Author Topic: In dire need of divine inspiration  (Read 2620 times)

Offline Roadrocket649

  • A's Best Friend
  • ***
  • Join Date: Nov 2010
  • Posts: 41
  • Karma: 0
In dire need of divine inspiration
« on: 18.04. 2011 13:12 »
Guys,

I would appreciate your ideas on this.

The bike is a 1958 BSA Super Rocket, which has ?Spitfire camshaft?, and  a 67-1549 cylinder head (1960-1963 Super Rocket Head and 1962-1963 RGS)

The engine has been totally re-built

The cylinder head, new valves & valve guides

The rocker box is on and lubricated with Castrol XXL40

The oil tank has not been filled because of the  following problem,

On operating the kick start, to set the tappets, on every 2nd stroke/ depression of the kick-start, I hear a ?TAP?

First thought to be from the rocker box, inspection covers removed and inlet & exhaust valves re-checked ? They were OK

I am using the inlet & exhaust valve clearances as of Page 46 Haynes Manual, where it states,
      Inlet      Exhaust
1960-1962   0.008?        0.010?

Not page 10 (Routine Maintenance & Capacities data where it quote 0.0008? for both inlet & exhaust valve

The I thought it might be something to do with the gearbox/ kickstart, and filled it with Castrol GP50

It is still there

I do not wish to start the engine, in case of doing damage

Any ideas Guys, I am in dire need of Divine Intervention?

Roadrocket649


Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5568
  • Karma: 65
Re: In dire need of divine inspiration
« Reply #1 on: 18.04. 2011 13:30 »
Hi 649
Have had a few problems of my own that were accompanied by a (tap or click), so a few suggestions that MIGHT be helpful

Valve sticking momentarily, the tap or click is when it moves again and takes up the slack in the tappet or cam follower
Front screws on the primary cover, if too long they catch the crank web when it comes around
Tappet catching the the rocker box cover

Others will have more suggestions I'm sure

Good luck with it
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 Roadrocket649

  • A's Best Friend
  • ***
  • Join Date: Nov 2010
  • Posts: 41
  • Karma: 0
Re: In dire need of divine inspiration
« Reply #2 on: 18.04. 2011 13:48 »
Hi BSA-Bill

Your input much appreciated

Definately not the front screws on the chain case - unwound them and "Tap" still there

Tap still there when rocker box inspection covers are off

Roadrocket

Offline MG

  • Resident Legend
  • *****
  • Join Date: Dec 2009
  • Posts: 949
  • Karma: 23
Re: In dire need of divine inspiration
« Reply #3 on: 18.04. 2011 14:56 »
The timing gears, expecially when mixed up from unmatched sets, can produce some sort of "clicking" noise (backlash in the gears).
1955 A7 Shooting Star
1956 A10 Golden Flash
1961 Matchless G12 CSR

www.histo-tech.at - Restoration, Repairs, Racing

Austria

Offline dpaddock

  • NC, USA
  • Valued Contributor
  • ****
  • Join Date: Jul 2006
  • Posts: 429
  • Karma: 5
Re: In dire need of divine inspiration
« Reply #4 on: 18.04. 2011 16:04 »
Put the bike up on its center stand and rotate the engine via the rear wheel in 4th gear. If you have a helper, you can easily observe the valve action. A sticking valve is a prime suspect as posted by Bill and can be readily seen in this way. This method will also eliminate kickstarter noise from the list of suspects.

David
David
'57 Spitfire


Online RichardL

  • Outside Chicago, IL
  • Wise & Enlightened
  • *
  • Join Date: Nov 2007
  • Posts: 5270
  • Karma: 50
Re: In dire need of divine inspiration
« Reply #5 on: 18.04. 2011 17:40 »
649,

MAYBE, take a look at this thread,

http://www.a7a10.net/forum/index.php/topic,3619.msg24950.html#msg24950

where our member Anji, in India, was having some valve noise. Don't know if yours is similar, but there is a lengthy discussion. Have you isolated the geography from whence the noise comes from by using a noise probe? Hopefully, not seen as self serving, I mentioned this in a post here (not like I am the only one to bring this up or use this technique):

http://www.a7a10.net/forum/index.php/topic,3619.msg24772.html#msg24772

Regards,

Richard L.
 
Plan on signing up for the world-wide 2020 DISTINGUISHED GENTLEMAN'S RIDEon September 27, 2020. This year it's a solo or pillion ride in dapper attire. Watch website at https://www.gentlemansride.com for details.


Online muskrat

  • Global Moderator
  • Wise & Enlightened
  • **
  • Join Date: Jul 2009
  • Posts: 8514
  • Karma: 112
  • Lithgow NSW Oz
    • Shoalhaven Classic Motorcycle Club Inc
Re: In dire need of divine inspiration
« Reply #6 on: 18.04. 2011 20:38 »
G'day Roadrocket649,
                             I'm with MG on this. Both mine do it. When winding over slowly there is a spot where the pressure of the valve springs force the cam backwards and takes up back lash in the gears. Once it's running it doesn't happen.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline MG

  • Resident Legend
  • *****
  • Join Date: Dec 2009
  • Posts: 949
  • Karma: 23
Re: In dire need of divine inspiration
« Reply #7 on: 18.04. 2011 21:05 »
I've just had another thought:

Did the full rebuild maybe include new conrod bolts and nuts?
I've recently rebuilt a bottom end with original rods and an ARP-made bolt and nut set (supplied by SRM). Unlike the older version they used to sell (supposedly for Triumph rods?), those bolts they are selling now are of the correct length and everything fitted perfectly well, but after assembly of the cases, I noticed that the nuts are slightly longer than the original ones and would hit the t/side crankcase around BDC!!!  *surpr*
A small chamfer on the nuts cured this. The new nuts have the hex over their full length, while the old ones had the smaller diameter locking ring on top, that's where the problem comes from.
 
