Author Topic: A10 Frame Dimensions  (Read 1392 times)

Offline duncan32bsa

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A10 Frame Dimensions
« on: 06.07. 2010 19:42 »
Hi all,
I have now rendered my 1960 Golden Flash to largish lumps prior to rebuilding it...
I thought I'd check the frame dimensions, particularly as the front seat mount looked like it had been welded in place by someone on a work experience scheme.
I had assumed that the 1954 swinging arm frame drawings commonly available were consistent through the subsequent years, so imagine my surprise when I found that not only were they not consistent, they were several inches out.
e.g steering tube to tank mount approx 12" rather than 14.031". Tank mount to seat mount approx 10" compared to 8 13/32" and tank mount to top rear bracket about 26" rather than 23.781".
So, are they meant to be different and if so, do SA frame drawings for 1955 on exist anyway?
Of course, I could just ignore it and out it all back together but I'd rather know!
Thanks for any help offered.
Gary
1960 Golden Flash
1971 Norton Commando
2010 Triumph Tiger

Offline mark

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Re: A10 Frame Dimensions
« Reply #1 on: 07.07. 2010 03:15 »
Measuring along the top tube my 55 and 57 frames both have the same dimensions. Seat mount to tank mount is just over 10''
Regards
Mark
55 road rocket




71 Norton Commando Roadster 750


Australia

Offline duncan32bsa

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Re: A10 Frame Dimensions
« Reply #2 on: 07.07. 2010 13:02 »
Mark,
Thanks for that. It's a relief anyway. It does seem that the SA frame changed in '55 - or the frame drawings posted everywhere are wrong...
Gary
1960 Golden Flash
1971 Norton Commando
2010 Triumph Tiger

Offline dpaddock

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Re: A10 Frame Dimensions
« Reply #3 on: 08.07. 2010 04:55 »
Gary -
The first swing arm frames were introduced in 1954 and carried over to 1955, and are stamped CA7. The swing arm pivot was a solid shaft.
In 1956, the frame was changed to EA7 and incorporated a hollow pivot shaft plus other changes to adapt the Ariel-type brakes. Then came the FA7 and GA7 frames in 1958 and 1960, respectively.
That there is no dimensional similarity between the 1954 and 1960 frames is not surprising.

David
David
'57 Spitfire