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It's a long way to 920 type(rary)

Discussion in 'Norton Commando Motorcycles (Classic)' started by yves norton seeley, Jan 14, 2018.

  1. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Hi,
    When the sleeves move in the casting, it was becouse I paint the barrels and put it in the oven at 200 degrees Celcius and I put the barrel with the bottom of the sleeves
    on the floor of the oven, so the casting go down along the sleeves, only a few mm, and no way to put him back by hand, I must use a hydrolic press to put him back in place and I discover no imbalance between the sleeves, no reason to look in this direction.
    To day I did 300 kms with the Seeley to a classic race in Holland, still with the 0.8mm cooper gasket, no issues so far...
    Yves
     
  2. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Dag Ludwig,
    I put steel Beleville washers under the trough bolts...
    Groetjes Yves
     
  3. ludwig

    ludwig

    Joined:
    Aug 30, 2006
    Yes , but I mean on top of the bolt , so that it sits flush , or slightly proud of the cylinder face .
     
  4. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    You mean between the head and cylinder?
    Yves
     
  5. rvich

    rvich VIP MEMBER

    Joined:
    Jul 25, 2009
    This is interesting. As I understand it, Ludwig is talking about filling the void left by the recessed bolt.

    Russ
     
  6. ludwig

    ludwig

    Joined:
    Aug 30, 2006
    something like this :

    [​IMG]
    a fraction of a mm above the deck .
    ( but with threaded hole to get them back out .. )
     
    Last edited: Jun 10, 2018
    Nater_Potater and cliffa like this.
  7. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    OK, I understand and will do it, thanks
    Yves
     
  8. CanukNortonNut

    CanukNortonNut

    Joined:
    Aug 8, 2005
    I have done your trick to my 74 Interstate. Thanks ludwig.
    Cheers,
    Thomas
     
    Last edited: Jun 10, 2018
  9. SteveA

    SteveA VIP MEMBER

    Joined:
    Dec 20, 2011
    Yves has answered this himself, both much earlier in this thread and in his recent answer. As he says, heat in the oven allowed the sleeves to move and a press put them back to where the should be. It is pretty clear that without such a lip there would be considerable risk of a sleeve moving with different expansion rates. Either the Maney alloy barrel or a cast iron one than has been sleeved has a lip on the sleeve and a counterbored recess to sit in, so the sleeve is clamped in place when the head is pulled down.

    Ken Kanaga has detailed the Maney barrels on a couple of occasions on here as well.
     
  10. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Hi There,
    To day I receive the Jim Schmidt .025" / .66mm cooper head gasket, but I don't know what to do: With the .60mm the result was fantastic and the gasket from Jim is .06mm
    ticker, so I have to 2 options: or I take .06mm from the head or I left the head like it is at the moment??? your opinion please...

    I alredy take the exhaust, carbs, oil lines and so on from the head, take all the bolts and nuts from the head off, give a tick on the rose to separate the head from the cylinder and call it a day.
    Tomorrow I will take the head out the frame and I will do the Ludwig trick: make some plugs to put in the cylinder bolt recess, Ludwig you are a genius!

    The most important thing I discover to day: I find the nut from the RH inlet valve adjuster on the floor off the head, just between the valves springs, I hope that I will not find any damage on the valve or pushrod...
    Keep you posted
    Yves
     
  11. Fast Eddie

    Fast Eddie VIP MEMBER

    Joined:
    Oct 4, 2013
    Leave it as it is Yves, you’ll not notice the effect of an extra 0.06mm on the gasket.
     
    SteveA likes this.
  12. jseng1

    jseng1

    Joined:
    Nov 26, 2009
    Why not try one of the .003" thick copper ring Head gaskets. Mine has been in about 5 years with no leaks (with pliobond and .005" copper wire).
     
  13. SteveA

    SteveA VIP MEMBER

    Joined:
    Dec 20, 2011
    Yes, I might look at that option again when I am trialling the alloy barrels. Numbers work OK. Will just have to be sure bolts/studs aren't bottoming. Though it is different hardware for Maney barrels anyway.
     