I have reported that to SRM, and they promised to include a note to future sales. According to their workshop guys, this seems to happen on SOME, but not all cases, probably depending on wall thickness or something. Anyway, if it would just very slightly interfere, it could cause quite some noise without much resistance when turning the engine over.
1955 A7 Shooting Star
1956 A10 Golden Flash
1961 Matchless G12 CSR

www.histo-tech.at - Restoration, Repairs, Racing

Austria

Offline Roadrocket649

  • A's Best Friend
  • ***
  • Join Date: Nov 2010
  • Posts: 41
  • Karma: 0
Re: In dire need of divine inspiration
« Reply #8 on: 19.04. 2011 09:54 »
Hi Guys

Thanks for all the suggestions

Hi dpaddock, I put it in fourth, and turned the wheel, and the "tap" is still there so it is not the Kickstarter

I am waiting to get a friend to turn the wheel while I watch the valve action

Hi Muskrat & MG, the timing gears have not been changed and are the originals (as far as I am aware)

I will ask a stupid question here, how can you tell it is backlash in the gears, I suppose you have to take a chance and put it together and try it? (I would love it to be that)
The camshaft is a new SRM "spitfire " camshaft

Roadrocket 649

Offline Roadrocket649

  • A's Best Friend
  • ***
  • Join Date: Nov 2010
  • Posts: 41
  • Karma: 0
Re: In dire need of divine inspiration
« Reply #9 on: 19.04. 2011 10:01 »
Hi Manosound, I have read the thread you mentioned.

I have squirted oil along the rocker gear, and it is still there ( the oil pump has been re-built with new SRM parts)

The valves and valve guides are new

I have used your sound technique previously ( my father used to use a wooden headed screwdriver, but I was unable to turn the wheel and listen at the same time)

When my helper turns up, I will definately try it

Cheers

Roadrocket


Online muskrat

  • Global Moderator
  • Wise & Enlightened
  • **
  • Join Date: Jul 2009
  • Posts: 8514
  • Karma: 112
  • Lithgow NSW Oz
    • Shoalhaven Classic Motorcycle Club Inc
Re: In dire need of divine inspiration
« Reply #10 on: 19.04. 2011 10:09 »
Hay MG, great minds think alike. I thought about it today at work. I had a similar problem when I put a LJ crank in the '57 cases. But in my case the crank stopped when the nuts hit.
I'll still put my money on the back lash. The sound will be a "click, clock" coming from the timing side. To test wrap a bit of teflon (plumbers) tape around the idler pinion and turn the motor over. The sound will disapear or quieten.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline Mosin

  • A's Best Friend
  • ***
  • Join Date: Jun 2009
  • Posts: 245
  • Karma: 2
  • Cumbria
Re: In dire need of divine inspiration
« Reply #11 on: 19.04. 2011 12:56 »
Just a random thought, but are you certain that the tops of all of the pushrods definitely seated correctly in the cups on the rocker arms? IF one were resting on the edge of the cup and you had set the clearance with it like that, you may experience a click as it dropped down into the cup and then came out again as you continue to rotate the engine...

With regard to locating the problem, I have always found the sense of 'touch' to be more effective than the sense of 'hearing' in these cases. It is perfectly possible to remove the tappet covers and place the tip of a finger on each pushrod in turn whilst rotating the engine on the kickstart You should then be able to 'feel' as well as hear the click as it occurs which will at least let you know exactly where it is coming from.

I have always found this to be an effective method, And incidentally, yes, I do still have all my digits intact!
1960 A7 Shooting Star
1959 D3 Bantam
1994 Triumph Trident 900

North West England

Offline Goldy

  • Warwickshire, England
  • Resident Legend
  • *****
  • Join Date: Dec 2008
  • Posts: 619
  • Karma: 9
Re: In dire need of divine inspiration
« Reply #12 on: 19.04. 2011 17:29 »
I had a similar noise and it was one of the pushrods binding on the pushrod tunnel. When I dismantled I could see the mark on the push rod. They were alloy pushrods and I changed them for steel. All the best.
56 A10 Golden Flash - Restore, ride, relive.                                          
56 C12 BSA project ongoing

Offline Roadrocket649

  • A's Best Friend
  • ***
  • Join Date: Nov 2010
  • Posts: 41
  • Karma: 0
Re: In dire need of divine inspiration
« Reply #13 on: 20.04. 2011 11:44 »
Hi Guys

The "tap" appears to be when the Right Hand Side Exhaust valve is closing, although I can see no sign of a valve sticking.
Hi MG/ Muskrat, before I remove the Timing case, would the "tap" not be on every valve if it was idle gear / backlash, as opposed to just one "tap" with every four valve movements?

Hi Goldy, the bike did have four alloy barrel push rods in I got it
When I first took the head off 20 years ago, one was badly abraided to the depth of about 3mm
Definately rubbing against the channel
The others were OK
I changed that one for a steel push rod, and replaced them all in that order.
When I too the head off 10 years later, there was no further abrasion on the other three.

Cheers

Roadrocket649

Online bsa-bill

  • Wise & Enlightened
  • *
  • Join Date: Mar 2006
  • Posts: 5568
  • Karma: 65
Re: In dire need of divine inspiration
« Reply #14 on: 20.04. 2011 16:27 »
Hi again 649.
If you take out the spark plugs ( already out I bet ) and then remove completely the tappet adjuster for the right hand exhaust valve, fix the pushrod clear so it can't get into trouble while you kick the engine over, this would eliminate the valve or the click.
Funny thing it was the right hand ex valve that was sticking on mine *spider* (remember the Bruce)
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