convert 1960 gold flash to rocket

[stratcat]

So which bikes were the big valve head fitted to? I don't recall any mention of it in literature, apart from the american ad's of the day.

Was it an export only thing? or an extra cost option?

Just wondering.

[a10sausage]

i think the big valve heads where on the 1960s flashes and rockets..take a look at this   [url][http://atlanticgreen.com/a10alloyhead.htm/url]

[bsa-bill]

did a google and found this
-------------------------------------------------------
67-1549
This head is for the 1960/63 Super Rocket & 1962/63  Rocket Gold Star.  No visual difference from the 67-1126 head was detected.
The valves for 1960 and up Super Rocket were intake #67-1551 1.455" (37mm?), exhaust #67-967 1.38"(35mm?)
The inlet valve for the Big Valve Super Rocket and Rocket Gold Star was #67-961 @ 1.5"(oh wow).
-------------------------------------------------------
can be found at ---   www.atlanticgreen.com/a10alloyhead.htm

Anyway it's 45 thou - might make a diiference.

All the best - Bill

[trevinoz]

I am pretty sure that the big valve head was introduced for the 1960 season therefore was fitted to all Rockets. I am also sure that the inlet valve only was slightly enlarged and the exhaust valve stayed the same dimensions as previously.
As far as I know, the Flash valves never altered in size.
   Trev.
P.S.  The heads can be identified by the number cast into the bottom of the inlet manifold.
        67-1126 = Road Rocket / Super Rocket  1956 - 59
        67-1549 = Super Rocket, Big Valve head from 1960
        67-1571 = Late Super Rocket and RGS. the "49" was ground out and "71" stamped in it's place.
Not sure of the difference between the last two, the valves are the same, but I have seen reference somewhere to the inlet ports being modified, probably for 1962.

[trevinoz]

Bill, I think you will find that the 1.5" inlet valve was listed as an oversize valve and was not fitted during production.
Also, it is 45 thou larger.
             Trev.

[stratcat]

That's interesting.

I wouldn't have thought that 45 thou was a big difference either,

But then I am not an engine designer. So what do I know?

I am tempted to go out and check the serial no on my cylinder head.

Am I sad? Actually it's far too cold for that. I might just pour myself another scotch instead

[bsa-bill]

Now Sratcat I've just been down to my bottom shed to check the head number and it is  67-1549, might just join you with that dram  

All the best - Bill

[dpaddock]

Gullible, perhaps, but never "gullable", Richard L.
     David

[RichardL]

Help, I need a spell checker. Nevertheless, allow me to foist this specious definition to justify my college education:

gullable adj. One so gullible that he can be gulled by a gull.

I said it was specious.

Anyway, thanks for the correction Dave.

Richard L.

[stratcat]

...or, perhaps, pooped upon by one.

Isn't that supposed to be good luck!

[groily]

Last time I was pooped upon by one of these pests was in Castletown IoM - dropped a CB900F Honda (this is years ago) and 2 stone of kippers from Peel on the road back to Douglas later in the day. Memsahib moaned about all the broken ribs too - but she took most of the impact and the kippers were saved and stayed in their boxes. She said it was because I'd mouthed vulgarities in the general direction of Fairy Bridge. I suppose one makes one's own luck!

[stratcat]

she took most of the impact

That was kind of her

I bet that has cost you dearly.it would be horrible for something
Seriously though, it is my biggest worry when out with the mrs on the back. Pillions always come of worse and whilst I accept the risk for myself.....well it doesn't bear thinking about.