Featured Repairing Cracked Off Fins

Discussion in 'Technical Help' started by Pete1950, Jul 10, 2019.

  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.