Featured Repairing Cracked Off Fins

Discussion in 'Technical Help' started by Pete1950, Jul 10, 2019 at 2:44 PM.

  1. Air cooled engines, especially older ones, often suffer from fins cracked off the heads and barrels - maybe from crash damage, maybe from ham-fisted mechanicing. Repairing them is not easy, but highly desirable.

    Today I collected a Moto Guzzi Le Mans head which had the fins welded up yesterday. The job has been done rapidly, efficiently, and as far as I can see effectively.


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  2. That’s pretty impressive. The only giveaway is that they are too clean at the moment, but that will average out pretty quickly.
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  3. I have bolted the head back on the bike and taken it for a ride today, to the Ace Cafe. It appears to work just fine, and looks a lot better than before.
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  4. Pete,

    Do you have any 'before' photos that you could share?

    Mr Bimble.
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  5. That looks pretty good.

    I used a two pack "liquid metal" filler (can't remember the brand) to repair a broken barrel fin on my MZ, it has held up pretty well....so far.

    It's off for a re-bore soon so shall see if it stands up to the stresses involved in that.
  6. The filler won't conduct heat very well - which is the point of the fins, really.