  14. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Hi There
    what I did yesterday and to day:
    First I make the decision NOT to grind the head, like Fast Eddy the difference between the .6mm and the .66mm is only .06mm, so let's try.
    Yesterday I make the plugs for the cylinder bolts recess and put the head on the engine, it is not that easy with the engine in the Seeley frame, but with the help from my friend John Dascombe we dit it, I torque the head and call it a day
    This afternoon I retoque the head, put all the stuff around the head, exhaust, carbs, oil lines and so on, make the valve adjustement, the bike is ready to start tomorow morning, I will warm up the engine 10 minutes, let the engine cool down and retorque the head again and do the road test.
    You remember that I found a counter nut from one of the inlet valve adjuster on the bottom of the head, I tchek the valves and pushrod's and don't find anything wrong, in fact the adjusting screw turn fully in the rocker and this keep the valve and pushrod save, thanks the Lord.
    I hope everything will be fine tomorow
    Keep you posted
    Yves
     
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  15. jseng1

    jseng1

    Joined:
    Nov 26, 2009
    If those plugs are .001" or .002" too tall its going to lift the copper gasket off the cylinder and then hot gasses can pass through and burn out the copper. Those alum plugs are OK for a composite head gasket that has some flexibility where the plugs can embed into the composite material. But they could easily cause a copper HG to fail. The fit would have to be exact and they should not protrude above the cylinder head AT ALL. When Ludwig mentions that his stand proud "a fraction of a mm" - that would be too much and would probably cause the copper to fail.

    I think Yves earlier failure was due to a copper HG that was machined. That would require sophisticated equpt to create a uniform thickness and if it had a thin spot it would have burned through as it did. I have never seen a copper HG made from unmachined sheet metal burn through (has- anyone else?). I think it would have been fine if it was made out of plain sheet metal. And his .8 HG held up no problem.

    Yves - I hope those plugs are exactly level with the cylinder surface - otherwise you might be looking at replacing that HG yet again.
     
  16. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Hi Jim,
    the plugs are flush with the cylinder surface, to day I made a road test with your .66mm HG, so far so good, same to have the power from the .6mm back
    I have to test different ignition timing in the next days and after go to the dyno to make the final adjustement on the carbs, if needed...
    I have some works to do on the Norton and the two Triumph from Jagbruno in the coming days also, still very busy like you see
    Keep you posted
     
  17. ludwig

    ludwig

    Joined:
    Aug 30, 2006
    I don't have sofisticated mesuring equipment , but as precise as I can mesure , a 3 mm thick alu spacer will compress about 0.1 mm under the nominal clamping force of the cylinder head , and supported by the bolt head , = a relative narrow ring .
    I have little experience with copper gaskets , but 0.03 to 0.05 mm proud should not pose a problem .
    I size them for each recess individually .
    BTW ,aren't the sleeves of a Maney barrel slightly above deck ..?
     
    Last edited: Jun 16, 2018
  18. jseng1

    jseng1

    Joined:
    Nov 26, 2009
    Yes the Maney sleeves are about .002" above deck - its Maney's way of getting a little more clamping pressure around each cylinder. But it could mean less clamping around the pushod tunnels where most leaks occur. A small amount of difference may not cause a problem. But there is a point where too much difference would cause a leak. To get the alum plug even with the surface you would either have to fine tune the plug thickness - or cut shims to go between the plug and the bolt head. Shim stock is available in many thicknesses down to .001" or even .0005" (1/2 thou). Shim stock seems the easier way to get it perfect. The last tiny amount of difference is going to get filled and sealed with pliobond - without it any copper HG can leak.

    The plugs look good and seem like a good idea - but I'm not sure if they are really necessary on a copper HG. I have never seen one blow out like Yves (except for the one Yves blew) and that one was machined and could've had a thin spot.
     
  19. ludwig

    ludwig

    Joined:
    Aug 30, 2006
    Jim ,
    the plugs are not intended ( not in the 1st place ) to prevent the HG from blowing , but to prevent blow by into the bolt recesses .
    I have often seen signs of blow by on seemingly tight gaskets , and bolt recesses filled with carbon and crud .
    Of course not after a few 100 km like Yves , but after higher milage .
    Still , looking closely at Yves' gasket , pretty sure it blew at ( because of ? ) the bolt recess :

    [​IMG]

    Sizing the plugs with shim stock seems complicated . I make them slighty oversize on a lathe , and then sand them to size on a glass plate .
    Doesn't take long ..
     
    Last edited: Jun 16, 2018
  20. yves norton seeley

    yves norton seeley

    Joined:
    Feb 13, 2014
    Hi there
    To day I did 100kms with the .66mm head gasket, the bike run very well, but I don't find the "itsy pitsy" power from the .6mm HG, should I try the JS .021" / .51mm with this gasket I will have a squish from between 0.9mm to 1.0mm??
    I also try with more advance, around 29 degrees in place of the 27 degrees before, a bit better but I am not satisfied...
    feel free to give me your valuable opinions please
    Yves
     

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