Author Topic: Another tapping topic-sorry  (Read 915 times)

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Another tapping topic-sorry
« on: 08.10. 2018 13:20 »
Ok to start a list of what has been fixed/done to pre answer some replies  *smiley4*

1.Crank shaft reground and new big end shells
2. small end bearings checked and one replaced
3. reshimmed crank (2 thou)
4. New primary chain
5. valve clearances checked and set (8/10 thou)
6. All mounting bolts tightened

So now to the issue always tapping just like a to wide valve clearence esp at tickover. When accelerating sounds like small knocking but not. Can hear it as the power comes in then not as I go faster(could be masked by wind noise etc). No increase in vibration beyond the norm as in say a worn big end. Not a small end as I had that last year and it was horrible.
 Took the timing side apart and took off the dynamo chain no change in noise. Levered the crank no movement. No movement in idler pinion. Removed front valve cover no increase in noise.
 Ran over the engine with the screwdriver test and when put onto the rocker feed bolt for the exhaust feed the tapping could be heard/felt. So I am leaning towards cam/followers is there anything I missed??
many thanks Andy

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5315
  • Karma: 60
Re: Another tapping topic-sorry
« Reply #1 on: 08.10. 2018 13:37 »
just something that can be checked very quickly, slacken the three larger (front) primary case screws, they can (but shouldn't) sometimes reach the crank - not very likely but an easy one to eliminate
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #2 on: 08.10. 2018 14:24 »
Worth a try  *smiley4*

Online duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4444
  • Karma: 40
Re: Another tapping topic-sorry
« Reply #3 on: 08.10. 2018 19:10 »

 
Quote
  just something that can be checked very quickly, slacken the three larger (front) primary case screws, they can (but shouldn't) sometimes reach the crank - not very likely but an easy one to eliminate 

 One of the two inner case screws can do the same- but not so easy to check
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #4 on: 08.10. 2018 20:25 »
Well no change there. Doesn't sound like screws rubbig on the crank a definate tapping. I took a video on my phone I will try to send it to this topic.

Offline trevinoz

  • Newcastle, N.S.W. Australia.
  • Wise & Enlightened
  • *
  • Join Date: Jul 2006
  • Posts: 2829
  • Karma: 66
Re: Another tapping topic-sorry
« Reply #5 on: 08.10. 2018 21:49 »
It's not piston slap, is it?
What clearance do you have in your bores?

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #6 on: 09.10. 2018 09:38 »
Sorry didn't include in my list she had a rebore in the last couple of years and everything looked fine in spring when I took it down to do the crank.
She has horrible pinking but I can't  get the atu off due to the extract bolt not extracting,So I can't rule that out yet.

Online duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4444
  • Karma: 40
Re: Another tapping topic-sorry
« Reply #7 on: 09.10. 2018 10:31 »

 
Quote
She has horrible pinking but I can't  get the atu off due to the extract bolt not extracting,So I can't rule that out yet.

 Someone else had the same issue not long ago- if you do a search it may shed some lights (not many puns intended if there was any-except the ones I intended-if there was any)
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #8 on: 09.10. 2018 12:37 »
Found that thread(I started it :!)

Online Greybeard

  • Jack of all trades; master of none.
  • Wise & Enlightened
  • *
  • Join Date: Feb 2011
  • Posts: 5539
  • Karma: 29
Re: Another tapping topic-sorry
« Reply #9 on: 09.10. 2018 18:42 »
If you look back a month or so you will see that I had a horrible knocking that was a badly worn cam follower. I'd been adjusting the tappets and obviously taking out the slack but the follower was through its hardening and was rapidly wearing, opening the clearance.

Here's a link:
https://www.a7a10.net/forum/index.php?topic=13318.60

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #10 on: 09.10. 2018 19:02 »
Yes I remember your continuous bad luck like mine I must have had the bottom end down four times in the last two years.
It is something to check if it seems I have to take it down again. I haven't touched the cam etc for years it always 'looked fine. Strange the knocking noise is more obvious with the crash helmet on. With it off(Sorry officer) it sound  horribly rattlerly and with the exhaust covered not too bad???????

Online duTch

  • Ricketty Rocketty Golden Flashback
  • Wise & Enlightened
  • *
  • Join Date: Oct 2011
  • Posts: 4444
  • Karma: 40
Re: Another tapping topic-sorry
« Reply #11 on: 09.10. 2018 19:57 »

 
Quote
Found that thread(I started it :!)

 So is it stuck/broken again ? The thread I had in mind had a successful outcome and I think Beezamacc supplied a new gear
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #12 on: 09.10. 2018 20:25 »
I did have it fixed and I thought it was ok until I tried to remove it and it's not coming off again.

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #13 on: 09.10. 2018 20:28 »
I post so many problems I lose track🤣🤣

Offline BSA500

  • Resident Legend
  • *****
  • Join Date: Dec 2007
  • Posts: 699
  • Karma: 4
  • Tonbridge,Kent,UK
Re: Another tapping topic-sorry
« Reply #14 on: 11.10. 2018 08:56 »
Ok plan of action. After 21st Oct( I want to go to the Offham village meet cars and bikes) then I will try to remove the atu and retime the engine to exclude the pinking.
Then if that does not improve things when she is off road for winter I will start a gradual strip down checking everything in minute detail.