Author Topic: alu/iron  (Read 666 times)

Offline spyke

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« on: 30.04. 2011 12:14 »
Simple question ,are alu heads more likely to have head gasket problems than iron, everything being equal in the preperation etc?
Cheers Spyke
A10 spitfire style

Offline fido

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Re: alu/iron
« Reply #1 on: 30.04. 2011 17:35 »
No, I don't think any of the A7 and A10 models are prone to head gasket problems. Some people recommend using a solid copper gasket with iron heads and the composite sort with alloy heads.

Online BSA_54A10

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Re: alu/iron
« Reply #2 on: 30.04. 2011 21:58 »
Molecule for molecule, atom for atom, Iron heads are far more rigid than aluminium ones so are less prone to warpage.
Having said that I confirm Fido's comment.
A 7 & A 10 do not have inherit problems with their head gaskets till you start putting in really big pistons.
The only thing to watch is that you put some thick washers under the heads of the nuts on alloy .
Because the aluminium is less rigid than iron the bolt hole can collapse onto the stud which makes it very hard to remove the head & can lead to inconsistant clamping pressure between the head fasteners which will cause leaks.
Bike Beesa