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Technical (Descriptive Topic Titles - Stay on Topic) => Frame => Topic started by: laneplodder on 15.01. 2019 13:22

Title: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 15.01. 2019 13:22
Adm edit: Split from introduction board

Hey Guys, ha that's a pretty amazing guess from such a basic pic! Yes I believe it is the super rocket 650 head (67-1127) I think was the part no. last time I looked..The valves & bits I believe are also SR, with collet location on the very end of the stem..

Incidentally, even though the timing is a little early, we're eventually looking to obtain an A7 SS alloy head, if we come across one for reasonable money..Think the part no. on that is 67-1122. One was sold from Denmark this weekend gone for £180 complete with springs, guides etc (unfortunately I was beaten to the computer!)..

Yes family projects like these may not come up so often, although buying one ready done is great and wonderful, once finished, our bike may also have been worth the while (hopefully!!)

In reply to duTch, funnily enough my first round of questions were based on where the pedal mount (frame location) is meant to be. This pedal mount end had been cut off in the past for some reason, I tacked on a bush to the pedal end, to sit proud of the frame and these were the 'staged' pics for DVLA to get the logbook through..

Any thoughts are always welcome on what the bolt hole in this pic is used for though! (Hole under swing arm 'retaining' bolt)

Cheers folks,

Matt
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: chaterlea25 on 15.01. 2019 20:30
Hi Matt,
From your first photo it looks as though the brake pedal was mounted there
Or was that the staged photo?
All kinds of baffling things can appear on restoration projects  *eek*

John
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 15.01. 2019 21:05
Hi John,

Yes that was the staged pic, but seems to look a correct position for it. The swing arm pin is a snug/ good fit, (fitting the half width hub setup). The frame would need slightly boring out if I'd decide on swapping it for a hollow pin (which clearly that hasn't been done before). This brings me to question whether or not it could have had a b31/ m20 setup with the following fulcrum pin threaded into the frame?? Maybe as an odd adaptation?!

https://www.draganfly.co.uk/index.php/accessories-a-misc/product/13755-

Who knows!!

Thanks,

Matt
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: chaterlea25 on 15.01. 2019 21:38
Hi Matt,
Another possibility is that the frame is a factory replacement ?
Those had features that suited different year models

John
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 16.01. 2019 10:13
Hi John,

Hmm quite possibly..Was that a 'usual' sort of thing to have a replacement frame made? The frame has a bracket welded on the offside pillion hanger, which sort of dates it to having (maybe originally) Ariel alloy hubs with crossover style spindle. But the swing arm spindle (currently solid with half width brakes) currently fits very snug in the frame holes!

Maybe it's never had Ariel hubs or was given the option to be adapted?..hmm

Thanks,

Matt
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: RichardL on 16.01. 2019 12:33
Quote from: chaterlea25

Another possibility is that the frame is a factory replacement ?
Those had features that suited different year models.

But, you would think such a frame would accommodate a hollow spindle AND have a boss for a left-side, rod-pull brake. I've been of the belief (perhaps incorrectly) that frames for the first '56 models had both because of existing '55 stock with bosses.


But the swing arm spindle (currently solid with half width brakes) currently fits very snug in the frame holes!


This is very surprising because it would mean there was no standard way (whether left-side rod or right-side cable) for brakes to work. Maybe, somehow, the spindle is solid and oversized.  *doubt* *conf2* *pull hair out* *dunno*

Richard L.
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 16.01. 2019 15:08
Hi Richard, yes it would seem so, quite interesting like you say not to have left or right (straightforward) setup for either brake system - unless this mounting hole is used for that, with a pedal (still not yet known). The spindle does seem a good fit off the bike into the swing arm though..hmm

According to the VMCC library records, it came out as a Gold-flash in '57, whether that changes anything or not for what was available at the time?!

Guess there's always a good pair of boots to cater for the lack of back brake?!!  *smile*

Matt
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: JulianS on 16.01. 2019 15:26
Probably not one of the multi model factory replacement frames.

The photos are both from such an A series frame, showing all three different brake arrangements.

The third photo is a  poor copy of the 1960 parts service bulletin which introduced these frames.

When such a frame was supplied for the rod brake half width hub model it came with a suitable swinging arm, presumably to take the larger diameter spindle needed to fit the generic main frame.
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: JulianS on 16.01. 2019 16:47
Maybe I have missed it, but has the spindle hole in frame been measured?

