So I was missing some fins

[jacksonracingcomau]

On a nikasil cylinder from an LM2 1980 ish and had a chrome gone cylinder from an Ambo



upload pic


Now the hard part, to shape em up and stick em on

But, in the “every day a school day, never too oldto learn” vein
I discovered Ambo through studs open to fresh air, not in cast alloy sleeve as later

Looks harder to cast like this, to save two bob’s worth of alloy or have I got a freak cylinder here ?

[moto-uno]

  I'm finding it hard to understand what it is you're saying ?   Peter

[jacksonracingcomau]

Simplistically
I cut fins off Ambo cylinder to stick on Le Mans cylinder
Second photo self explanatory, the stud is (would be if assembled) exposed to fresh air, unlike later barrels which are not
This picture maybe better, cardboard is the fresh air ( and therefore rust on stud)
This is the bottom short stud exposed

[moto-uno]

   Gotcha  .  Peter

[jacksonracingcomau]

Maybe not up to Wildguzzi restoration standards
But good enough for the girls we go with






First train spotter that says that’s wrong, you can’t have 4 1970  fins on a 1980 barrel on a 1967 bike wins an anorak !
Interestingly , the “official” way to replace missing fins is to build with weld then hand finish, that would take hours and hours !

This a little more obvious but I like it, my mate Dean and his TIG are pretty good

[moto-uno]

  You're damn right he's good , and building each fin up with weld " who would even dream of something like that" ?
  Great to see a success story  .  Peter

[Moparnut72]

When I worked in the aircraft shop we fixed broken fins all the time. it would take the boss about ten minutes to build one up with the TIG. Would only take me about the same to shape it with a die grinder with Roloc discs. Broken fins were thenorm more thanthe exception, usually three or four on a cylinder. Radial engines that lived a hard life.
kk

[jacksonracingcomau]

When I worked in the aircraft shop we fixed broken fins all the time. it would take the boss about ten minutes to build one up with the TIG. Would only take me about the same to shape it with a die grinder with Roloc discs. Broken fins were thenorm more thanthe exception, usually three or four on a cylinder. Radial engines that lived a hard life.
kk

My hat is off
Seriously, I’m impressed, we didn’t beat that time cutting fins off old cylinder
But we used SFA gas and filler rod
For punters on here, price possibly more important than time
Fins missing from bikes more common than aircraft I’d guess, quid to be made here
If you can help others, not a bad thing to do