A7 head Identification

[KeithA]

Can anyone advise what type of head I have
It came off my 1952 A7 star twin
Thanks Keith

[beezermacc]

I don't have any cylinder heads with this number. My A10 heads are 67-251, my A7 heads are 67-381. If you measure the domes the A7 head is 66mm, the a10 head is 70 mm. Maybe send a few extra pictures of the whole head, not just the part no.

[BSA_54A10]

Not being one to reinvent the wheel you can find the information on heads on this site
 http://atlanticgreen.com/a10alloyhead.htm

[KeithA]

Thanks for your reply
I had pictures of the complete head, but had to crop them down so they were under 1500kB unfortunately
I'll have to work on this and send another set of pictures
Keith

[beezermacc]

Thanks for your reply
I had pictures of the complete head, but had to crop them down so they were under 1500kB unfortunately
I'll have to work on this and send another set of pictures
Keith

Open your picture in 'paint', reduce the image size, then resave and post.

[chaterlea25]

Hi Keith,
heres a link to a free photo resizing program.

http://www.faststone.org/FSResizerDetail.htm

it will reduce the image so it can be posted on the forum
Another method is to select a lower image resolution on your camera
If you use an Iphone, you can email the image to yourself and it will ask you to choose the  size of image being sent
HTH
John

[trevinoz]

That would be an A10 head.

[KeithA]

A better picture than the ones posted before.
I was able to resize the photo using "Faststone"
Can anyone identify the head for me please.??
Keith

[trevinoz]

Keith, that head is definitely an A10 one.
The A7 has a different number and has a small inlet port, just over 7/8"

[RichardL]

Following Trev's lead, let me take you down to Google Town. (Doubt he would put it that way.)

http://www.obsoletebikeparts.com/a-38993243/twins-engine-parts/bsa-a10-twin-650-cc-cylinderhead-cast-iron-67-261/

Richard L.

[KeithA]

Thanks for all your help.
I finally managed to get some decent resized photos of the head that I took of my 1952/53 A7 star twin.

[duTch]

 Keith, I don't know at all, but going by the information at hand , it seems you have an A10 head on an A7 Star Twin   

[olev]

Keith,
My parts book (1949 to 1953) says:
A7 head - 67-380
A7 and star twin head - 67-524
A10 head - 67-250
long stroke A7 head - 67-24
long stroke star twin head - 67-182
The head off my 52 star twin is stamped 67-381 which I think is original.
You seem to have a later A10 head.
What is the measurement of your bore?

cheers

[KeithA]

Thanks for your help
Yes this head came off this barrel when I bought the bike recently.
The bore measures 67mm (approx.)
The motor was running, and the bike rideable no problems at all.
I posted a picture of the bike also, before I stripped it down.
Thanks Keith