The hollow spindle is 13/16 inch diameter and the solid spindle 5/8 inch diameter.
Title: Re: 1957 A7 (long awaited) project: Frame..
Post by: RayC10 on 16.01. 2019 17:15
1957...I would expect Arial hubs
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 16.01. 2019 17:49
Hi Guys,

Your second pic Julian is pretty interesting with the cable mounts both together - that's a new one on me! Ours is the cable mount shown on your pic at the top, the 'box type'.

Yes the swingarm hole is 5/8 size, having had a closer look, it seems to have a very thin bronze looking bush, maybe to reduce the size put in from factory? To give both options if one decided to switch brakes and bore it out?

Does seem abit strange for the year like you say Ray, the year indicates Ariel hubs, but odd things may have occurred in the factory?!

Thanks,

Matt
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: JulianS on 16.01. 2019 18:32
Had the factory done it hen they would have also included some means of mounting the brake pedal.

In 1957 they were producing Gold Star and A10 Spitfire frames with the rod brake so would not have needed to interupt their busy production line to make an (incomplete) one off.

Had it been experimental then the despatch information from the VMCC library would no doubt have indicated that it had been sent to developement or competition department. It probably tells you that it went to a dealer.
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: KiwiGF on 16.01. 2019 19:54
Hi Guys,

Your second pic Julian is pretty interesting with the cable mounts both together - that's a new one on me! Ours is the cable mount shown on your pic at the top, the 'box type'.

Yes the swingarm hole is 5/8 size, having had a closer look, it seems to have a very thin bronze looking bush, maybe to reduce the size put in from factory? To give both options if one decided to switch brakes and bore it out?

Does seem abit strange for the year like you say Ray, the year indicates Ariel hubs, but odd things may have occurred in the factory?!

Thanks,

Matt

Frame may have been modified to have a smaller swing arm hole? The holes can become oval requiring a “fix” and the brass Bush is evidence of that sort of fix, but that may not be the whole story. I’d clean off all the paint and have a look for non std welds etc

My 56 GF has “extra” holes in the frame indicating there were “transitional” frames at the start of the Ariel hubbed bikes.

Edit see this thread for more info on above https://www.a7a10.net/forum/index.php?topic=11650.0
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: laneplodder on 17.01. 2019 21:11
Hi guys,

Thanks for your thoughts.. It could well be that the spindle holes may have been reduced over the time, especially looking at the bronze looking bushes..

Yes I agree the frame isn't a one off - it does say Kings Norton, Stretford where it was originally dispatched to). Just a shame it isn't as straight forward as the rod type setup with all available LH fixings!

I'll keep looking for bits of unusual welding/ available holes!..

Thanks
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: RichardL on 18.01. 2019 00:04
Sooooo, getting back to Swarfy's concern for modifying an original frame by adding a boss for the left-side rod pull (a la pre-1956), maybe the mods to the swingarm spindle holes have set that ship assail. If you should opt for the boss mod, you'd need a pedal like this and the associated spindle (commonly available).

https://mikesclassiccyclespares.com/product/42-7003u/

Richard L. ("L" stands for "One-Track Mind." Or does it?)
Title: Re: 1957 A7 (long awaited) project: Frame.
Post by: KiwiGF on 18.01. 2019 00:18
Hi guys,

Thanks for your thoughts.. It could well be that the spindle holes may have been reduced over the time, especially looking at the bronze looking bushes..

Yes I agree the frame isn't a one off - it does say Kings Norton, Stretford where it was originally dispatched to). Just a shame it isn't as straight forward as the rod type setup with all available LH fixings!

I'll keep looking for bits of unusual welding/ available holes!..

Thanks

The non std welding I meant you to look for is around the swing arm spindle holes. A PO may have welded a steel Bush in that hole, as well as pressed in a thin brass Bush. That may have been to “convert” the frame to take a non Ariel hub swing arm, or due to the hole having worn oval, or both!

The close up pic of the thin brass Bush MIGHT also be showing the edge of a steel Bush, it’s not clear there is one tho, and might be my imagination.

When building my 56 basket case Ariel hubbed bike I had to address the issue of oval holes in the frame, to bore them out and weld in a Bush (in the right alignment) was an expensive proposition that in the end I got around.

The extra hole you have in 5he bracket may even have been to bolt a guide to the frame when boring it?