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Author Topic: The ideal head job  (Read 3402 times)

leafman60

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Re: The ideal head job
« Reply #15 on: June 01, 2016, 03:08:48 pm »
Paul, if you are still monitoring this, what are your thoughts on pistons?  I have considered doing a head job similar to the one you show.  I have access to someone very good at this work.

In the process, I am considering a larger piston with better ring design.  What about the BMW pistons?  How large can I safely bore the stock cylinder and to what piston should I consider fitting.  This would also help the compression ratio.

Sigean

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Re: The ideal head job
« Reply #16 on: November 13, 2016, 10:22:02 am »
Hi,

I came across this thread some months ago, and having suffered the disastrous effects of a broken exhaust valve in my NF and the need to repair the damage to the engine, making some improvements along the way seem to be a good idea.  Could you just confirm that with the cylinder head modification you describe a standard (flat-topped) piston is run in the engine?  Any advice on the pistons to use?  By the way, could you tell me the make of the valves you used?

Sigean

banquo

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Re: The ideal head job
« Reply #17 on: November 13, 2016, 03:16:25 pm »
I don't think Paul's watching here any more (he didn't reply to Leafman's thread) and as he no longer owns an NF, I think we've had all we can ask of him. KenJ has his old bike, and I'm pretty sure the piston is stock, because the whole point was to reshape the combustion chamber to a more effective shape, and only a flat-top pistin will do that. As you can see, the Cylinder Head Shop did the work, inlcuding the twin-plugging and the valves. They might have records of what they used, or may recognise the valves from the photos.
Their valves are UK made: http://cylinderheadshop.com/valves-made-in-the-uk/

Sigean

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Re: The ideal head job
« Reply #18 on: November 17, 2016, 01:51:52 pm »
Many thanks for this.  I guessed the piston would be standard and I need to find one to replace the one with the big hole in it.  But this will have to wait as I need to "clear the decks" of other on-going projects (not least a Condor engine rebuild) before tackling the mighty Moto Guzzi. 

Kind regards,

Peter

banquo

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Re: The ideal head job
« Reply #19 on: November 17, 2016, 01:58:44 pm »
(not least a Condor engine rebuild)


huub

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Re: The ideal head job
« Reply #20 on: November 25, 2016, 11:08:58 am »
after trying to get a set of kibblewhite blanks i gave up and ordered a set of schrick valve blanks,
i will try and make some pics when fitting them.
with the cold weather over here i miss the falcone's wind protection.
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