drove me nuts for years but I've decided it's just a noisy bike. I actually replaced the lifiters but no change. Valve clearances is okay. And the bike pulls really well. So I'm just going to live with it.
BC

Click to expand...

yes but triumphs are notoriously noisy - in a good way according to triumph owners

back on track - i agree w/ cam chain or valves - but as mentioned these videos always seem to amplify some noise so hard to say really

Hard to really tell on internet...but ive always been told by the old timers that a little noise from the engine means its happy. If it gets real quiet or noisey..then worry.


Start simple and cheap first....valve gaps, oil type, primary drive chain tension, exhaust leak?...ect ect. before you do teardown.

If you ever, I mean, when you next take off the head, tap the head anywhere you like to hear its natural bell like tinkle tone. Be aware that there is an underlying clang/clink from the headers which goes away with exhaust wrap to reveal the more pure mechanical sounds up top. I'm not so sure we can hear the cam chain but likely its blending with the whirl/hum of the pinon/oil pump/sprocket cogs.

When I had my 1st Combat the ringadinging was a worry so I would putter along no throttle trying to hear if the ringadining was steady cyclic ok or intermittent random ohoh, when hear the OHOH of random extra ringadinging drop in heart, to suddenly realized I was being straffed by bats which being an ancient caver was just plain cool flashback, till they got braver entering almost under helmet and could hear it was the bats mimicking the Norton! This has happened a few times even to point they get entangled in headlight wires and cables so I had to help em out. All good omens to me but now deer so deadly thick I don't dare putter about at dusk if I don't have too.

So yes its normal they all sound like high pitched syncopated bat's mating or fighting calls.

Btw another benefit of the IS tank is it blocks a good bit of the header clang and the head ringabing so mostly hear the peashooters rumble.

Isn't that what all new techology is for, plug in a noise cancelling set of earphones under your helmet, turn up anything by Pink Floyd on your iphone or mp3 player, go for a long ride,and if (and only if)the bike finallys stops and breaksdown, you still have something good to listen to ease the pain and don't hear $$$$$$ sounds(ie cash register noises) ringing in your ears!!!
Regards mike

Listening to my own and others lets downs usually means a very few short revolutions before the stereo is all by its lonesome while waiting rescue. In other words if it runs at all and not hurt the ears likely good to go as real warning noises usually happen on the fly. Main symptom time to stop and renew is usually just less power and response if not extra smoke too.

Aw Matt will use about anything at hand, nicer stronger stuff available from major vendors like Rocky Point with SS versions.

It is hard to tell from the video but there is a chance it could be a fuel problem.

My owners manual from 1974 specifies 91 octane Regular. Last I looked regular is down to 88 octane and Premium 91 octane.

Do you know the octane rating of the fuel you are using and if it has been adulterated with Ethanol? It used to be possible to buy a bottle of octane booster but they might of banned that by now too.

Last I looked regular is down to 88 octane and Premium 91 octane.

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:shock: :shock:

Murray If I put 88 in my Commando or worse still the Trident ~ it would definitely sound like hell and High water has descended upon the bike ~

In fact I put a questionable amount of fuel into the Trident at a back water fuel stop on a club ride ~ and despite adding fuel booster when I struggled home~ the bike was NOT a happy camper and I had to drain it out and add a fresh load of 95 before it was again happy !

Here in Oz we chose can between <92 - 98> An extended road test by a very well qualified member of our bike group has put it down to <95-96 > being the most appropriate rated fuel for our classics ~

Hi Carl

It does sound a bit loud but they all do maybe not as loud but close to it, one thing I did notice is how blue your headers are that tells me you are running a bit lean mite have something to do with top end noise, as well when you had the caps off and moving your tappet it did seam to be a bit to much movement, but if your bike is running OK and not losing any power then I would just check your ajustments and maybe change your oil to a straight 50 grade, I have owned my 850 for over 35 years now and even when it was new it made top end rattles, but when I brought it new in 76, the dealer I brought it off was running GTX motor oil in it, but being my first british bike I didn't know better but with in 6 months the top end rattled and in hot weather here it ran hot then I started to run Penzoil racing 50 grade, my what a big diffrence it made.

But if you are still concern find someone that knows Nortons and see what they think.

Ashley

Yes , 09 or 100 octane ( 5 star ) were the go , in the day .

Shell race fuel or Av Gas isnt a bad idea in a new build engine , initial running .

Id see if the Rocker Arms are inclined to move sideways . Gentle push / sideways movement there would be a nusance .

Tappets are generally .040 a turn ( approximately ) so TEN thou , is 1/4 turn from zero gap , as a check .

sounds about like my Mk3 no louder no quieter.
>ok

[video]http://www.youtube.com/watch?v=hbVKRLFW2tg[/video]

I found that the timing chain was way slack > 1/2" of play. After adjustment it seems to me to be quieter. I made yet another vid but doing a comparison of the two videos it doesn't sound that different. I'm now probably somewhat deafer than yesterday....

after correct timing chain adjustment:
[video]http://www.youtube.com/watch?feature=player_profilepage&v=6VpJ5-05oDM[/video]

slack timing chain:
[video]http://www.youtube.com/watch?v=9Vv0ocfUbDk&feature=player_profilepage[/video]

I've acquired some straight 50W oil and will replace the oil and report back if that quietens it down some more. btw I' running 93 octane pump gas and it will have some ethanol content.

I have noticed that I do get some "chatter" when placing the stethoscope on the carbs. These are new flatslides has anyone else noticed something similar?

It is quite amusing to notice that something that is a tear down for some people is quite acceptable to others....

I never said NOT to tear it down, I said "No need to tear the engine down as a first step..."

Best thing would be for someone who has been around Commandos for a while to visit you and hear it first-hand to offer an opinion.

ludwig said:

GP is allready on his way

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Nope, I'm preparing for a home study tomorrow so we can finalize our adoption before Christmas.

I don't even know where he lives, anyway. Perhaps YOU should swing by...

grandpaul said:

I never said NOT to tear it down, I said "No need to tear the engine down as a first step..."

Best thing would be for someone who has been around Commandos for a while to visit you and hear it first-hand to offer an opinion.

Click to expand...

I'm glad I didn't start the tear down. btw: I've yet to come across another Norton. Paul - I'm down in Key West - it's T-shirt and shorts weather down here....

I changed the 20W-50 oil for straight 50W oil. It didn't sound too different but when comparing the sound to the original engine with the slack timing chain it does sound better.

after correct timing chain adjustment and switch to 50W oil.
[video]http://www.youtube.com/watch?v=mRwtAObZicg[/video]

the original - with slack timing chain:
[video]http://www.youtube.com/watch?v=9Vv0ocfUbDk&feature=player_profilepage[/video]

Maybe the incremental improvements have helped.

I'm now of the opinion it sounds OK (ish).