Author Topic: Annealing copper head gaskets  (Read 778 times)

Offline Swarfcut

  • Wise & Enlightened
  • *
  • Join Date: Oct 2018
  • Posts: 1274
  • Karma: 19
Re: Annealing copper head gaskets
« Reply #15 on: 11.07. 2020 08:08 »
  Jules. Cylinder base compression plates are available, but whether raising the barrel affects the valve timing to any detrimental effect is probably academic for now. Just nice to get it running without too much hassle.

 Swarfy.

Online Jules

  • Valued Contributor
  • ****
  • Join Date: Mar 2011
  • Posts: 304
  • Karma: 0
  • 1956 A10 s/arm Golden Flash
Re: Annealing copper head gaskets
« Reply #16 on: 11.07. 2020 12:40 »
Hi Swarfy, raising the barrels is an interesting alternative, I hadn't thought of that - probably because all my life has been spent on cars, which only has the block/head interface. Probably need to be a bit careful though because the barrels on the old models (mine) were a bit prone to failure due to the small thickness flange, if I remember correctly....
The barrel plates could be steel too which would be good down there, any idea who would sell them, did they have a part no. or were they just aftermarket?? cheers

Online JulianS

  • 1962 A10
  • Wise & Enlightened
  • *
  • Join Date: Mar 2017
  • Posts: 1076
  • Karma: 20
Re: Annealing copper head gaskets
« Reply #17 on: 11.07. 2020 13:35 »
Ebor motorcycle sell compression plates;

https://eborbikes.com/index.php?route=product/product&path=62&product_id=60

If you use one just make sure that the exhaust cam followers still actual touch the cam base circle. The slot in some pattern followers is not quite as long as the original BSA part.

Offline Swarfcut

  • Wise & Enlightened
  • *
  • Join Date: Oct 2018
  • Posts: 1274
  • Karma: 19
Re: Annealing copper head gaskets
« Reply #18 on: 11.07. 2020 13:43 »
 Jules. A Google search will bring up numerous suppliers, generally specialist solid gasket  guys knocking them out with modern laser cutters.  The snag with raising the barrel is that it alters the cam/follower relationship, also too thick will have the followers knocking on the follower retainers rather than following the back of the cam, as mentioned by Julian.

 The forum has details of how other folks approached the problem, and some of the pitfalls to what should be a simple exercise. The favoured alternative being a thicker custom head gasket. Plenty of posts and actual experiences of what works best. Your part of the world seems well served for custom stuff, and  recommended  suppliers are mentioned.

 Swarfy.

Online muskrat

  • Global Moderator
  • Wise & Enlightened
  • **
  • Join Date: Jul 2009
  • Posts: 8513
  • Karma: 112
  • Lithgow NSW Oz
    • Shoalhaven Classic Motorcycle Club Inc
Re: Annealing copper head gaskets
« Reply #19 on: 11.07. 2020 20:31 »
G'day Jules.
At 0.9mm the Ebor plates would be safe if everything is standard (cases/barrel flange not decked). I found anything over 1.5mm and you get the problem Swarfy describes.
Lani at Copper Gaskets Unlimited https://coppergaskets.us/ make gaskets in varying thickness 0.016" to 0.125". He even has a template for my special gaskets for my through bolted head/barrels. Reminds me to order more.
The beauty of a compression plate is the pushrod/rocker angles remain the same. With a thicker head gasket (especially if going extreme) the pushrods should be longer by the same amount.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Online Jules

  • Valued Contributor
  • ****
  • Join Date: Mar 2011
  • Posts: 304
  • Karma: 0
  • 1956 A10 s/arm Golden Flash
Re: Annealing copper head gaskets
« Reply #20 on: 12.07. 2020 02:36 »
thanks all, I think the Ebor plate will do the job, just need to find my old CR calcs  from years back when I did the engine build (I think its around 8.5 ish) *eek*..
I remember at the time that I changed the cam too because my std cam was well worn and a friend offered me a lesser worn RR or SR cam (don't know which, if they are different?), lesser worn meaning the peak lift was a bit down, but rest of lobe/bearings were good.
What are your thoughts on how best to setup timing etc since the rest of the engine is stock, iron head '56 Flash??
PS I know that all this is far from ideal but as long as it starts easily and runs smoothly, performance is what it is, its only for comfortable cruising really.....cheers

Online Colsbeeza

  • A's Best Friend
  • ***
  • Join Date: Aug 2015
  • Posts: 245
  • Karma: 2
Re: Annealing copper head gaskets
« Reply #21 on: 12.07. 2020 23:29 »
A fault I noticed after dismantling my Flash was that the old copper head gasket had punch overflow (for want of a better description). I dremelled it off before annealing.
This fault must have affected the head seal.
Col
Colsbeeza
Australia

Offline bikerboy

  • Valued Contributor
  • ****
  • Join Date: Dec 2011
  • Posts: 373
  • Karma: 4
Re: Annealing copper head gaskets
« Reply #22 on: 26.09. 2020 14:41 »
Firstly in my experience the thin flange barrels are fine provided the head steady is fitted properly and provided you are not going up to 10.5 to 1 compression ratio.

Secondly (ok I was young and foolish then) I had a similar issue when I was young and just fitted 2 head gaskets. They were both solid copper and properly annealed and that bike was on the road and used daily for about 15 years without any problems.

Before you all tell me what a cowboy I was  *smiley4* let us remember that this was back in the 70's, I had no money and even if I had of compression plates were not even in existence, well not in my part of the world anyway.

In those days you just got the damned bike running so that you could tear about like a lunatic with your mates :)

Offline BSA_54A10

  • Wise & Enlightened
  • *
  • Join Date: May 2008
  • Posts: 2055
  • Karma: 32
    • BSA National
Re: Annealing copper head gaskets
« Reply #23 on: 02.10. 2020 11:53 »
You do not want a mixture of metals at any joint face if possible, paticularly a hard metal like steel .
That way you have 3 different expansion & contraction rates to try and seal to prevent leaking at the crank case mouth.
So either use a soft thick copper gasket which will deform to keep a good seal or an aluminium spacer which will deform a little less but expand at a very close rate to the casting.
Bike Beesa
Trevor