Author Topic: Aluminium head for a plunger....  (Read 560 times)

Offline Resto-Rob

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Aluminium head for a plunger....
« on: 24.05. 2014 21:53 »
Hey guys,
Just wondering if anyone has ever fitted a alloy head to their A10 plunger??
I've been told the later model A10 heads wont fit so im thinking of casting my own up....
I like the idea of better cooling and running larger, shallow angle valves to increase flow....  What do you guys think??
I know i will probably have to mess with the carb and exhaust to keep everything everything in balance as well....
Sounds like fun!!! :)
When life throws you a curve..... lean into it!!
1953 BSA A10 Plunger
1927 BSA S27
Austria

Offline Briz

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Re: Aluminium head for a plunger....
« Reply #1 on: 24.05. 2014 22:06 »
The alloy head will fit the engine with no problem, but the upward angle of the carb will cause frame clearance problems.
Cast one up by all means, but its a lot easier to cut the manifold off the head and weld it back on horizontally. Or convert to twin carbs.
The valve angles are the same on all A10s.

Offline duTch

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Re: Aluminium head for a plunger....
« Reply #2 on: 25.05. 2014 00:26 »

 I did it, is not hard but something of a time consuming challenge.
Made an extended inlet tract, picture(s) on here somewhere, kicked out to the left where the original filter/battery carrier goes- so then the battery needed a new home...have a drawing somewhere, if I remember later will have a looksee.
   
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
Australia

Offline Resto-Rob

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Re: Aluminium head for a plunger....
« Reply #3 on: 25.05. 2014 07:51 »
Brilliant,  thanks guys :)
I got told the stud pattern on the iron and alloy heads are different,  but i havent got an alloy head here to compare.
Was saying that the super rocket had shallow angle valves just a marketing ploy then??
When life throws you a curve..... lean into it!!
1953 BSA A10 Plunger
1927 BSA S27
Austria

Online muskrat

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Re: Aluminium head for a plunger....
« Reply #4 on: 25.05. 2014 20:50 »
G'day Rob. The early long stroke A7 iron heads are a bit different. The short stroke A7 and A10 iron/alloy same pattern.
The alloy heads use different bolts to the iron and different studs in the rockerbox.
The mod has been done by a forum member a while back, I did a search to no avail.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7