Author Topic: 1956 BSA A10 Road rocket Alloy Cylinder head  (Read 482 times)

Offline thackero

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1956 BSA A10 Road rocket Alloy Cylinder head
« on: 02.02. 2021 22:17 »
Assembling my 56 RR I appear to be short of the 3 short cylinder ALLOY head bolts. Does anyone have the part number. difficult to read in the 56 manual. Also noted that my manual does not show washers on the bolts  - is that correct ?

Offline DJinCA

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #1 on: 02.02. 2021 23:15 »
Hello Thackero,

I don't claim any expertise on this, so you may wish to wait for more knowing guidence.  Looking at my part books suggests that if you are asking about the bolt (and washer) crudely circled in red in the attachment,  The bolt part number is 67-283, 3 required and the washer is 2-2138, 9 required, suggesting that the artist didn't draw the rest of them into the image, and they should be used on the other head bolts as well as one might expect.

Hope this is helpful,

P.S, the preview doesn't show the attachment, so I am not certain it is there until I post.

DJinCA

Online orabanda

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #2 on: 03.02. 2021 06:24 »
Every head bolt requires a heavy duty high tensile washer under the head.
Often the head surface needs spot facing to restore flat surface for the washer.
no washer, "soft" standard washer, and / or dished surface will result in head bolts loosening (head gasket leaks).

Richard

Offline thackero

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #3 on: 03.02. 2021 14:23 »
When I do a search online it shows the 3 bolts are for the iron head. Are the alloy head 3 bolts the same part number ? Does anyone have another part number for suitable washers -9 off. Thanks

Online rocker21

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #4 on: 03.02. 2021 14:48 »
no the iron head bolts and the alloy head bolts are different, the alloy head ones are wasted in the middle, same thread and head size.
trying to post a pic which shows the bolts, not sure how to do this.
have a look at the draganfly website there is a pic which shows it.

Offline Klaus

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #5 on: 03.02. 2021 14:55 »
I'm just confused my partlist for the alloy heads  shows me two numbers
  A7, A10 Swing arm  67-283
A7 SS, A10 SR 67- 1114

I make my own washers 3mm thick.

cheers Klaus


If you think, everything is under control, you are not fast enought.

Offline DJinCA

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #6 on: 03.02. 2021 20:55 »
Ah! Interesting Klaus,

My parts book showed the 67-1114 being for the Shooting Star, no mention of an A10.

DJinCA

Offline DJinCA

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #7 on: 03.02. 2021 21:06 »
Sorry, clicked Post instead of Preview and accidentally posted early.  Looking at 67-1114 on the web shows short bolts (3/8-20) without waisting.  This includes sites perhaps more reliable that ebay.  Looking at Baxter's, the longer bolts are waisted, while the shorter ones are not.

DJinCA

Offline bikerboy

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #8 on: 08.02. 2021 23:37 »
https://draganfly.co.uk/product-category/bsa/sparesparts-for-bsa-a710-b3133-c101112-m202133/engine-gaskets-gearbox/cylinder-head-barrel/pre-unit-a-group-head/

This page is from draganfly (a BSA dealer in the UK) with all the necessary part numbers. SR/RR/RGS and A7SS all use the same bolts

They are useful because they have all the schematics for the A10

Online Greybeard

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #9 on: 09.02. 2021 12:02 »
Sorry, clicked Post instead of Preview and accidentally posted early...
I often need to go back and modify/edit a post

Offline RoyC

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Re: 1956 BSA A10 Road rocket Alloy Cylinder head
« Reply #10 on: 09.02. 2021 12:20 »
Sorry, clicked Post instead of Preview and accidentally posted early...
I often need to go back and modify/edit a post


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Must be something to do with getting old, haha.
My bike is a 1958 A7SS
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