Author Topic: metallic knocking sound  (Read 2859 times)

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DAVE BRADY

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Re: metallic knocking sound
« Reply #15 on: 24 June, 2021, 07:42:24 »
Good morning,

Good news about the end float.  So looks like problem solved.  Good lick with it.

Dave.

mo goldie

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Re: metallic knocking sound
« Reply #16 on: 24 June, 2021, 22:39:13 »
Hi everyone

I am still in the thinking of do I do a complete strip down......as I am still not sure as to why them pistons were hitting on the flywheel after 2,300 miles after it had a rebuild before I got her...........do anyone think it is wise to strip it right down ?

Mo

DAVE BRADY

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Re: metallic knocking sound
« Reply #17 on: 25 June, 2021, 08:32:26 »
Hi Mo,

The horns of a dilemma I think.  The piston contact, which must have been there from the rebuild if there is no movement in the bearings and journals, is sorted.  So one option is to put it all back and ride it to see if it is all OK.  If no noise then ignore the bits of metal in the sump and problem solved. 
If there is still a noise then a strip down will be needed and where did those bits of metal come from.  If it was shim then it would be obvious and there would be more end float.  If not a shim then what?
Option two is strip it down and avoid the risk of doing serious damage if something fails.
I would go for option two as you have already stripped some parts off already.

Dave.
 

mo goldie

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Re: metallic knocking sound
« Reply #18 on: 25 June, 2021, 18:16:59 »
Hi Dave

Well I have convinced myself to go for option two..... as I want to find out what them bits were from if anywhere that is, unless someone was not careful in putting it back together and dropped some bits in when the barrels were off and something went in at some point.....anyway I think I will be more happy when I take it to bits to find out.....funny thing is I have had to do this to all my bikes when I have got them...which is to strip the engines and rebuild them at least I Know what has been done to them if you Know what I mean, thanks for all the help and in due course I will let you all know my findings  ;D

Cheers

Mo

mo goldie

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Re: metallic knocking sound
« Reply #19 on: 05 July, 2021, 22:07:19 »
Hi everyone

well here is an update..... I have taken the engine out and today split the crank cases did not find a thing of where the peace's come from that looked like shim,

but the primary side bearing outer came out without even having to heat the case up....also the inner part of the Bearing on the crank also I can put on and off by hand.....this is all a bit worrying as not had that before :-[

so any Ideas of what to do about that as I Know that is Not right........next job is to take the pinion off the oil pump side and have a look at the bush.........all seems Not good and it was meant to be put together by a gold star engine Specialist  ;D   

DAVE BRADY

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Re: metallic knocking sound
« Reply #20 on: 06 July, 2021, 07:12:13 »
Hi,

If the primary bearing fell out on its own then it could be more of a problem but if it still needed a bit of a tap or push then a good bearing retainer should sort that out.  The inner race on the crank could also be secured in the same way but if too easy to put on and off then the crank can be knurled a bit to tighten the fit and bearing retainer also used.  What make is the bearing?  There are some dodgy un-branded ones out there so replace it with a good one like RHP.

Dave.

chaz

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Re: metallic knocking sound
« Reply #21 on: 06 July, 2021, 14:50:03 »
as Dave says, check bearing make. I rebuilt a square 4 engine for a customer, he suplied the bearings he sourced from an Ariel specialist.
cases heated up old outer fell out, dropped the new one in and left to cool. on turning the case over the bearing fell out. RHP, Timken, SKF are my main choice at a push Koyo (oem for Japanese superbikes).
the main thing is C 3 class of fit, tighter tolerances. the ones for the square 4 were chinese and .003thou under size on outside diameter.

mo goldie

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Re: metallic knocking sound
« Reply #22 on: 06 July, 2021, 20:14:01 »
well just had a look at the Bearing and it`s a NTN NF 206E

But I will be replacing it for sure....oh also the cage the rollers are in is Plastic which I would rather it be steel or Brass..

So what is the best Bearing to use and what's the Numbers on it ? as I can check them out at my local Bearing dealer... oh I will be using Bearing Lock also dot punch the out race a bit as well as the Bearing Lock.....and someone said to dot punch the Crank Journal then put on the bearing with Bearing lock on it too.

How's every one think of that....?

Cheers Mo

DAVE BRADY

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Re: metallic knocking sound
« Reply #23 on: 07 July, 2021, 09:24:25 »
Hi Mo,

I have dug out an old RHP bearing and the number on it is NF206CN.  CN denoting standard clearance.  Some say use C3 as this can expand a bit more.  I am not certain if the original BSA spec was CN or C3 but I suspect either will be acceptable.

Dave.

mo goldie

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Re: metallic knocking sound
« Reply #24 on: 07 July, 2021, 21:06:21 »
Hi Dave

yes I did have that said to me today at the bearing company and they said they can get RHP or NSK. But what do you think about the dot punching to the crack to just take up a bit along with the Bearing lock which I got today ?

sorry to ask but do you know anyone that I can get a long split cone collet to replace to one that had Cracked in half as I
have tried loads of places and can`t seem to get one>

Cheers Mo

DAVE BRADY

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Re: metallic knocking sound
« Reply #25 on: 07 July, 2021, 21:27:32 »
Hi,

Dot punching the journal can work but it needs to be even or the bearing could be ever so slightly eccentric and the journal is hard.

Which split cone collet are you referring to?

Dave.

mo goldie

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Re: metallic knocking sound
« Reply #26 on: 07 July, 2021, 22:10:51 »
its the valve collet Dave ..sorry

DAVE BRADY

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Re: metallic knocking sound
« Reply #27 on: 08 July, 2021, 08:18:43 »
Morning,

Try C and D Autos 01564 795000 or email canddautos@gmx.co.uk   Probably best to ring them up.  They did have all the valve parts for RR and SR a few years ago and they carry a lot of NOS.

Dave.

DAVE BRADY

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Re: metallic knocking sound
« Reply #28 on: 08 July, 2021, 10:11:13 »
Hi,

Is this the one you are looking for?   SRM currently have 6 in stock.  If one has split it may be worth replacing all of them.

Dave.

mo goldie

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Re: metallic knocking sound
« Reply #29 on: 08 July, 2021, 22:19:46 »
Hi Dave

Just had a look at the SRM site and I think they look like the small type where the ones I am looking for are the longer type so I Might give them at C and D Autos a try....all the others I have had out and check to see if they were ok along with just grinding in the Valves at the same time.

cheers Mo