Cylinder head exhaust threads

The 3 1/2 forum
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Parky
Posts: 5
Joined: 17 Jun 2019 19:42
Location: Newcastle UK

Cylinder head exhaust threads

Post by Parky »

Hello everyone. I’m a new member from the NE of England and have just bought my first Morini 3 1/2
It’s an amazing bike and I love it. So light and handles like a dream. My initial problem is that the exhaust threads on the front head have been butchered. Is there anyone who can repair them? Can they be helicoiled?
Any advice greatly appreciated.
John
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buzby
Posts: 190
Joined: 14 Apr 2006 18:31
Location: southampton

Re: Cylinder head exhaust threads

Post by buzby »

I had a repair done at http://www.lussoveloce.com/, the former North Leicester Motorcycles and it wasn't cheap and it took a long time but it cured my problem.
David
75 350 Strada, 76 350 Strada, 76 350 Sport. 80 250 vee, 72 Triumph TR5T and 81 Honda CB250RS
EVguru
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Re: Cylinder head exhaust threads

Post by EVguru »

I've been known to take on the task.

https://youtu.be/ZfFbA9Y3jHw
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
Parky
Posts: 5
Joined: 17 Jun 2019 19:42
Location: Newcastle UK

Re: Cylinder head exhaust threads

Post by Parky »

When you say not cheap, how not cheap was it?
davel182
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Joined: 18 Feb 2016 12:01
Location: Wolverhampton
Location: Wolverhampton

Re: Cylinder head exhaust threads

Post by davel182 »

The last time I had an exhaust thread repaired at NLM it was ~150 pounds and they pretty much insisted I bought one of their stainless nuts to ensure fit - another 40 (which turned out to be true as the original bronze nut did not thread nicely into the new port).

You might want to check out the work of Gini Mauro http://www.morinispecial.it/joomla/inde ... cle&id=177 despite the problem/cost of posting to Italy?
acemorini
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Location: Uckfield, East Sussex.
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Re: Cylinder head exhaust threads

Post by acemorini »

Hello Party,
Paul Compton recently repair a exhaust thread for me, very good service and quick and very reasonable, highly recommended.
Regards Pete.
Parky
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Joined: 17 Jun 2019 19:42
Location: Newcastle UK

Re: Cylinder head exhaust threads

Post by Parky »

Many thanks for your responses. The possible cost has made me try harder to sort out the crossed threads and with the help of a pal I have managed to get the nut fully home.

Not sure if it will work again but for now the problem is resolved
Thanks again
3potjohn
Posts: 1243
Joined: 02 Jun 2007 13:58
Location: Devon

Re: Cylinder head exhaust threads

Post by 3potjohn »

I made good and sure that my threads were cleaned of any carbon or other residue and then used the same grease I use on my beemers.So far so good....
John
julianharty
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Location: High Wycombe Area (Bucks)

Re: Cylinder head exhaust threads

Post by julianharty »

John, which grease do you use for your exhaust threads please?
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Ming
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Joined: 01 Aug 2014 16:32
Location: France
Location: Central France

Re: Cylinder head exhaust threads

Post by Ming »

I use Molykote 1000, or failing that, Copaslip.
3potjohn
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Joined: 02 Jun 2007 13:58
Location: Devon

Re: Cylinder head exhaust threads

Post by 3potjohn »

I am sure any moly grease will do, the stuff I have is Optimol TA, I have had it for years. John
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