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Bent fin straightening

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Grewth:
Don't you just hate bodgers ?
Today I have drilled out the sheared off exhaust port stud that was holding me up.
Now ordered a M8 Helicoil kit which should get me sorted.
It's given me a chance to take a really close look at the head.
Obviously one of the previous owners was some species of Primate,  possibly a Gorilla.
Anyone got any tricks or tips for straightening bent fins without breaking them ?
I think that they're probably going to have to stay bent until the head has to come off. [ Guests cannot view attachments ] [ Guests cannot view attachments ]

K2-K6:
One successful way (there aren't many) to re-bend aluminium alloy components is to heat locally while applying leverage.

If you can get a small flat lever in there (like an old bicycle one, thin and spoon shaped end) to get reasonably secure purchase, then use a blow torch to heat directly where the  bend is sighted, they will usually move.

You don't need much force else it'll snap. More feel by pressing on the lever and you'll feel it "yeald" as heat gets to threshold.  Its quite safe to try, if it doesn't move its not hot enough so don't lean on it like that.

I've always bent clutch and brake levers back to shape like this, in a vice with ring spanner over lever, play the heat on until you feel it go. It's genuinely very low force when you feel it moving though.

You could try for feel if you've an old lever to gently test the process and get your eye in before the critical fins. It is very gentle though to emphasise that, not much force but bring the heat up until it starts to "plasticine" and go where you need it.

Nurse Julie:
Gentle heat and a wedge shaped piece of wood will help. But, old alloy is brittle and the fin may still break as those bent angles are quite acute.

DomP:
I chickened out and left mine as a sign of a lived life and added character

Oddjob:
I’d need to fix that, it would bug the hell out of me. I’ve straightened alloy and it’s doable, just don’t rush it.

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